/* ===== 基础变量 ===== */
:root {
  --bg-primary: #f5f7fa;
  --bg-secondary: #ffffff;
  --bg-sidebar: #f0f2f5;
  --bg-hover: #e8ecf1;
  --text-primary: #1a1a2e;
  --text-secondary: #4a4a6a;
  --text-muted: #8888a0;
  --border-color: #d0d4dc;
  --accent-color: #2563eb;
  --accent-hover: #1d4ed8;
  --success: #16a34a;
  --danger: #dc2626;
  --warning: #d97706;
  --radius: 10px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  height: 100vh;
  overflow: hidden;
  font-size: 14px;
  line-height: 1.5;
}

/* ===== 通用 ===== */
.hidden { display: none !important; }

button {
  cursor: pointer;
  border: none;
  background: none;
  font-size: 14px;
}

input, textarea {
  font-family: inherit;
  font-size: 14px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 10px 12px;
  outline: none;
  width: 100%;
  transition: border-color 0.2s;
}

input:focus, textarea:focus {
  border-color: var(--accent-color);
}

textarea { resize: none; }

.btn-primary {
  background: var(--accent-color);
  color: white;
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 500;
}

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

.btn-text {
  color: var(--text-muted);
  padding: 6px 10px;
}

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

.btn-icon {
  font-size: 18px;
  padding: 6px;
  border-radius: 6px;
}

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

.btn-cancel {
  background: var(--bg-hover);
  color: var(--text-secondary);
  padding: 10px 20px;
  border-radius: 8px;
}

/* ===== 登录页 ===== */
.login-page {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.login-box {
  background: var(--bg-secondary);
  padding: 40px;
  border-radius: var(--radius);
  box-shadow: 0 10px 40px rgba(0,0,0,0.15);
  width: 360px;
  text-align: center;
}

.login-box h1 { font-size: 28px; margin-bottom: 4px; }

.login-box p { color: var(--text-muted); margin-bottom: 24px; }

.login-box input {
  margin-bottom: 12px;
  display: block;
}

.login-box button[type="submit"] {
  width: 100%;
  background: var(--accent-color);
  color: white;
  padding: 12px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 500;
  margin-top: 8px;
}

.login-hint {
  margin-top: 16px;
  color: var(--text-muted);
  font-size: 12px;
}

/* ===== PC 布局 ===== */
.pc-layout {
  display: flex;
  height: 100vh;
}

.sidebar {
  width: 280px;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 16px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 8px;
}

.sidebar-header h2 {
  font-size: 18px;
  flex: 1;
}

.session-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}

.session-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
  margin-bottom: 2px;
}

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

.session-item.active { background: #dbeafe; }

.session-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  background: var(--bg-secondary);
  flex-shrink: 0;
}

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

.session-name {
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.session-preview {
  font-size: 12px;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.session-meta {
  text-align: right;
  flex-shrink: 0;
}

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

.unread-badge {
  display: inline-block;
  background: var(--danger);
  color: white;
  font-size: 11px;
  padding: 1px 6px;
  border-radius: 10px;
  margin-top: 2px;
}

.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--text-muted);
}

/* 聊天区 */
.chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
}

.chat-header {
  padding: 14px 20px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-title { font-weight: 600; font-size: 16px; }

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

.message-list {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.message-bubble {
  max-width: 70%;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.message-bubble.user { align-self: flex-end; }

.message-bubble.bot { align-self: flex-start; }

.message-header-row {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--text-muted);
}

.message-bubble.user .message-header-row { justify-content: flex-end; }

.message-content {
  padding: 10px 14px;
  border-radius: 12px;
  word-break: break-word;
}

.message-bubble.user .message-content {
  background: var(--accent-color);
  color: white;
  border-bottom-right-radius: 4px;
}

.message-bubble.bot .message-content {
  background: var(--bg-sidebar);
  border-bottom-left-radius: 4px;
}

/* Thinking Block */
.thinking-block {
  background: #f0f0f0;
  border-radius: 8px;
  margin: 8px 0;
  font-size: 13px;
  overflow: hidden;
}

.thinking-toggle {
  padding: 8px 12px;
  cursor: pointer;
  color: #666;
  display: flex;
  align-items: center;
  gap: 6px;
  user-select: none;
}

.thinking-toggle:hover { background: #e8e8e8; }

.thinking-toggle .toggle-icon {
  transition: transform 0.2s;
  font-size: 10px;
}

.thinking-toggle.expanded .toggle-icon { transform: rotate(90deg); }

.thinking-content {
  padding: 0 12px 12px;
  display: none;
}

.thinking-content.expanded { display: block; }

.thinking-step {
  padding: 8px 0;
  border-top: 1px solid #e0e0e0;
}

.step-label {
  font-weight: 600;
  color: #333;
  margin-bottom: 4px;
  font-size: 12px;
}

.step-label.thinking { color: #2563eb; }

.step-label.tool { color: #d97706; }

.tool-call {
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 6px;
  padding: 10px;
  font-family: monospace;
  font-size: 12px;
}

.tool-name {
  color: #0066cc;
  font-weight: 600;
  margin-bottom: 6px;
}

.tool-io { display: flex; flex-direction: column; gap: 4px; }

.tool-io label { color: #666; font-size: 11px; }

.tool-io pre {
  background: #f8f8f8;
  padding: 6px;
  border-radius: 4px;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-all;
}

.tool-duration {
  text-align: right;
  color: #888;
  font-size: 11px;
}

/* 输入区 */
.input-area {
  padding: 12px 20px;
  border-top: 1px solid var(--border-color);
  background: var(--bg-secondary);
}

.input-box {
  display: flex;
  gap: 10px;
  align-items: flex-end;
}

.input-box textarea {
  flex: 1;
  max-height: 120px;
  min-height: 40px;
}

.input-box button {
  padding: 10px 24px;
  background: var(--accent-color);
  color: white;
  border-radius: 8px;
  font-weight: 500;
  white-space: nowrap;
}

.input-box button:hover { background: var(--accent-hover); }

/* ===== 手机端布局 ===== */
.mobile-layout {
  display: none;
  flex-direction: column;
  height: 100vh;
}

.mobile-header {
  padding: 14px 16px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  font-weight: 600;
  font-size: 16px;
  text-align: center;
}

.mobile-tab {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}

.bottom-nav {
  display: flex;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 6px 0;
  padding-bottom: env(safe-area-inset-bottom, 6px);
}

.nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 4px;
  color: var(--text-muted);
  transition: color 0.2s;
}

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

.nav-icon { font-size: 22px; }

.nav-label { font-size: 11px; }

/* 手机聊天页 */
.mobile-chat {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: var(--bg-secondary);
  display: flex;
  flex-direction: column;
  z-index: 100;
}

.mobile-chat-header {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 12px;
}

.mobile-chat-header button {
  font-size: 16px;
  color: var(--accent-color);
}

/* 用户中心 */
.profile-content {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.profile-card {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
}

.profile-card h3 {
  margin-bottom: 12px;
  font-size: 15px;
}

.profile-card input {
  margin-bottom: 10px;
}

.profile-card button {
  width: 100%;
  background: var(--accent-color);
  color: white;
  padding: 10px;
  border-radius: 8px;
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.stat-item {
  text-align: center;
  padding: 16px;
  background: var(--bg-primary);
  border-radius: 8px;
}

.stat-value {
  font-size: 24px;
  font-weight: 600;
  color: var(--accent-color);
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* 管理页 */
.manage-content {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.manage-section h3 {
  margin-bottom: 10px;
  font-size: 15px;
}

.manage-section .btn-primary {
  width: 100%;
  margin-bottom: 12px;
}

.bot-list, .group-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.manage-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px;
  background: var(--bg-secondary);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

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

.manage-item-name { font-weight: 500; }

.manage-item-meta {
  font-size: 12px;
  color: var(--text-muted);
}

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

.manage-item .btn-secondary {
  background: var(--bg-hover);
  color: var(--text-secondary);
  padding: 6px 10px;
  font-size: 13px;
  border-radius: 6px;
}

.manage-item .btn-danger {
  color: var(--danger);
  padding: 6px 12px;
  font-size: 13px;
}

.form-hint {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: -8px;
  margin-bottom: 8px;
}

/* 模态框 */
.modal {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: 20px;
}

.modal-content {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 24px;
  width: 100%;
  max-width: 420px;
  max-height: 90vh;
  overflow-y: auto;
}

.modal-content h3 { margin-bottom: 16px; }

.modal-content input,
.modal-content textarea {
  margin-bottom: 12px;
}

.modal-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  margin-top: 8px;
}

/* Bot 选择 */
.bot-select { margin: 12px 0; }

.bot-select p { margin-bottom: 8px; color: var(--text-secondary); }

.bot-checkbox {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px;
  border-radius: 6px;
  cursor: pointer;
}

.bot-checkbox:hover { background: var(--bg-hover); }

.bot-checkbox input { width: auto; }

/* 空状态 */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.empty-state-icon { font-size: 48px; margin-bottom: 12px; }

/* 响应式 */
@media (max-width: 768px) {
  .pc-layout { display: none; }
  .mobile-layout { display: flex; }
  body { font-size: 15px; }
}

@media (min-width: 769px) {
  .pc-layout { display: flex; }
  .mobile-layout { display: none; }
}

/* 滚动条 */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #c0c4cc; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #a0a4ac; }