:root {
  /* Светлая тема (Telegram Light) */
  --bg-color: #ffffff;
  --bg-secondary: #f0f2f5;
  --bg-tertiary: #e7eaee;
  --text-color: #0a0a0a;
  --text-secondary: #5f6165;
  --text-tertiary: #8e9196;
  --accent: #3390ec;
  --accent-light: #e3f2ff;
  --border: #e9ecef;
  --border-dark: #d3d7db;
  --message-out: #effdde;
  --message-in: #ffffff;
  --shadow: 0 2px 5px rgba(0,0,0,0.05);
  --hover: #f4f6f9;
  --danger: #e53e3e;
  --success: #00c853;
  --warning: #ffa000;
  --header-bg: #ffffff;
  --input-bg: #f4f6f9;
  --avatar-bg: #3390ec;
  --online: #00c853;
}

[data-theme="dark"] {
  /* Тёмная тема (Telegram Dark) */
  --bg-color: #1f1f1f;
  --bg-secondary: #2b2b2b;
  --bg-tertiary: #333333;
  --text-color: #ffffff;
  --text-secondary: #b0b3b8;
  --text-tertiary: #7a7f85;
  --accent: #71b6ff;
  --accent-light: #2b3b4c;
  --border: #3a3a3a;
  --border-dark: #4a4a4a;
  --message-out: #2b5278;
  --message-in: #2b2b2b;
  --shadow: 0 2px 5px rgba(0,0,0,0.2);
  --hover: #3a3a3a;
  --danger: #ff6b6b;
  --success: #69c0ff;
  --warning: #ffd666;
  --header-bg: #1f1f1f;
  --input-bg: #2b2b2b;
  --avatar-bg: #71b6ff;
  --online: #71b6ff;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
  background: var(--bg-secondary);
  color: var(--text-color);
  line-height: 1.4;
  transition: background 0.2s, color 0.2s;
}

/* ===== АВТОРИЗАЦИЯ ===== */
.auth-screen {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: var(--bg-secondary);
}

.auth-container {
  width: 100%;
  max-width: 400px;
  padding: 32px;
  background: var(--bg-color);
  border-radius: 16px;
  box-shadow: var(--shadow);
}

.auth-header {
  text-align: center;
  margin-bottom: 32px;
}

.auth-logo {
  font-size: 48px;
  margin-bottom: 16px;
}

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

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

/* ===== ЧАТ LAYOUT ===== */
.chat-layout {
  display: flex;
  height: 100vh;
  width: 100%;
  background: var(--bg-color);
}

/* Сайдбар */
.sidebar {
  width: 320px;
  background: var(--bg-color);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: relative;
}

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

.user-card {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  padding: 8px;
  border-radius: 12px;
  transition: background 0.2s;
  flex: 1;
}

.user-card:hover {
  background: var(--hover);
}

.avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--avatar-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 600;
  font-size: 20px;
  flex-shrink: 0;
  position: relative;
}

.avatar.small {
  width: 40px;
  height: 40px;
  font-size: 16px;
}

.avatar img {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
}

.online-indicator {
  position: absolute;
  bottom: 2px;
  right: 2px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--online);
  border: 2px solid var(--bg-color);
}

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

.user-name {
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.user-status {
  font-size: 12px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Кнопки действий */
.actions {
  display: flex;
  gap: 8px;
}

.icon-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 20px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

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

/* Поиск */
.search-section {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
}

.search-input {
  width: 100%;
  padding: 10px 16px;
  background: var(--input-bg);
  border: none;
  border-radius: 24px;
  font-size: 15px;
  color: var(--text-color);
  transition: all 0.2s;
}

.search-input:focus {
  outline: none;
  background: var(--bg-color);
  box-shadow: 0 0 0 2px var(--accent-light);
}

.search-input::placeholder {
  color: var(--text-tertiary);
}

/* Табы чатов */
.chat-tabs {
  display: flex;
  padding: 12px 16px;
  gap: 8px;
  border-bottom: 1px solid var(--border);
}

.tab {
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.tab:hover {
  background: var(--hover);
}

.tab.active {
  background: var(--accent);
  color: white;
}

/* Список чатов */
.chats-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}

.chat-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  border-radius: 12px;
  cursor: pointer;
  transition: background 0.2s;
  margin-bottom: 2px;
}

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

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

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

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

.chat-name {
  font-weight: 600;
  color: var(--text-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-time {
  font-size: 11px;
  color: var(--text-tertiary);
}

.chat-last-message {
  font-size: 13px;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: flex;
  align-items: center;
  gap: 4px;
}

.unread-badge {
  background: var(--accent);
  color: white;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  min-width: 20px;
  text-align: center;
}

.group-badge {
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 10px;
  margin-left: 8px;
}

/* Основная область чата */
.chat-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
}

.chat-header {
  padding: 12px 20px;
  background: var(--bg-color);
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-header-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.chat-header-title h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 2px;
}

.chat-header-status {
  font-size: 13px;
  color: var(--text-secondary);
}

/* Область сообщений */
.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  background: var(--bg-secondary);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.message-wrapper {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  max-width: 80%;
  animation: fadeIn 0.2s;
}

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

.message-bubble {
  background: var(--message-in);
  padding: 10px 14px;
  border-radius: 18px;
  box-shadow: var(--shadow);
  position: relative;
  word-wrap: break-word;
}

.message-wrapper.out .message-bubble {
  background: var(--message-out);
}

.message-sender {
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 4px;
}

.message-text {
  font-size: 15px;
  line-height: 1.45;
  color: var(--text-color);
  margin-bottom: 4px;
}

.message-meta {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 4px;
  font-size: 11px;
  color: var(--text-tertiary);
}

.message-image {
  max-width: 300px;
  max-height: 400px;
  border-radius: 12px;
  cursor: pointer;
  transition: opacity 0.2s;
}

.message-image:hover {
  opacity: 0.9;
}

/* Файловый вложения */
.file-attachment {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px;
  background: rgba(0,0,0,0.05);
  border-radius: 12px;
  min-width: 200px;
}

[data-theme="dark"] .file-attachment {
  background: rgba(255,255,255,0.05);
}

.file-icon {
  font-size: 24px;
}

.file-info {
  flex: 1;
}

.file-name {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 2px;
  word-break: break-word;
  color: var(--text-color);
}

.file-size {
  font-size: 11px;
  color: var(--text-tertiary);
}

.file-download {
  color: var(--accent);
  text-decoration: none;
  font-size: 20px;
  padding: 4px;
}

/* Разделитель дат */
.date-divider {
  text-align: center;
  margin: 16px 0;
  position: relative;
}

.date-divider span {
  background: var(--bg-tertiary);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 12px;
  color: var(--text-secondary);
}

/* Панель ввода */
.message-input-area {
  padding: 16px 20px;
  background: var(--bg-color);
  border-top: 1px solid var(--border);
  display: flex;
  gap: 12px;
  align-items: flex-end;
}

.message-input {
  flex: 1;
  padding: 12px 16px;
  background: var(--input-bg);
  border: none;
  border-radius: 24px;
  font-size: 15px;
  color: var(--text-color);
  resize: none;
  font-family: inherit;
  max-height: 120px;
  transition: all 0.2s;
}

.message-input:focus {
  outline: none;
  background: var(--bg-color);
  box-shadow: 0 0 0 2px var(--accent-light);
}

/* Модальные окна */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0,0,0,0.5);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  padding: 16px;
}

.modal-content {
  background: var(--bg-color);
  border-radius: 16px;
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

.modal-header {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-header h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-color);
}

.modal-close {
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--text-tertiary);
  padding: 4px;
}

.modal-body {
  padding: 24px;
}

.modal-footer {
  padding: 20px 24px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

/* Формы */
.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  color: var(--text-color);
  font-size: 14px;
  font-weight: 500;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  font-size: 15px;
  color: var(--text-color);
  transition: all 0.2s;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent);
  background: var(--bg-color);
}

/* Кнопки */
.btn {
  padding: 12px 24px;
  border: none;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

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

.btn-primary:hover {
  background: var(--accent);
  opacity: 0.9;
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-color);
}

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

/* Поиск пользователей */
.users-list {
  max-height: 400px;
  overflow-y: auto;
}

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

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

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

.user-item-name {
  font-weight: 500;
  color: var(--text-color);
  margin-bottom: 2px;
}

.user-item-email {
  font-size: 12px;
  color: var(--text-tertiary);
}

.user-item-action {
  background: var(--accent);
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 13px;
  cursor: pointer;
}

/* Участники группы */
.members-list {
  max-height: 300px;
  overflow-y: auto;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 8px;
}

.member-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px;
  border-radius: 8px;
}

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

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

/* Пустые состояния */
.empty-state {
  text-align: center;
  padding: 48px 24px;
  color: var(--text-secondary);
}

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

.empty-state h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 14px;
  margin-bottom: 24px;
}

/* Адаптивность */
@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: 100%;
    z-index: 100;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
  }
  
  .sidebar.active {
    transform: translateX(0);
  }
  
  .chat-main {
    width: 100%;
  }
  
  .message-wrapper {
    max-width: 90%;
  }
  
  .auth-container {
    margin: 16px;
  }
}

/* Анимации */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Скроллбар в стиле Telegram */
::-webkit-scrollbar {
  width: 6px;
}

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

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

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