/* ===== CSS Variables ===== */
:root {
  --primary: #07C160;
  --primary-dark: #06AD56;
  --primary-light: #95EC69;
  
  --bg-main: #EDEDED;
  --bg-white: #FFFFFF;
  --bg-input: #F7F7F7;
  --bg-hover: #F0F0F0;
  
  --text-primary: #191919;
  --text-secondary: #666666;
  --text-muted: #999999;
  --text-white: #FFFFFF;
  
  --border: #E6E6E6;
  --divider: #F0F0F0;
  
  --bubble-self: #95EC69;
  --bubble-other: #FFFFFF;
  
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.15);
  
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  
  --nav-height: 56px;
}

/* ===== Dark Theme ===== */
.dark-mode {
  --bg-main: #111111;
  --bg-white: #1E1E1E;
  --bg-input: #2A2A2A;
  --bg-hover: #333333;
  
  --text-primary: #E9E9E9;
  --text-secondary: #A0A0A0;
  --text-muted: #666666;
  
  --border: #333333;
  --divider: #2A2A2A;
  
  --bubble-self: #2B5A34;
  --bubble-other: #2A2A2A;
}

/* ===== Reset Styles ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  height: 100%;
  overflow: hidden;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Noto Sans SC', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.5;
}

/* ===== Page Container ===== */
.page {
  display: none;
  height: 100%;
  width: 100%;
}

.page.active {
  display: flex;
}

/* ===== Login Page ===== */
#loginPage {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  justify-content: center;
  align-items: center;
  padding: 20px;
  position: relative;
}

/* Login Language Switch */
.login-lang-switch {
  position: absolute;
  top: 20px;
  right: 20px;
  display: flex;
  gap: 8px;
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  padding: 4px;
  border-radius: 20px;
  z-index: 10;
}

.login-lang-switch .lang-option {
  padding: 6px 16px;
  border: none;
  background: transparent;
  color: white;
  font-size: 14px;
  font-weight: 500;
  border-radius: 16px;
  cursor: pointer;
  transition: all 0.3s;
  min-width: 50px;
}

.login-lang-switch .lang-option:hover {
  background: rgba(255, 255, 255, 0.3);
}

.login-lang-switch .lang-option.active {
  background: white;
  color: var(--primary);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.login-container {
  background: var(--bg-white);
  border-radius: var(--radius-xl);
  padding: 40px 32px;
  width: 100%;
  max-width: 400px;
  box-shadow: var(--shadow-lg);
  animation: slideUp 0.5s ease;
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.login-logo {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--primary), #4ECDC4);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  box-shadow: 0 8px 25px rgba(7, 193, 96, 0.3);
}

.login-logo i {
  font-size: 36px;
  color: white;
}

.login-title {
  text-align: center;
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.login-subtitle {
  text-align: center;
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.login-form, .register-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.avatar-upload {
  position: relative;
  width: 90px;
  height: 90px;
  margin: 0 auto 12px;
}

.avatar-preview {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  border: 3px solid var(--border);
}

.avatar-preview i {
  font-size: 36px;
  color: var(--text-muted);
}

.avatar-preview img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.avatar-upload-btn {
  position: absolute;
  bottom: 0;
  right: 0;
  width: 30px;
  height: 30px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s;
}

.avatar-upload-btn:hover {
  transform: scale(1.1);
}

.avatar-upload-btn i {
  font-size: 14px;
  color: white;
}

.input-group {
  display: flex;
  align-items: center;
  background: var(--bg-input);
  border-radius: var(--radius-lg);
  padding: 0 16px;
  height: 48px;
  border: 2px solid transparent;
  transition: all 0.2s;
}

.input-group:focus-within {
  border-color: var(--primary);
  background: var(--bg-white);
}

.input-group i {
  font-size: 18px;
  color: var(--text-muted);
  margin-right: 12px;
}

.input-group input {
  flex: 1;
  border: none;
  background: transparent;
  font-size: 15px;
  color: var(--text-primary);
  outline: none;
}

.input-group input::placeholder {
  color: var(--text-muted);
}

.login-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), #4ECDC4);
  border: none;
  border-radius: var(--radius-lg);
  color: white;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  margin-top: 8px;
}

.login-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(7, 193, 96, 0.3);
}

.login-btn:active {
  transform: translateY(0);
}

.register-btn {
  background: linear-gradient(135deg, #667eea, #764ba2);
}

.register-btn:hover {
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.form-switch {
  text-align: center;
  font-size: 14px;
  color: var(--text-secondary);
  margin-top: 8px;
}

.form-switch a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
}

.form-switch a:hover {
  text-decoration: underline;
}

.server-info {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--divider);
  font-size: 13px;
  color: var(--text-secondary);
}

.server-info strong {
  color: var(--primary);
}

/* ===== Main App Layout ===== */
#mainApp {
  display: none;
  flex-direction: column;
  height: 100%;
  background: var(--bg-main);
}

#mainApp.active {
  display: flex;
}

/* ===== Bottom Navigation ===== */
.main-nav {
  display: flex;
  align-items: center;
  justify-content: space-around;
  height: var(--nav-height);
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  padding: 0 10px;
  order: 2;
  flex-shrink: 0;
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 6px 16px;
  cursor: pointer;
  position: relative;
  transition: color 0.2s;
  color: var(--text-secondary);
}

.nav-item.active {
  color: var(--primary);
}

.nav-item i {
  font-size: 22px;
  margin-bottom: 2px;
}

.nav-item span {
  font-size: 11px;
}

.nav-item .badge {
  position: absolute;
  top: 2px;
  right: 8px;
  min-width: 16px;
  height: 16px;
  background: #FF4757;
  border-radius: 8px;
  font-size: 10px;
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 4px;
}

.nav-item .badge:empty {
  display: none;
}

/* ===== Main Content Area ===== */
.main-content {
  flex: 1;
  overflow: hidden;
  order: 1;
}

.tab-content {
  display: none;
  height: 100%;
  flex-direction: column;
  overflow: hidden;
}

.tab-content.active {
  display: flex;
}

/* ===== Tab Header ===== */
.tab-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.tab-header h1 {
  font-size: 20px;
  font-weight: 600;
}

.header-actions {
  display: flex;
  gap: 8px;
}

.icon-btn {
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-primary);
  transition: background 0.2s;
}

.icon-btn:hover {
  background: var(--bg-hover);
}

.icon-btn i {
  font-size: 18px;
}

/* ===== Search Bar ===== */
.search-bar {
  display: none;
  align-items: center;
  padding: 10px 16px;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  gap: 12px;
}

.search-bar.active {
  display: flex;
}

.search-bar i {
  color: var(--text-muted);
}

.search-bar input {
  flex: 1;
  border: none;
  background: var(--bg-input);
  padding: 10px 12px;
  border-radius: var(--radius-md);
  font-size: 14px;
  outline: none;
}

.search-cancel {
  background: none;
  border: none;
  color: var(--primary);
  font-size: 14px;
  cursor: pointer;
}

/* ===== Chat List ===== */
.chat-list {
  flex: 1;
  overflow-y: auto;
  background: var(--bg-white);
}

.chat-item {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  cursor: pointer;
  transition: background 0.2s;
  border-bottom: 1px solid var(--divider);
}

.chat-item:hover {
  background: var(--bg-hover);
}

.chat-avatar {
  width: 50px;
  height: 50px;
  border-radius: 8px;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 12px;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
}

.chat-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.chat-avatar i {
  font-size: 24px;
  color: var(--text-muted);
}

.status-dot {
  position: absolute;
  bottom: 2px;
  right: 2px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid var(--bg-white);
}

.status-dot.online {
  background: var(--primary);
}

.status-dot.offline {
  background: var(--text-muted);
}

.chat-info {
  flex: 1;
  min-width: 0;
}

.chat-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}

.chat-info h3 {
  font-size: 16px;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-time {
  font-size: 12px;
  color: var(--text-muted);
  flex-shrink: 0;
  margin-left: 8px;
}

.chat-preview {
  font-size: 13px;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ===== Empty State ===== */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.empty-state i {
  font-size: 64px;
  margin-bottom: 16px;
  opacity: 0.5;
}

.empty-state p {
  font-size: 16px;
  margin-bottom: 8px;
}

.empty-state span {
  font-size: 13px;
}

/* ===== Contacts List ===== */
.contact-actions {
  display: flex;
  flex-direction: column;
  background: var(--bg-white);
  border-bottom: 8px solid var(--bg-main);
}

.contact-action-item {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  cursor: pointer;
  transition: background 0.2s;
  border-bottom: 1px solid var(--divider);
}

.contact-action-item:hover {
  background: var(--bg-hover);
}

.contact-action-item:last-child {
  border-bottom: none;
}

.action-icon {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 12px;
}

.action-icon i {
  font-size: 18px;
  color: white;
}

.action-icon.green {
  background: var(--primary);
}

.action-icon.blue {
  background: #3498DB;
}

.contact-action-item span {
  flex: 1;
  font-size: 15px;
}

.contact-action-item .count {
  color: var(--text-muted);
  font-size: 14px;
}

.contact-list {
  flex: 1;
  overflow-y: auto;
  background: var(--bg-white);
}

.contact-item {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  cursor: pointer;
  transition: background 0.2s;
  border-bottom: 1px solid var(--divider);
}

.contact-item:hover {
  background: var(--bg-hover);
}

.contact-avatar {
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 12px;
  position: relative;
  overflow: hidden;
}

.contact-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.contact-avatar i {
  font-size: 20px;
  color: var(--text-muted);
}

.contact-info h3 {
  font-size: 15px;
  font-weight: 500;
  margin-bottom: 2px;
}

.contact-info p {
  font-size: 12px;
  color: var(--text-muted);
}

.online-count {
  padding: 12px 16px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  background: var(--bg-white);
  border-top: 1px solid var(--border);
}

/* ===== Discover Page ===== */
.discover-list {
  background: var(--bg-white);
}

.discover-item {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  cursor: pointer;
  transition: background 0.2s;
  border-bottom: 1px solid var(--divider);
}

.discover-item:hover {
  background: var(--bg-hover);
}

.discover-icon {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 12px;
}

.discover-icon i {
  font-size: 18px;
  color: white;
}

.discover-title {
  flex: 1;
  font-size: 15px;
}

.discover-item > i:last-child {
  color: var(--text-muted);
  font-size: 14px;
}

/* ===== Profile Page ===== */
.profile-card {
  display: flex;
  align-items: center;
  padding: 20px 16px;
  background: var(--bg-white);
  margin-bottom: 8px;
  cursor: pointer;
}

.profile-avatar {
  width: 64px;
  height: 64px;
  border-radius: 10px;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 14px;
  overflow: hidden;
}

.profile-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.profile-avatar i {
  font-size: 28px;
  color: var(--text-muted);
}

.profile-info {
  flex: 1;
}

.profile-info h2 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}

.profile-info p {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.user-id {
  font-size: 12px;
  color: var(--text-muted);
}

.profile-qr {
  font-size: 20px;
  color: var(--text-muted);
}

.profile-menu {
  background: var(--bg-white);
  margin-bottom: 8px;
}

.menu-item {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  cursor: pointer;
  transition: background 0.2s;
  border-bottom: 1px solid var(--divider);
}

.menu-item:last-child {
  border-bottom: none;
}

.menu-item:hover {
  background: var(--bg-hover);
}

.menu-item > i:first-child {
  font-size: 18px;
  width: 24px;
  color: var(--primary);
  margin-right: 12px;
}

.menu-item span {
  flex: 1;
  font-size: 15px;
}

.menu-item > i:last-child {
  color: var(--text-muted);
  font-size: 14px;
}

.theme-toggle {
  position: relative;
}

.theme-toggle input {
  display: none;
}

.theme-toggle label {
  display: block;
  width: 48px;
  height: 26px;
  background: var(--border);
  border-radius: 13px;
  cursor: pointer;
  position: relative;
  transition: background 0.3s;
}

.theme-toggle label::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 22px;
  height: 22px;
  background: white;
  border-radius: 50%;
  transition: transform 0.3s;
  box-shadow: var(--shadow-sm);
}

.theme-toggle input:checked + label {
  background: var(--primary);
}

.theme-toggle input:checked + label::after {
  transform: translateX(22px);
}

/* Language Toggle */
.language-toggle {
  display: flex;
  gap: 4px;
  background: var(--bg-input);
  padding: 2px;
  border-radius: 6px;
}

.lang-option {
  padding: 4px 12px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 13px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
}

.lang-option:hover {
  background: var(--bg-hover);
}

.lang-option.active {
  background: var(--primary);
  color: white;
}

.server-info-card {
  background: var(--bg-white);
  padding: 16px;
  margin: 8px 16px;
  border-radius: var(--radius-lg);
}

.server-info-card h3 {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.server-info-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.server-info-card strong {
  color: var(--primary);
}

/* ===== Chat Window ===== */
.chat-window {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-main);
  display: none;
  flex-direction: column;
  z-index: 100;
}

.chat-window.active {
  display: flex;
}

/* Empty chat state */
.chat-empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  padding: 40px 20px;
  text-align: center;
}

.chat-empty-state i {
  font-size: 64px;
  color: var(--text-secondary);
  margin-bottom: 20px;
  opacity: 0.3;
}

.chat-empty-state h3 {
  font-size: 18px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.chat-empty-state p {
  font-size: 14px;
  color: var(--text-muted);
}

.chat-header {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.back-btn {
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-primary);
  margin-right: 8px;
}

.back-btn:hover {
  background: var(--bg-hover);
}

.chat-info {
  flex: 1;
  min-width: 0;
}

.chat-info h2 {
  font-size: 17px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-status {
  font-size: 12px;
  color: var(--text-muted);
}

.chat-status.online {
  color: var(--primary);
}

.chat-actions {
  display: flex;
  gap: 4px;
}

/* ===== Message Area ===== */
.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
}

.messages-list {
  display: flex;
  flex-direction: column;
  gap: 16px; /* Beta 0.1.0: Increased message gap for cleaner UI */
  padding-bottom: 8px;
}

.messages-empty {
  text-align: center;
  color: var(--text-muted);
  padding: 40px;
}

.message {
  display: flex;
  align-items: flex-start;
  max-width: 80%;
}

.message.mine {
  align-self: flex-end;
  flex-direction: row-reverse;
}

.message.other {
  align-self: flex-start;
}

.message-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  flex-shrink: 0;
}

.message.mine .message-avatar {
  margin-left: 8px;
}

.message.other .message-avatar {
  margin-right: 8px;
}

.message-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.message-avatar i {
  font-size: 16px;
  color: var(--text-muted);
}

.message-content {
  background: var(--bubble-other);
  padding: 10px 14px;
  border-radius: 18px;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.message.mine .message-content {
  background: var(--bubble-self);
  border-bottom-right-radius: 4px;
}

.message.other .message-content {
  border-bottom-left-radius: 4px;
}

.message-sender {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 4px;
  display: block;
}

.message-text {
  font-size: 15px;
  line-height: 1.5;
  word-break: break-word;
}

.message-time {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 4px;
  display: block;
  text-align: right;
}

.message.mine .message-time {
  color: rgba(0, 0, 0, 0.5);
}

.message-image {
  max-width: 200px;
  max-height: 200px;
  border-radius: 8px;
  cursor: pointer;
}

.message-video {
  max-width: 250px;
  border-radius: 8px;
}

.message-file {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  background: var(--bg-input);
  border-radius: 8px;
  text-decoration: none;
  color: var(--text-primary);
}

.message-file i {
  font-size: 24px;
  color: var(--primary);
}

.message-voice {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  background: var(--bg-input);
  border-radius: 20px;
  cursor: pointer;
  min-width: 80px;
}

.message-voice i {
  font-size: 14px;
  color: var(--primary);
}

.message-reply {
  font-size: 12px;
  padding: 6px 10px;
  background: rgba(0, 0, 0, 0.05);
  border-radius: 6px;
  margin-bottom: 6px;
  border-left: 3px solid var(--primary);
}

.message-reply span {
  color: var(--primary);
  font-weight: 500;
}

.message-reply p {
  color: var(--text-secondary);
  margin-top: 2px;
}

/* ===== Input Area ===== */
.input-area {
  display: flex;
  align-items: flex-end;
  padding: 10px 12px;
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  gap: 8px;
  flex-shrink: 0;
}

.input-tools, .input-actions {
  display: flex;
  gap: 4px;
}

.tool-btn {
  width: 36px;
  height: 36px;
  border: none;
  background: transparent;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.tool-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.input-wrapper {
  flex: 1;
  min-width: 0;
}

.text-input {
  width: 100%;
  min-height: 36px;
  max-height: 120px; /* Beta 0.1.0: Increased max height */
  padding: 10px 16px; /* Beta 0.1.0: Increased padding */
  background: var(--bg-input);
  border-radius: 20px; /* Beta 0.1.0: Rounder borders */
  font-size: 15px;
  line-height: 1.5; /* Beta 0.1.0: Increased line height */
  outline: none;
  overflow-y: auto;
  word-break: break-word;
  transition: background 0.2s, box-shadow 0.2s; /* Beta 0.1.0: Added transition */
}

.text-input:focus {
  background: var(--bg-white);
  box-shadow: 0 0 0 2px var(--primary-light);
}

.text-input:empty::before {
  content: attr(placeholder);
  color: var(--text-muted);
}

.send-btn {
  width: 36px;
  height: 36px;
  border: none;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: white;
  transition: transform 0.2s;
}

.send-btn:hover {
  transform: scale(1.1);
}

.send-btn:active {
  transform: scale(0.95);
}

/* ===== Emoji Panel ===== */
.emoji-panel {
  display: none;
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  padding: 12px;
  max-height: 200px;
  overflow-y: auto;
}

.emoji-panel.active {
  display: block;
}

.emoji-grid {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 8px;
}

.emoji-item {
  font-size: 24px;
  padding: 6px;
  text-align: center;
  cursor: pointer;
  border-radius: 8px;
  transition: background 0.2s;
}

.emoji-item:hover {
  background: var(--bg-hover);
}

/* ===== Attachment Panel ===== */
.attach-panel {
  display: none;
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  padding: 16px;
  position: relative;
  z-index: 10;
}

.attach-panel.active {
  display: block;
}

.attach-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.attach-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
}

.attach-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 6px;
  transition: transform 0.2s;
}

.attach-item:hover .attach-icon {
  transform: scale(1.1);
}

.attach-icon i {
  font-size: 24px;
  color: white;
}

.attach-item span {
  font-size: 12px;
  color: var(--text-secondary);
}

/* ===== Reply Preview ===== */
.reply-preview {
  display: none;
  align-items: center;
  padding: 8px 12px;
  background: var(--bg-input);
  border-left: 3px solid var(--primary);
  margin: 0 12px 8px;
  border-radius: 0 8px 8px 0;
}

.reply-preview.active {
  display: flex;
}

.reply-content {
  flex: 1;
}

.reply-to {
  font-size: 12px;
  color: var(--primary);
}

.reply-content p {
  font-size: 13px;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.reply-cancel {
  width: 28px;
  height: 28px;
  border: none;
  background: transparent;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-muted);
}

/* ===== Typing Indicator ===== */
.typing-indicator {
  display: none;
  align-items: center;
  padding: 12px 16px;
  gap: 6px;
}

.typing-indicator.active {
  display: flex;
}

.typing-indicator span {
  width: 8px;
  height: 8px;
  background: var(--text-muted);
  border-radius: 50%;
  animation: typing 1.4s infinite ease-in-out both;
}

.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }

@keyframes typing {
  0%, 80%, 100% { transform: scale(0.6); opacity: 0.5; }
  40% { transform: scale(1); opacity: 1; }
}

.typing-indicator p {
  font-size: 12px;
  color: var(--text-muted);
  margin-left: 4px;
}

/* ===== Voice Recording ===== */
.voice-recording {
  display: none;
  flex-direction: column;
  align-items: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.8);
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  border-radius: 20px 20px 0 0;
}

.voice-recording.active {
  display: flex;
}

.voice-wave {
  display: flex;
  gap: 4px;
  height: 40px;
  align-items: center;
}

.wave-bar {
  width: 4px;
  background: var(--primary);
  border-radius: 2px;
  animation: wave 0.5s ease-in-out infinite alternate;
}

.wave-bar:nth-child(1) { animation-delay: 0s; height: 20px; }
.wave-bar:nth-child(2) { animation-delay: 0.1s; height: 30px; }
.wave-bar:nth-child(3) { animation-delay: 0.2s; height: 40px; }
.wave-bar:nth-child(4) { animation-delay: 0.1s; height: 30px; }
.wave-bar:nth-child(5) { animation-delay: 0s; height: 20px; }

@keyframes wave {
  to { height: 10px; }
}

.recording-time {
  color: white;
  font-size: 24px;
  font-weight: 600;
  margin: 12px 0;
}

.recording-hint {
  color: rgba(255, 255, 255, 0.6);
  font-size: 13px;
}

/* ===== Modals ===== */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 200;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--bg-white);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 400px;
  max-height: 80vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  animation: modalSlideUp 0.3s ease;
}

@keyframes modalSlideUp {
  from {
    opacity: 0;
    transform: translateY(50px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}

.modal-header h2 {
  font-size: 18px;
  font-weight: 600;
}

.modal-close {
  width: 32px;
  height: 32px;
  border: none;
  background: transparent;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-muted);
}

.modal-close:hover {
  background: var(--bg-hover);
}

.modal-body {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
}

.modal-body h3 {
  font-size: 14px;
  color: var(--text-secondary);
  margin: 16px 0 12px;
}

.member-select {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 200px;
  overflow-y: auto;
}

.member-item {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  background: var(--bg-input);
  border-radius: var(--radius-md);
  cursor: pointer;
  gap: 12px;
}

.member-item:hover {
  background: var(--bg-hover);
}

.member-checkbox {
  width: 20px;
  height: 20px;
  accent-color: var(--primary);
}

.member-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.member-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.member-avatar i {
  font-size: 16px;
  color: var(--text-muted);
}

.modal-footer {
  display: flex;
  gap: 12px;
  padding: 16px 20px;
  border-top: 1px solid var(--border);
}

.btn {
  flex: 1;
  height: 42px;
  border: none;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-secondary {
  background: var(--bg-input);
  color: var(--text-primary);
}

.btn-secondary:hover {
  background: var(--bg-hover);
}

.btn-primary {
  background: var(--primary);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
}

/* ===== Image Preview Modal ===== */
.image-preview-modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.95);
  z-index: 300;
  justify-content: center;
  align-items: center;
}

.image-preview-modal.active {
  display: flex;
}

.preview-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
  border: none;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  color: white;
  font-size: 20px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}

#previewImage {
  max-width: 90%;
  max-height: 80%;
  object-fit: contain;
  border-radius: 8px;
}

.preview-actions {
  position: absolute;
  bottom: 30px;
  display: flex;
  gap: 20px;
}

.preview-actions button {
  padding: 12px 24px;
  background: rgba(255, 255, 255, 0.1);
  border: none;
  border-radius: 24px;
  color: white;
  font-size: 14px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
}

.preview-actions button:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* ===== Context Menu ===== */
.context-menu {
  display: none;
  position: fixed;
  background: var(--bg-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 140px;
  z-index: 250;
  overflow: hidden;
}

.context-menu.active {
  display: block;
}

.context-menu .menu-item {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  cursor: pointer;
  gap: 10px;
  font-size: 14px;
  color: var(--text-primary);
  border-bottom: 1px solid var(--divider);
}

.context-menu .menu-item:last-child {
  border-bottom: none;
}

.context-menu .menu-item:hover {
  background: var(--bg-hover);
}

.context-menu .menu-item i {
  font-size: 14px;
  color: var(--text-secondary);
  width: 18px;
}

/* ===== Toast Notification ===== */
.toast {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: rgba(0, 0, 0, 0.8);
  color: white;
  padding: 12px 24px;
  border-radius: 24px;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  z-index: 400;
  opacity: 0;
  transition: all 0.3s ease;
  pointer-events: none;
}

.toast.active {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast.success { background: var(--primary); }
.toast.error { background: #E74C3C; }
.toast.warning { background: #F39C12; }
.toast.info { background: #3498DB; }

.toast-icon {
  font-size: 16px;
}

/* ===== Scrollbar Styles (Beta 0.1.0 Optimized) ===== */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Beta 0.1.0: Smooth scrolling optimization */
.chat-list,
.contact-list,
.messages-container,
.moments-list,
.modal-body {
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior: contain;
}

/* ===== Responsive Adaptation ===== */
@media (min-width: 768px) {
  #mainApp {
    flex-direction: row;
    gap: 0;
  }
  
  /* Beta 0.1.0: Lock navigation width */
  .main-nav {
    flex-direction: column;
    width: 70px;
    min-width: 70px;
    max-width: 70px;
    height: 100%;
    border-top: none;
    border-right: 1px solid var(--border);
    order: 0;
    padding: 20px 0;
    justify-content: flex-start;
    gap: 8px;
    flex-shrink: 0;
    flex-grow: 0;
  }
  
  .nav-item {
    padding: 12px;
  }
  
  .main-content {
    order: 1;
    width: 300px;
    min-width: 300px;
    max-width: 300px;
    border-right: 1px solid var(--border);
    flex-shrink: 0;
    height: 100%;
    overflow: hidden;
    flex-grow: 0;
  }
  
  .chat-window {
    position: relative;
    top: auto;
    left: auto;
    right: auto;
    bottom: auto;
    flex: 1;
    display: flex;
    flex-direction: column;
    z-index: 0;
    height: 100%;
    min-width: 300px;
    order: 2;
    border-right: 1px solid var(--border);
  }
  
  .chat-window {
    display: flex;
  }
  
  .chat-window:not(.active) .chat-header,
  .chat-window:not(.active) .messages-container,
  .chat-window:not(.active) .reply-preview,
  .chat-window:not(.active) .input-area {
    display: none;
  }
  
  .chat-window.active .chat-empty-state {
    display: none !important;
  }
  
  .back-btn {
    display: none;
  }
  
  /* Chat window inner layout */
  .chat-header {
    flex-shrink: 0;
  }
  
  .chat-messages {
    flex: 1;
    overflow-y: auto;
  }
  
  .chat-input {
    flex-shrink: 0;
  }
  
  /* Attachment panel centered on PC */
  .attach-panel {
    position: absolute;
    bottom: 70px;
    left: 50%;
    transform: translateX(-50%);
    width: 360px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
  }
  
  .emoji-panel {
    position: absolute;
    bottom: 70px;
    left: 50%;
    transform: translateX(-50%);
    width: 360px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
  }
}

@media (min-width: 1024px) {
  /* Beta 0.1.0: Lock content area width */
  .main-content {
    width: 340px;
    min-width: 340px;
    max-width: 340px;
    flex-grow: 0;
    flex-shrink: 0;
  }
  
  .login-container {
    padding: 50px 40px;
    max-width: 440px;
  }
}

/* ===== Role Titles and Badges ===== */
.role-badge {
  display: inline-block;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 600;
  margin-left: 6px;
  vertical-align: middle;
}

.role-badge.super-admin {
  background: linear-gradient(135deg, #FFD700, #FFA500);
  color: #8B4513;
  box-shadow: 0 1px 4px rgba(255, 165, 0, 0.4);
}

.role-badge.admin {
  background: linear-gradient(135deg, #FF6B6B, #EE5A5A);
  color: white;
}

.role-badge.moderator {
  background: linear-gradient(135deg, #4FACFE, #00F2FE);
  color: white;
}

.role-badge.vip {
  background: linear-gradient(135deg, #FFD700, #FFEC8B);
  color: #8B6914;
}

.friend-badge {
  display: inline-block;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 500;
  margin-left: 6px;
  background: var(--primary-light);
  color: var(--primary-dark);
}

/* ===== Contacts List Enhanced ===== */
.contact-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.contact-actions {
  display: flex;
  gap: 4px;
}

.add-friend-btn {
  padding: 6px 12px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 11px;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.add-friend-btn:hover {
  background: var(--primary-dark);
  transform: scale(1.05);
}

.add-friend-btn:disabled {
  background: var(--text-muted);
  cursor: not-allowed;
  transform: none;
}

/* ===== Friend Requests Panel ===== */
.friend-requests-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: 320px;
  height: 100%;
  background: var(--bg-white);
  box-shadow: var(--shadow-lg);
  z-index: 2001;
  transform: translateX(100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
}

.friend-requests-panel.active {
  transform: translateX(0);
}

.friend-requests-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.friend-requests-header h3 {
  font-size: 16px;
  font-weight: 600;
}

.close-requests-btn {
  background: none;
  border: none;
  font-size: 20px;
  cursor: pointer;
  color: var(--text-secondary);
}

.friend-requests-list {
  flex: 1;
  overflow-y: auto;
  padding: 12px;
}

.friend-request-item {
  display: flex;
  align-items: center;
  padding: 12px;
  background: var(--bg-input);
  border-radius: var(--radius-md);
  margin-bottom: 8px;
  gap: 12px;
}

.friend-request-item .avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  flex-shrink: 0;
}

.friend-request-item .avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.friend-request-item .avatar i {
  font-size: 20px;
  color: var(--primary);
}

.request-info {
  flex: 1;
  min-width: 0;
}

.request-info .name {
  font-weight: 600;
  font-size: 14px;
  margin-bottom: 2px;
}

.request-info .time {
  font-size: 12px;
  color: var(--text-muted);
}

.request-actions {
  display: flex;
  gap: 6px;
}

.accept-btn, .reject-btn {
  padding: 6px 12px;
  border: none;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.accept-btn {
  background: var(--primary);
  color: white;
}

.accept-btn:hover {
  background: var(--primary-dark);
}

.reject-btn {
  background: var(--bg-hover);
  color: var(--text-secondary);
}

.reject-btn:hover {
  background: #FF6B6B;
  color: white;
}

/* ===== Nav Friend Request Button ===== */
.friend-request-badge {
  position: absolute;
  top: 6px;
  right: 6px;
  min-width: 18px;
  height: 18px;
  background: #FF4757;
  color: white;
  border-radius: 9px;
  font-size: 11px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 4px;
}

/* ===== Message Header Role Mark ===== */
.message-header {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 4px;
}

.message-header.mine {
  justify-content: flex-end;
}

.message-header .message-sender {
  font-weight: 600;
  font-size: 13px;
  color: var(--text-secondary);
}

.message-header .role-badge {
  font-size: 10px;
  padding: 2px 6px;
}

.message .role-badge {
  color: var(--text-secondary);
}

.message .role-badge {
  margin-left: 4px;
}

/* ===== Group Chat Management Panel ===== */
.room-settings-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: 360px;
  height: 100%;
  background: var(--bg-white);
  box-shadow: var(--shadow-lg);
  z-index: 2000;
  transform: translateX(100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
}

.room-settings-panel.active {
  transform: translateX(0);
}

.room-settings-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.room-settings-content {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
}

.settings-section {
  margin-bottom: 20px;
}

.settings-section h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text-secondary);
}

.member-item {
  display: flex;
  align-items: center;
  padding: 10px;
  background: var(--bg-input);
  border-radius: var(--radius-sm);
  margin-bottom: 6px;
  gap: 10px;
}

.member-item .avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* Group avatar edit */
.room-avatar-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  padding: 10px;
  border-radius: var(--radius-md);
  transition: background 0.2s;
}

.room-avatar-wrapper:hover {
  background: var(--bg-hover);
}

.room-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  color: var(--primary);
  overflow: hidden;
}

.room-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.edit-hint {
  font-size: 12px;
  color: var(--primary);
}

.member-item .info {
  flex: 1;
}

.member-item .name {
  font-weight: 500;
  font-size: 14px;
}

.member-item .role-tag {
  font-size: 11px;
  color: var(--text-muted);
}

.kick-btn {
  padding: 4px 8px;
  background: #FF6B6B;
  color: white;
  border: none;
  border-radius: 4px;
  font-size: 11px;
  cursor: pointer;
  opacity: 0;
  transition: all 0.2s;
}

.member-item:hover .kick-btn {
  opacity: 1;
}

.kick-btn:hover {
  background: #EE5A5A;
}

/* ===== Mute/Ban Status Notification ===== */
.status-alert {
  padding: 12px 16px;
  background: #FFF3CD;
  color: #856404;
  border-radius: var(--radius-md);
  margin: 12px;
  font-size: 13px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.status-alert.banned {
  background: #F8D7DA;
  color: #721C24;
}

.status-alert.muted {
  background: #FFF3CD;
  color: #856404;
}

.status-alert i {
  font-size: 16px;
}

/* ===== Non-Friend Message Limit ===== */
.message-limit-notice {
  padding: 10px 16px;
  background: var(--bg-input);
  color: var(--text-secondary);
  font-size: 13px;
  text-align: center;
  border-top: 1px solid var(--border);
}

.message-limit-notice button {
  background: var(--primary);
  color: white;
  border: none;
  padding: 6px 12px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
  margin-left: 8px;
}

/* ===== Overlay ===== */
.panel-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 1999;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
  pointer-events: none;
}

.panel-overlay.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

/* ===== Notification Tips ===== */
.notification-toast {
  position: fixed;
  top: 20px;
  right: 20px;
  padding: 12px 20px;
  background: var(--bg-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  z-index: 2000;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideInRight 0.3s ease;
  max-width: 320px;
}

.notification-toast.success {
  border-left: 4px solid var(--primary);
}

.notification-toast.error {
  border-left: 4px solid #FF6B6B;
}

.notification-toast.warning {
  border-left: 4px solid #FFA500;
}

@keyframes slideInRight {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

/* ===== PC Optimization ===== */
@media (min-width: 768px) {
  /* Main app three-column layout */
  #mainApp {
    display: flex;
    flex-direction: row;
  }
  
  /* Sidebar fixed width */
  .main-nav {
    width: 80px;
    height: 100vh;
    flex-direction: column;
    justify-content: flex-start;
    padding-top: 20px;
    border-right: 1px solid var(--border);
    border-top: none;
  }
  
  .nav-item {
    padding: 16px 12px;
    margin-bottom: 8px;
  }
  
  .nav-item span {
    font-size: 12px;
  }
  
  /* Tab content area */
  .tab-content {
    width: 320px;
    min-width: 320px;
    height: 100vh;
    border-right: 1px solid var(--border);
  }
  
  .tab-content.active {
    display: flex;
    flex-direction: column;
  }
  
  /* Chat window takes remaining space */
  #chatWindow {
    flex: 1;
    width: auto;
    height: 100vh;
    position: relative;
    transform: none;
    display: flex !important;
    flex-direction: column;
  }
  
  #chatWindow.active {
    transform: none;
  }
  
  /* Back button hidden on PC */
  #backBtn {
    display: none;
  }
  
  /* Chat header */
  .chat-header {
    padding: 16px 24px;
  }
  
  /* Chat area */
  .chat-messages {
    padding: 16px 24px;
  }
  
  /* Message bubble larger click area */
  .message-bubble {
    padding: 12px 18px;
    font-size: 15px;
    max-width: 60%;
    cursor: default;
  }
  
  /* Input area */
  .chat-input {
    padding: 16px 24px;
  }
  
  .message-input {
    padding: 14px 18px;
    font-size: 15px;
    min-height: 48px;
  }
  
  /* Contact list item larger */
  .contact-item, .chat-item {
    padding: 14px 20px;
  }
  
  .contact-item:hover, .chat-item:hover {
    background: var(--bg-hover);
  }
  
  /* Selected state */
  .contact-item.selected, .chat-item.selected {
    background: var(--bg-hover);
    border-left: 3px solid var(--primary);
  }
  
  /* Avatar larger */
  .contact-item .avatar,
  .chat-item .avatar {
    width: 50px;
    height: 50px;
    font-size: 20px;
  }
  
  /* Attachment panel */
  .attach-panel {
    bottom: 80px;
    width: 400px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: var(--radius-lg);
  }
  
  .attach-item {
    padding: 16px 12px;
    cursor: pointer;
    transition: background 0.2s;
  }
  
  .attach-item:hover {
    background: var(--bg-hover);
    border-radius: var(--radius-md);
  }
  
  /* Friend requests panel wider */
  .friend-requests-panel,
  .room-settings-panel {
    width: 400px;
  }
  
  /* Modal larger */
  .modal-content {
    max-width: 500px;
    padding: 32px;
  }
  
  /* Action buttons */
  .icon-btn {
    width: 44px;
    height: 44px;
    font-size: 18px;
  }
  
  .icon-btn:hover {
    background: var(--bg-hover);
  }
  
  /* Send button */
  .send-btn {
    width: 50px;
    height: 50px;
    font-size: 18px;
  }
  
  /* Emoji panel */
  .emoji-panel {
    bottom: 80px;
    width: 400px;
    left: 50%;
    transform: translateX(-50%);
    max-height: 320px;
  }
  
  .emoji-grid {
    grid-template-columns: repeat(10, 1fr);
  }
  
  .emoji-item {
    font-size: 26px;
    padding: 10px;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    border-radius: var(--radius-sm);
  }
  
  .emoji-item:hover {
    transform: scale(1.2);
    background: var(--bg-hover);
  }
  
  /* Scrollbar beautify */
  ::-webkit-scrollbar {
    width: 8px;
    height: 8px;
  }
  
  ::-webkit-scrollbar-track {
    background: var(--bg-main);
  }
  
  ::-webkit-scrollbar-thumb {
    background: #CCC;
    border-radius: 4px;
  }
  
  ::-webkit-scrollbar-thumb:hover {
    background: #AAA;
  }
  
  .dark-mode ::-webkit-scrollbar-thumb {
    background: #444;
  }
  
  .dark-mode ::-webkit-scrollbar-thumb:hover {
    background: #555;
  }
  
  /* Empty chat prompt */
  .empty-chat-hint {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100%;
    color: var(--text-muted);
    font-size: 16px;
  }
}

/* ===== Large Screen Optimization (Beta 0.1.0 Fixed Sidebar Width Lock) ===== */
@media (min-width: 1200px) {
  /* Beta 0.1.0: Lock content area width */
  .main-content {
    width: 360px !important;
    min-width: 360px !important;
    max-width: 360px !important;
    flex-grow: 0 !important;
    flex-shrink: 0 !important;
  }
  
  /* Beta 0.1.0: Lock navigation width */
  .main-nav {
    width: 70px !important;
    min-width: 70px !important;
    max-width: 70px !important;
    flex-grow: 0 !important;
    flex-shrink: 0 !important;
  }
  
  .tab-content {
    width: 100%;
  }
  
  .message-bubble {
    max-width: 50%;
  }
  
  .attach-panel,
  .emoji-panel {
    width: 450px;
  }
}

/* ===== Mobile Adaptation ===== */
@media (max-width: 767px) {
  .friend-requests-panel,
  .room-settings-panel {
    width: 100%;
  }
  
  .contact-actions {
    opacity: 1;
  }
}

/* ===== Member Selection List ===== */
.member-select-list {
  max-height: 400px;
  overflow-y: auto;
}

.member-select-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  cursor: pointer;
  border-bottom: 1px solid var(--border);
  transition: background 0.2s;
}

.member-select-item:hover {
  background: var(--bg-hover);
}

.member-select-item input[type="checkbox"] {
  width: 20px;
  height: 20px;
  cursor: pointer;
}

.member-select-item .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: var(--text-muted);
  overflow: hidden;
}

.member-select-item .avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.member-select-item .name {
  flex: 1;
  font-size: 15px;
}

/* ===== Group Members List Optimization ===== */
.member-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.member-item:last-child {
  border-bottom: none;
}

.member-item .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: var(--text-muted);
  overflow: hidden;
}

.member-item .avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.member-item .info {
  flex: 1;
}

.member-item .info .name {
  font-size: 14px;
  font-weight: 500;
}

.member-item .info .role-tag {
  font-size: 12px;
  color: var(--text-muted);
}

.member-item .kick-btn {
  padding: 6px 12px;
  background: #FF6B6B;
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 12px;
  cursor: pointer;
  transition: background 0.2s;
}

.member-item .kick-btn:hover {
  background: #e74c3c;
}

/* ===== Group Chat Settings Panel ===== */
.room-settings-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: 320px;
  height: 100%;
  background: var(--bg-white);
  box-shadow: var(--shadow-lg);
  z-index: 1001;
  transform: translateX(100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
}

.room-settings-panel.active {
  transform: translateX(0);
}

.room-settings-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.room-settings-content {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
}

.settings-section {
  margin-bottom: 24px;
}

.settings-section h4 {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

#roomMembersList {
  max-height: 300px;
  overflow-y: auto;
}

/* ===== Game Center ===== */
.games-modal {
  max-width: 600px;
}

.games-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  padding: 8px;
}

.game-card {
  background: var(--bg-input);
  border-radius: var(--radius-lg);
  padding: 20px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s;
  border: 2px solid transparent;
}

.game-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.game-icon {
  width: 60px;
  height: 60px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 12px;
}

.game-icon i {
  font-size: 28px;
  color: white;
}

.game-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.game-card p {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Game invite friends list */
.invite-hint {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.invite-hint span {
  color: var(--primary);
  font-weight: 600;
}

.friend-list-for-game {
  max-height: 300px;
  overflow-y: auto;
}

.friend-item-game {
  display: flex;
  align-items: center;
  padding: 12px;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background 0.2s;
  gap: 12px;
}

.friend-item-game:hover {
  background: var(--bg-hover);
}

.friend-item-game .avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.friend-item-game .avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.friend-item-game .info {
  flex: 1;
}

.friend-item-game .info .name {
  font-size: 15px;
  font-weight: 500;
}

.friend-item-game .info .status {
  font-size: 12px;
  color: var(--text-muted);
}

.friend-item-game .info .status.online {
  color: var(--primary);
}

.friend-item-game .invite-btn {
  padding: 8px 16px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s;
}

.friend-item-game .invite-btn:hover {
  background: var(--primary-dark);
}

.friend-item-game .invite-btn:disabled {
  background: var(--text-muted);
  cursor: not-allowed;
}

/* Game panel */
.game-panel {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bg-main);
  z-index: 3000;
  display: none;
  flex-direction: column;
}

.game-panel.active {
  display: flex;
}

.game-header {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  gap: 12px;
}

.game-title {
  flex: 1;
  font-size: 18px;
  font-weight: 600;
}

.game-status {
  font-size: 13px;
  color: var(--text-secondary);
  padding: 4px 12px;
  background: var(--bg-input);
  border-radius: var(--radius-md);
}

.game-status.playing {
  color: var(--primary);
  background: rgba(7, 193, 96, 0.1);
}

.game-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
  overflow: auto;
  position: relative;
  z-index: 1;
}

.game-board {
  position: relative;
  z-index: 10;
  pointer-events: auto;
}

.board-cell {
  pointer-events: auto;
  cursor: pointer;
}

.game-controls {
  padding: 16px;
  background: var(--bg-white);
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: center;
  gap: 12px;
}

.game-controls button {
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.game-controls .primary-btn {
  background: var(--primary);
  color: white;
  border: none;
}

.game-controls .primary-btn:hover {
  background: var(--primary-dark);
}

.game-controls .secondary-btn {
  background: var(--bg-input);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.game-controls .secondary-btn:hover {
  background: var(--bg-hover);
}

/* Game invite prompt */
.game-invite-toast {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%) translateY(-150%);
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  z-index: 4000;
  transition: transform 0.3s ease;
  min-width: 320px;
}

.game-invite-toast.active {
  transform: translateX(-50%) translateY(0);
}

.invite-info {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
}

.invite-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.invite-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.invite-text .invite-from {
  font-weight: 600;
  font-size: 15px;
}

.invite-text .invite-game {
  font-size: 13px;
  color: var(--text-secondary);
}

.invite-text .invite-game span {
  color: var(--primary);
}

.invite-actions {
  display: flex;
  gap: 8px;
}

.invite-actions button {
  padding: 8px 16px;
  border-radius: var(--radius-md);
  font-size: 13px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
  border: none;
  transition: all 0.2s;
}

.accept-invite {
  background: var(--primary);
  color: white;
}

.accept-invite:hover {
  background: var(--primary-dark);
}

.decline-invite {
  background: var(--bg-input);
  color: var(--text-primary);
}

.decline-invite:hover {
  background: #FF6B6B;
  color: white;
}

/* Gomoku/Tic-tac-toe board */
.game-board {
  display: grid;
  gap: 1px;
  background: var(--border);
  border: 2px solid var(--text-primary);
  border-radius: 4px;
}

.game-board.gomoku {
  grid-template-columns: repeat(15, 30px);
  grid-template-rows: repeat(15, 30px);
}

.game-board.tictactoe {
  grid-template-columns: repeat(3, 80px);
  grid-template-rows: repeat(3, 80px);
}

.board-cell {
  background: #DEB887;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.2s;
}

.board-cell:hover {
  background: #D2B48C;
}

.board-cell.black::after {
  content: '';
  width: 80%;
  height: 80%;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, #444, #000);
  box-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.board-cell.white::after {
  content: '';
  width: 80%;
  height: 80%;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, #fff, #ddd);
  box-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.board-cell.x::after {
  content: '✕';
  font-size: 48px;
  font-weight: bold;
  color: #FF6B6B;
}

.board-cell.o::after {
  content: '○';
  font-size: 56px;
  font-weight: bold;
  color: var(--primary);
}

.board-cell.win {
  background: rgba(7, 193, 96, 0.3);
}

/* Game info */
.game-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  max-width: 500px;
  margin-bottom: 20px;
  padding: 12px 20px;
  background: var(--bg-white);
  border-radius: var(--radius-lg);
}

.player-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.player-info .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.player-info .avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.player-info .name {
  font-weight: 500;
}

.player-info .piece {
  width: 20px;
  height: 20px;
  border-radius: 50%;
}

.player-info .piece.black {
  background: radial-gradient(circle at 30% 30%, #444, #000);
}

.player-info .piece.white {
  background: radial-gradient(circle at 30% 30%, #fff, #ddd);
  border: 1px solid var(--border);
}

.player-info.active {
  padding: 8px 12px;
  background: rgba(7, 193, 96, 0.1);
  border-radius: var(--radius-md);
}

.turn-indicator {
  font-size: 14px;
  color: var(--text-secondary);
}

/* Guess number game */
.guess-game {
  text-align: center;
  width: 100%;
  max-width: 400px;
}

.guess-hint {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.guess-input-group {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
}

.guess-input {
  flex: 1;
  padding: 14px 18px;
  font-size: 18px;
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  text-align: center;
  outline: none;
  transition: border-color 0.2s;
}

.guess-input:focus {
  border-color: var(--primary);
}

.guess-btn {
  padding: 14px 24px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius-lg);
  font-size: 16px;
  font-weight: 500;
  cursor: pointer;
}

.guess-history {
  max-height: 200px;
  overflow-y: auto;
  text-align: left;
}

.guess-item {
  display: flex;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--bg-input);
  border-radius: var(--radius-md);
  margin-bottom: 8px;
}

.guess-number {
  font-weight: 600;
  font-size: 18px;
}

.guess-result {
  color: var(--text-secondary);
}

.guess-result.high {
  color: #FF6B6B;
}

.guess-result.low {
  color: #4ECDC4;
}

.guess-result.correct {
  color: var(--primary);
  font-weight: 600;
}

/* Rock paper scissors */
.rps-game {
  text-align: center;
}

.rps-choices {
  display: flex;
  gap: 20px;
  margin-bottom: 30px;
}

.rps-choice {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  background: var(--bg-white);
  border: 3px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 48px;
  cursor: pointer;
  transition: all 0.2s;
}

.rps-choice:hover {
  transform: scale(1.1);
  border-color: var(--primary);
}

.rps-choice.selected {
  border-color: var(--primary);
  background: rgba(7, 193, 96, 0.1);
}

.rps-choice.win {
  border-color: var(--primary);
  background: rgba(7, 193, 96, 0.2);
}

.rps-choice.lose {
  border-color: #FF6B6B;
  background: rgba(255, 107, 107, 0.2);
}

.rps-vs {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  margin-bottom: 20px;
}

.rps-player {
  text-align: center;
}

.rps-player .choice-display {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: var(--bg-input);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 60px;
  margin-bottom: 10px;
}

.rps-player .name {
  font-weight: 500;
}

.rps-score {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 20px;
}

.rps-result {
  font-size: 20px;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-lg);
}

.rps-result.win {
  background: rgba(7, 193, 96, 0.1);
  color: var(--primary);
}

.rps-result.lose {
  background: rgba(255, 107, 107, 0.1);
  color: #FF6B6B;
}

.rps-result.draw {
  background: var(--bg-input);
  color: var(--text-secondary);
}

/* PC game optimization */
@media (min-width: 768px) {
  .games-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  
  .game-board.gomoku {
    grid-template-columns: repeat(15, 36px);
    grid-template-rows: repeat(15, 36px);
  }
  
  .game-board.tictactoe {
    grid-template-columns: repeat(3, 100px);
    grid-template-rows: repeat(3, 100px);
  }
  
  .game-content {
    padding: 40px;
  }
  
  .game-info {
    max-width: 600px;
  }
  
  .rps-choice {
    width: 120px;
    height: 120px;
    font-size: 56px;
  }
  
  .rps-player .choice-display {
    width: 150px;
    height: 150px;
    font-size: 72px;
  }
}

/* ===== Message Context Menu ===== */
.context-menu {
  position: fixed;
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
  min-width: 180px;
  z-index: 10000;
  opacity: 0;
  visibility: hidden;
  transform: scale(0.95);
  transition: all 0.15s ease;
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.context-menu.active {
  opacity: 1;
  visibility: visible;
  transform: scale(1);
}

.context-menu-reactions {
  display: flex;
  padding: 12px;
  gap: 8px;
  justify-content: center;
  border-bottom: 1px solid var(--border-color);
  background: var(--bg-secondary);
}

.context-menu-reactions span {
  font-size: 24px;
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.context-menu-reactions span:hover {
  background: var(--bg-hover);
  transform: scale(1.2);
}

.context-menu-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  cursor: pointer;
  transition: background 0.15s ease;
  color: var(--text-primary);
}

.context-menu-item:hover {
  background: var(--bg-hover);
}

.context-menu-item .icon {
  font-size: 16px;
  width: 20px;
  text-align: center;
}

.context-menu-item.delete-item {
  color: #FF6B6B;
}

.context-menu-item.delete-item:hover {
  background: rgba(255, 107, 107, 0.1);
}

/* ===== Message Reaction Bubbles ===== */
.message-reactions {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-top: 6px;
}

.reaction-bubble {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  background: var(--bg-secondary);
  border-radius: 12px;
  font-size: 14px;
  cursor: pointer;
  transition: all 0.15s ease;
  border: 1px solid var(--border-color);
}

.reaction-bubble:hover {
  background: var(--bg-hover);
  transform: scale(1.05);
}

.reaction-bubble.active {
  background: rgba(7, 193, 96, 0.15);
  border-color: var(--primary);
}

.reaction-bubble .count {
  font-size: 12px;
  color: var(--text-secondary);
}

/* ===== Poke Animation ===== */
.poke-animation {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 10001;
  font-size: 80px;
  animation: pokeShake 0.6s ease-in-out;
  pointer-events: none;
}

@keyframes pokeShake {
  0%, 100% { transform: translate(-50%, -50%) rotate(0deg); }
  10%, 30%, 50%, 70%, 90% { transform: translate(-50%, -50%) rotate(-5deg); }
  20%, 40%, 60%, 80% { transform: translate(-50%, -50%) rotate(5deg); }
}

.poke-toast {
  position: fixed;
  top: 20%;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, #FF6B6B, #FF8E53);
  color: white;
  padding: 16px 32px;
  border-radius: var(--radius-lg);
  font-size: 18px;
  font-weight: 600;
  box-shadow: 0 8px 32px rgba(255, 107, 107, 0.4);
  z-index: 10002;
  animation: pokeToastIn 0.3s ease, pokeToastOut 0.3s ease 2.7s forwards;
}

@keyframes pokeToastIn {
  from {
    opacity: 0;
    transform: translateX(-50%) translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
  }
}

@keyframes pokeToastOut {
  from {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
  }
  to {
    opacity: 0;
    transform: translateX(-50%) translateY(-20px);
  }
}

/* Beta 0.1.0: Fade-in animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========================================
   1.0.0 - Enhanced Features
   ======================================== */

/* Connection Status Indicator */
.connection-status {
  position: fixed;
  top: 10px;
  right: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  font-size: 12px;
  z-index: 10000;
  transition: all 0.3s ease;
}

.connection-status .status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.connection-status.connected .status-dot {
  background: var(--primary);
}

.connection-status.connecting .status-dot {
  background: #FFA500;
}

.connection-status.disconnected .status-dot {
  background: #FF4444;
}

.connection-status.connected {
  opacity: 0.7;
}

.connection-status.connecting,
.connection-status.disconnected {
  opacity: 1;
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* Unread Badge */
.unread-badge {
  position: absolute;
  top: 8px;
  right: 8px;
  min-width: 18px;
  height: 18px;
  padding: 0 6px;
  background: #FF4444;
  color: white;
  border-radius: 9px;
  font-size: 11px;
  font-weight: 600;
  display: none;
  align-items: center;
  justify-content: center;
  line-height: 1;
  box-shadow: 0 2px 4px rgba(255, 68, 68, 0.3);
  z-index: 10;
}

.contact-item,
.room-item {
  position: relative;
}

/* Message Preview Truncation */
.contact-message,
.room-message {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 200px;
}

/* Rate Limit Warning */
.rate-limit-warning {
  background: #FFF3CD;
  color: #856404;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  margin: 8px 0;
  font-size: 13px;
  text-align: center;
  animation: fadeInUp 0.3s ease;
}

/* Enhanced Toast Styles */
.toast.rate-limit {
  background: linear-gradient(135deg, #FFA500, #FF8C00);
}

/* Notification Permission Banner */
.notification-banner {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  box-shadow: var(--shadow-sm);
}

.notification-banner button {
  background: white;
  color: var(--primary);
  border: none;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s;
}

.notification-banner button:hover {
  transform: scale(1.05);
}

/* Message Queue Indicator */
.message-queue-indicator {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.8);
  color: white;
  padding: 8px 16px;
  border-radius: var(--radius-lg);
  font-size: 12px;
  z-index: 10001;
  display: none;
  align-items: center;
  gap: 8px;
}

.message-queue-indicator.active {
  display: flex;
  animation: fadeInUp 0.3s ease;
}

/* Version Info */
.version-info {
  position: fixed;
  bottom: 10px;
  left: 10px;
  font-size: 11px;
  color: var(--text-muted);
  z-index: 9999;
  opacity: 0.5;
  transition: opacity 0.3s;
}

.version-info:hover {
  opacity: 1;
}

/* ========================================
   Beta 0.1.0 - UI/UX Optimization Notes
   ========================================
   1. Locked sidebar width (nav 70px, content 300-360px)
   2. Enhanced scrollbar with smooth scrolling
   3. Improved input box interaction
   4. Message spacing optimization
   ======================================== */
/* Language Switch Button */
.lang-switch-btn {
  position: relative;
  font-size: 14px !important;
  font-weight: 600;
  transition: all 0.3s ease;
}

.lang-switch-btn .lang-text {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.lang-switch-btn:hover {
  background: rgba(0, 0, 0, 0.08);
  transform: scale(1.05);
}

.lang-switch-btn:active {
  transform: scale(0.95);
}

/* Language transition animation */
[data-i18n], [data-i18n-placeholder], [data-i18n-title] {
  transition: opacity 0.2s ease;
}

.lang-switching [data-i18n],
.lang-switching [data-i18n-placeholder],
.lang-switching [data-i18n-title] {
  opacity: 0.6;
}

/* Login Page Language Switch */
.login-lang-btn {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(0, 0, 0, 0.1);
  border-radius: 20px;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  font-size: 14px;
  font-weight: 600;
}

.login-lang-btn:hover {
  background: rgba(255, 255, 255, 1);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.login-lang-btn i {
  font-size: 16px;
  color: #07c160;
}

.login-lang-btn .lang-text {
  color: #333;
}