/* ============================================================
   Morph / 另我 — 设计系统
   融合 Apple HIG（弹簧缓动、平滑连续性）
   与 Google MD（Ripple 反馈、物理阴影层级）
   ============================================================ */

/* === CSS 变量：设计令牌 === */
:root {
  /* 品牌色系 */
  --brand: #1677FF;
  --brand-hover: #0958D9;
  --brand-active: #003EB3;
  --brand-light: rgba(22, 119, 255, 0.08);
  --brand-glow: rgba(22, 119, 255, 0.15);

  /* 背景色 */
  --nav-bg: #2B2B2B;
  --list-bg: #F7F8FA;
  --chat-bg: #F5F5F6;
  --white: #FFFFFF;

  /* 边框 */
  --border-light: #EBEDF0;
  --border-input: #E5E6E8;

  /* 文字 */
  --text-primary: #1F1F1F;
  --text-secondary: #6E6E6E;
  --text-placeholder: #bbb;

  /* 阴影系统（MD 层级） */
  --shadow-rest: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-lift: 0 4px 12px rgba(0, 0, 0, 0.12);
  --shadow-press: 0 1px 2px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.16);
  --shadow-blue: 0 2px 8px rgba(22, 119, 255, 0.3);
  --shadow-blue-lift: 0 4px 16px rgba(22, 119, 255, 0.4);

  /* 圆角体系 */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-pill: 9999px;
  --radius-bubble-ai: 4px 12px 12px 12px;
  --radius-bubble-user: 12px 4px 12px 12px;

  /* 缓动函数：Apple 弹簧 + MD 标准 */
  --ease-standard: cubic-bezier(0.25, 0.1, 0.25, 1);
  --ease-md: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-bounce: cubic-bezier(0.25, 0.8, 0.25, 1.2);

  /* 时长 */
  --dur-fast: 150ms;
  --dur-normal: 250ms;
  --dur-spring: 400ms;
  --dur-ripple: 500ms;
}

/* === Reset & Base === */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  background: var(--white);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow: hidden;
}

/* 全局过渡（主题切换用） */
body,
.app,
.sidebar-left,
.chat-list,
.chat-main,
.chat-top,
.chat-messages,
.chat-input-area,
.search-box,
.conversation,
.bubble.echo,
.panel,
.modal {
  transition: background-color 0.3s var(--ease-md),
              color 0.3s var(--ease-md),
              border-color 0.3s var(--ease-md),
              box-shadow 0.3s var(--ease-md);
}

/* === 三栏布局 === */
.app {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ================================================================
   1. 左侧导航栏
   ================================================================ */
.sidebar-left {
  width: 60px;
  background: var(--nav-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px 0 16px;
  gap: 6px;
  flex-shrink: 0;
  z-index: 2;
  box-shadow: 1px 0 10px rgba(0, 0, 0, 0.2);
}

/* -- 用户头像 -- */
.user-avatar {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  background: linear-gradient(145deg, #4096FF, var(--brand));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  flex-shrink: 0;
  position: relative;
  transition: transform var(--dur-spring) var(--ease-spring),
    box-shadow var(--dur-spring) var(--ease-spring);
  box-shadow: 0 2px 10px rgba(22, 119, 255, 0.4);
}

.user-avatar::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: calc(var(--radius-md) + 4px);
  border: 2px solid rgba(22, 119, 255, 0.18);
  opacity: 0;
  transform: scale(1.1);
  transition: opacity var(--dur-spring) var(--ease-spring),
              transform var(--dur-spring) var(--ease-spring);
  pointer-events: none;
}

.user-avatar:hover {
  transform: scale(1.12);
  box-shadow: 0 6px 20px rgba(22, 119, 255, 0.55);
}

.user-avatar:hover::after {
  opacity: 1;
  transform: scale(1);
}

.user-avatar:active {
  transform: scale(0.94);
  box-shadow: var(--shadow-press);
  transition: all 100ms var(--ease-standard);
}

/* -- 导入记忆按钮推到底部 -- */
.sidebar-left #navMemoryBtn {
  margin-top: auto;
}

.nav-btn {
  width: 42px;
  height: 42px;
  border: none;
  background: transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 20px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  position: relative;
  overflow: hidden;
  transition: all var(--dur-normal) var(--ease-standard);
}

.nav-btn:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--brand);
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.25);
}

.nav-btn:active {
  transform: scale(0.9);
  background: rgba(255, 255, 255, 0.14);
  transition: all 100ms var(--ease-standard);
}

/* ================================================================
   2. 中间会话列表
   ================================================================ */
.chat-list {
  width: 260px;
  background: var(--list-bg);
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border-light);
  flex-shrink: 0;
  z-index: 1;
  overflow-y: auto;
}

/* -- 搜索框 -- */
.search-box {
  margin: 16px;
  padding: 10px 14px;
  background: var(--white);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.05);
  transition: all var(--dur-spring) var(--ease-spring);
}

.search-box:hover,
.search-box:focus-within {
  border-color: var(--brand);
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.06),
    0 0 0 2px var(--brand-glow);
}

.search-icon {
  font-size: 14px;
  flex-shrink: 0;
}

.search-box input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  font-size: 13px;
  color: var(--text-primary);
}

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

/* -- 会话项 -- */
.conversation {
  display: flex;
  align-items: center;
  padding: 12px 16px;
  gap: 12px;
  position: relative;
  margin: 0 8px 2px;
  border-radius: var(--radius-md);
  transition: all var(--dur-normal) var(--ease-standard);
}

.conversation::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 10px;
  bottom: 10px;
  width: 0;
  background: var(--brand);
  border-radius: 0 3px 3px 0;
  transition: width var(--dur-spring) var(--ease-spring);
}

.conversation:hover {
  background: #ebedf0;
  transform: translateY(-1px);
  box-shadow: var(--shadow-lift);
}

.conversation:active {
  transform: scale(0.98);
  box-shadow: var(--shadow-press);
  transition: all 100ms var(--ease-standard);
}

.conversation.active {
  background: var(--brand-light);
  box-shadow: none;
  transform: none;
}

.conversation.active::before {
  width: 3px;
}

.conversation.active .conv-preview {
  color: var(--brand-active);
}

.conv-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: linear-gradient(135deg, #A8D8FF 0%, #1677FF 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 16px;
  font-weight: 700;
  flex-shrink: 0;
  box-shadow: 0 2px 6px rgba(22, 119, 255, 0.22);
}

.conversation:nth-child(3) .conv-avatar {
  background: linear-gradient(135deg, #52c41a 0%, #95de64 100%);
}

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

.conv-name {
  font-weight: 600;
  font-size: 14px;
  color: var(--text-primary);
  margin-bottom: 3px;
}

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

/* ================================================================
   3. 右侧聊天主区域
   ================================================================ */
.chat-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--white);
  min-width: 0;
}

.chat-top {
  padding: 12px 24px;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--white);
  flex-shrink: 0;
  z-index: 3;
}

.chat-status {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chat-name {
  font-weight: 650;
  font-size: 17px;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--brand);
  display: inline-block;
  flex-shrink: 0;
  animation: statusBreathe 3s ease-in-out infinite;
}

@keyframes statusBreathe {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.35; transform: scale(0.75); }
}

.status-text {
  font-size: 11px;
  color: var(--text-secondary);
}

/* -- 聊天设置按钮 + 下拉容器 -- */
.chat-top-right {
  position: relative;
}

.chat-settings {
  width: 32px;
  height: 32px;
  border: none;
  background: transparent;
  border-radius: 50%;
  cursor: pointer;
  font-size: 16px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all var(--dur-normal) var(--ease-standard);
}

.chat-settings:hover {
  color: var(--brand);
  background: var(--brand-glow);
}

/* -- 下拉菜单 -- */
.dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 220px;
  background: var(--white);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(-8px);
  pointer-events: none;
  transition: opacity 0.2s var(--ease-md), transform 0.2s var(--ease-md);
  z-index: 10;
  overflow: hidden;
}

.dropdown-menu.show {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.dropdown-item {
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-size: 13px;
  color: var(--text-primary);
  transition: background var(--dur-fast) var(--ease-standard);
}

.dropdown-item:hover {
  background: var(--brand-light);
}

.dropdown-arrow {
  font-size: 12px;
  color: var(--text-secondary);
}

.dropdown-divider {
  height: 1px;
  background: var(--border-light);
  margin: 4px 0;
}

/* -- AI 设置子面板 -- */
.ai-settings-panel {
  padding: 8px 16px 14px;
  display: none;
  border-bottom: 1px solid var(--border-light);
}

.ai-settings-panel.show {
  display: block;
}

.ai-setting-row {
  margin-bottom: 12px;
}

.ai-setting-row:last-child {
  margin-bottom: 0;
}

.ai-setting-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.ai-setting-value {
  font-weight: 600;
  color: var(--brand);
}

/* 滑块 */
.slider {
  -webkit-appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: var(--border-light);
  outline: none;
}

.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--brand);
  cursor: pointer;
  box-shadow: 0 1px 4px rgba(22, 119, 255, 0.3);
  transition: box-shadow var(--dur-fast) var(--ease-standard);
}

.slider::-webkit-slider-thumb:hover {
  box-shadow: 0 2px 8px rgba(22, 119, 255, 0.45);
}

/* 单选组 */
.radio-group {
  display: flex;
  gap: 8px;
}

.radio-label {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 6px 8px;
  border: 1px solid var(--border-input);
  border-radius: var(--radius-sm);
  font-size: 12px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--dur-fast) var(--ease-standard);
}

.radio-label:hover {
  border-color: var(--brand);
}

.radio-label:has(input:checked) {
  border-color: var(--brand);
  background: var(--brand-light);
  color: var(--brand);
}

.radio-label input {
  display: none;
}

/* -- 消息区域 -- */
.chat-messages {
  flex: 1;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: var(--chat-bg);
  position: relative;
  isolation: isolate;
}

.chat-messages::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background: radial-gradient(ellipse at 30% 30%, rgba(22, 119, 255, 0.03) 0%, transparent 55%);
  animation: auraBreathe 6s ease-in-out infinite;
}

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

/* ---- 聊天气泡 ---- */
.message {
  display: flex;
  flex-direction: column;
  max-width: 100%;
  animation: messageSlideIn var(--dur-spring) var(--ease-spring) both;
  position: relative;
  z-index: 1;
}

@keyframes messageSlideIn {
  from { transform: translateY(6px); opacity: 0; }
  to   { transform: translateY(0);    opacity: 1; }
}

.message.echo  { align-items: flex-start; }
.message.user  { align-items: flex-end; }

.bubble {
  max-width: 72%;
  padding: 12px 16px;
  font-size: 14px;
  line-height: 1.65;
  word-break: break-word;
  position: relative;
  transition: box-shadow var(--dur-normal) var(--ease-standard),
    transform var(--dur-normal) var(--ease-standard);
}

.bubble.echo {
  background: linear-gradient(135deg, #F5F5F6 0%, #EDEDEF 100%);
  color: #333;
  border-radius: var(--radius-bubble-ai);
  box-shadow: var(--shadow-rest);
}

.bubble.echo:hover {
  background: #E8E8EA;
  box-shadow: var(--shadow-lift);
}

.bubble.echo::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: var(--brand-light);
  border-radius: 1px;
  pointer-events: none;
}

.bubble.user {
  background: linear-gradient(135deg, var(--brand) 0%, #4096ff 100%);
  color: #fff;
  border-radius: var(--radius-bubble-user);
  box-shadow: var(--shadow-blue-lift);
}

.bubble.user:hover {
  box-shadow: var(--shadow-blue-lift);
  transform: translateY(-1px);
}

.message-time {
  font-size: 11px;
  color: var(--text-secondary);
  margin-top: 6px;
  padding: 0 4px;
}

/* ---- 底部输入区 ---- */
.chat-input-area {
  display: flex;
  padding: 16px 24px;
  gap: 12px;
  background: var(--white);
  border-top: 1px solid var(--border-light);
  flex-shrink: 0;
  position: relative;
  z-index: 1;
  box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.05);
}

.chat-input-area input {
  flex: 1;
  min-height: 44px;
  padding: 12px 18px;
  border: 1px solid var(--border-input);
  border-radius: var(--radius-md);
  outline: none;
  font-size: 14px;
  color: var(--text-primary);
  background: var(--list-bg);
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.05);
  transition: all var(--dur-spring) var(--ease-spring);
}

.chat-input-area input:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 4px rgba(22, 119, 255, 0.1),
    inset 0 1px 3px rgba(0, 0, 0, 0.05);
  background: var(--white);
}

.chat-input-area input::placeholder {
  color: var(--text-placeholder);
}

#sendBtn {
  padding: 12px 28px;
  background: linear-gradient(180deg, #2e8cff 0%, var(--brand) 100%);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(22, 119, 255, 0.3);
  transition: all var(--dur-normal) var(--ease-standard);
}

#sendBtn:hover {
  background: linear-gradient(180deg, #4096ff 0%, var(--brand) 100%);
  box-shadow: 0 4px 14px rgba(22, 119, 255, 0.42);
  transform: translateY(-1px);
}

#sendBtn:active {
  background: linear-gradient(180deg, var(--brand) 0%, var(--brand-active) 100%);
  transform: scale(0.96);
  box-shadow: var(--shadow-press);
  transition: all 100ms var(--ease-standard);
}

#sendBtn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  transform: none;
  box-shadow: 0 2px 8px rgba(22, 119, 255, 0.3);
}

/* ================================================================
   4. Ripple 水波纹元素
   ================================================================ */
.ripple-effect {
  position: absolute;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: scale(0);
  animation: rippleExpand var(--dur-ripple) var(--ease-md) forwards;
  pointer-events: none;
}

.sidebar-left .ripple-effect { background: rgba(255, 255, 255, 0.12); }
#sendBtn .ripple-effect      { background: rgba(255, 255, 255, 0.35); }

@keyframes rippleExpand {
  to { transform: scale(4); opacity: 0; }
}

/* ================================================================
   5. 打字指示器
   ================================================================ */
.typing-indicator { align-items: flex-start; }

.typing-bubble {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 14px 18px;
  min-width: 60px;
}

.typing-dots { display: flex; align-items: center; gap: 4px; }

.typing-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-secondary);
  animation: typingBounce 1.4s ease-in-out infinite;
}

.typing-dot:nth-child(1) { animation-delay: 0s; }
.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }

@keyframes typingBounce {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
  30%           { transform: translateY(-6px); opacity: 1; }
}

/* ================================================================
   6. 遮罩层
   ================================================================ */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 90;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease-md);
}

.overlay.show {
  opacity: 1;
  pointer-events: auto;
}

/* ================================================================
   7. 滑出面板（公共）
   ================================================================ */
.panel {
  position: fixed;
  top: 0;
  bottom: 0;
  width: 320px;
  background: var(--white);
  z-index: 100;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-lg);
  transition: transform 0.3s var(--ease-md);
}

.panel-left {
  left: 0;
  transform: translateX(-100%);
}

.panel-left.show {
  transform: translateX(0);
}

.panel-right {
  right: 0;
  transform: translateX(100%);
}

.panel-right.show {
  transform: translateX(0);
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px 16px;
  flex-shrink: 0;
}

.panel-header h3 {
  font-size: 18px;
  font-weight: 650;
  color: var(--text-primary);
}

.panel-close {
  width: 28px;
  height: 28px;
  border: none;
  background: transparent;
  border-radius: 50%;
  cursor: pointer;
  font-size: 16px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--dur-fast) var(--ease-standard);
}

.panel-close:hover {
  background: var(--brand-light);
  color: var(--brand);
}

/* -- 标签页 -- */
.panel-tabs {
  display: flex;
  border-bottom: 1px solid var(--border-light);
  padding: 0 24px;
  gap: 4px;
  flex-shrink: 0;
}

.panel-tab {
  padding: 10px 16px;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  transition: color var(--dur-fast) var(--ease-standard);
}

.panel-tab::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--brand);
  transform: scaleX(0);
  transition: transform 0.2s var(--ease-md);
}

.panel-tab.active {
  color: var(--brand);
}

.panel-tab.active::after {
  transform: scaleX(1);
}

/* -- 面板主体 -- */
.panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 20px 24px;
}

.panel-tab-content {
  display: none;
}

.panel-tab-content.active {
  display: block;
}

/* ================================================================
   8. 主题卡片
   ================================================================ */
.theme-grid {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.theme-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px;
  border: 2px solid var(--border-light);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
  transition: all var(--dur-fast) var(--ease-standard);
}

.theme-card:hover {
  border-color: var(--brand);
  background: var(--brand-light);
}

.theme-card.active {
  border-color: var(--brand);
  background: var(--brand-light);
}

.theme-preview {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.theme-warm-preview {
  background: linear-gradient(135deg, #F5F5F6 0%, #2B2B2B 80%);
}

.theme-ink-preview {
  background: linear-gradient(135deg, #1a1a2e 0%, #4fc3f7 100%);
}

.theme-sakura-preview {
  background: linear-gradient(135deg, #fff5f5 0%, #e8788a 100%);
}

/* ================================================================
   9. 表单元素
   ================================================================ */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-input,
.form-select {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border-input);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--text-primary);
  background: var(--white);
  outline: none;
  transition: border-color var(--dur-fast) var(--ease-standard),
    box-shadow var(--dur-fast) var(--ease-standard);
}

.form-input:focus,
.form-select:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(22, 119, 255, 0.1);
}

.form-select {
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M3 5l3 3 3-3' fill='none' stroke='%236E6E6E' stroke-width='1.5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 32px;
}

.form-hint {
  font-size: 11px;
  color: var(--text-placeholder);
  margin-top: 4px;
}

/* ================================================================
   10. 按钮（操作按钮变体）
   ================================================================ */
.action-group {
  margin-bottom: 20px;
}

.action-desc {
  font-size: 11px;
  color: var(--text-placeholder);
  margin-top: 6px;
}

.action-btn {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--border-input);
  border-radius: var(--radius-sm);
  background: var(--white);
  cursor: pointer;
  font-size: 14px;
  color: var(--text-primary);
  text-align: center;
  transition: all var(--dur-fast) var(--ease-standard);
}

.action-btn:hover {
  border-color: var(--brand);
  background: var(--brand-light);
}

.action-btn-primary {
  background: var(--brand);
  color: #fff;
  border-color: var(--brand);
  font-weight: 600;
}

.action-btn-primary:hover {
  background: var(--brand-hover);
  border-color: var(--brand-hover);
}

.action-btn-danger {
  background: #ff4d4f;
  color: #fff;
  border-color: #ff4d4f;
}

.action-btn-danger:hover {
  background: #cf1322;
  border-color: #cf1322;
}

.action-btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px dashed var(--border-input);
}

.action-btn-ghost:hover {
  border-color: var(--brand);
  color: var(--brand);
  background: transparent;
}

.action-btn-danger-text {
  background: transparent;
  color: #ff4d4f;
  border: 1px solid transparent;
  font-weight: 500;
}

.action-btn-danger-text:hover {
  background: rgba(255, 77, 79, 0.06);
  border-color: rgba(255, 77, 79, 0.25);
  color: #cf1322;
}

/* ================================================================
   11. 模态框
   ================================================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  z-index: 110;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s var(--ease-md);
}

.modal-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  width: 360px;
  max-height: 85vh;
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow-y: auto;
  transform: scale(0.95) translateY(-10px);
  transition: transform 0.25s var(--ease-spring), opacity 0.25s var(--ease-md);
  opacity: 0;
  z-index: 1;
  position: relative;
}

.modal-overlay.show .modal {
  transform: scale(1) translateY(0);
  opacity: 1;
}

.modal-sm {
  width: 340px;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px 0;
}

.modal-header h3 {
  font-size: 18px;
  font-weight: 650;
  color: var(--text-primary);
}

.modal-close {
  width: 28px;
  height: 28px;
  border: none;
  background: transparent;
  border-radius: 50%;
  cursor: pointer;
  font-size: 16px;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--dur-fast) var(--ease-standard);
}

.modal-close:hover {
  background: var(--brand-light);
  color: var(--brand);
}

.modal-body {
  padding: 20px 24px 24px;
}

.modal-divider {
  height: 1px;
  background: var(--border-light);
  margin: 16px 0;
}

/* 确认对话框 */
.confirm-text {
  font-size: 14px;
  color: var(--text-primary);
  line-height: 1.6;
  margin-bottom: 20px;
}

.confirm-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
}

.confirm-actions .action-btn {
  width: auto;
  padding: 10px 24px;
}

/* 关于 Echo — 品牌故事 */
.about-content {
  text-align: center;
}

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

.about-title {
  font-size: 16px;
  font-weight: 650;
  color: var(--text-primary);
  margin-bottom: 16px;
  line-height: 1.5;
}

.about-paragraph {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: 12px;
  text-align: left;
}

.about-paragraph strong {
  color: var(--brand);
  font-weight: 600;
}

.about-paragraph em {
  font-style: italic;
  color: var(--text-primary);
}

.about-divider {
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--brand), transparent);
  margin: 16px auto;
}

.about-motto {
  font-size: 13px;
  color: var(--brand);
  line-height: 1.8;
  text-align: center;
}

.about-motto strong {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-primary);
}

/* ================================================================
   12. 文件拖拽区
   ================================================================ */
.file-drop-zone {
  border: 2px dashed var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  text-align: center;
  cursor: pointer;
  transition: all var(--dur-fast) var(--ease-standard);
  margin-bottom: 24px;
}

.file-drop-zone:hover,
.file-drop-zone.drag-over {
  border-color: var(--brand);
  background: var(--brand-light);
}

.file-drop-icon {
  font-size: 32px;
  display: block;
  margin-bottom: 8px;
}

.file-drop-text {
  font-size: 13px;
  color: var(--text-primary);
  margin-bottom: 4px;
}

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

/* ================================================================
   13. 外部平台导出指南
   ================================================================ */
.export-guides h4 {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.guide-section {
  margin-bottom: 16px;
  padding: 12px;
  background: var(--list-bg);
  border-radius: var(--radius-sm);
}

.guide-platform {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.guide-steps {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 4px;
}

.guide-link {
  font-size: 12px;
  color: var(--brand);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-standard);
}

.guide-link:hover {
  color: var(--brand-hover);
  text-decoration: underline;
}

/* ================================================================
   14. Toast 提示
   ================================================================ */
.toast {
  position: fixed;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: #333;
  color: #fff;
  padding: 10px 24px;
  border-radius: var(--radius-pill);
  font-size: 13px;
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease-md), transform 0.3s var(--ease-spring);
  white-space: nowrap;
}

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

/* ================================================================
   15. 滚动条美化
   ================================================================ */
.chat-messages::-webkit-scrollbar,
.chat-list::-webkit-scrollbar,
.panel-body::-webkit-scrollbar,
.modal::-webkit-scrollbar {
  width: 5px;
}

.chat-messages::-webkit-scrollbar-track,
.chat-list::-webkit-scrollbar-track,
.panel-body::-webkit-scrollbar-track,
.modal::-webkit-scrollbar-track {
  background: transparent;
}

.chat-messages::-webkit-scrollbar-thumb,
.chat-list::-webkit-scrollbar-thumb,
.panel-body::-webkit-scrollbar-thumb,
.modal::-webkit-scrollbar-thumb {
  background: rgba(0, 0, 0, 0.12);
  border-radius: 3px;
}

.chat-messages::-webkit-scrollbar-thumb:hover,
.chat-list::-webkit-scrollbar-thumb:hover,
.panel-body::-webkit-scrollbar-thumb:hover,
.modal::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 0, 0, 0.24);
}

/* ================================================================
   16. 响应式：小屏适配
   ================================================================ */
@media (max-width: 1024px) {
  .chat-list { width: 200px; }
  .panel-left, .panel-right { width: 280px; }
}

/* ================================================================
   16b. 移动端适配（≤768px）
   ================================================================ */
@media (max-width: 768px) {
  /* -- 布局重置：桌面端区域隐藏 -- */
  .app {
    display: none;
  }

  body {
    overflow: hidden;
  }

  /* -- 联系人页头像按钮 -- */
  .mobile-header-avatar {
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background: linear-gradient(145deg, #4096FF, var(--brand));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    flex-shrink: 0;
    background-size: cover;
    background-position: center;
  }

  /* -- 移动端全屏页面容器 -- */
  .mobile-page {
    display: none;
    position: fixed;
    inset: 0;
    background: var(--white);
    z-index: 15;
    flex-direction: column;
    overflow: hidden;
  }

  .mobile-page.show {
    display: flex;
  }

  .mobile-page-header {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-light);
    gap: 12px;
    flex-shrink: 0;
    min-height: 52px;
  }

  .mobile-page-header h3 {
    font-size: 18px;
    font-weight: 650;
    color: var(--text-primary);
  }

  .mobile-back-btn {
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    border-radius: 50%;
    cursor: pointer;
    font-size: 22px;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all var(--dur-fast) var(--ease-standard);
  }

  .mobile-back-btn:hover {
    color: var(--brand);
    background: var(--brand-light);
  }

  .mobile-back-btn:active {
    transform: scale(0.9);
    transition: all 100ms var(--ease-standard);
  }

  /* -- 联系人列表 -- */
  .mobile-contacts-list {
    flex: 1;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .mobile-contacts-list .conversation {
    margin: 2px 8px;
  }

  /* -- 移动端聊天区域 -- */
  #mobileChatMessages {
    flex: 1;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    padding: 16px 12px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    background: var(--chat-bg);
  }

  /* -- 消息区域（两端共用） -- */
  .chat-messages,
  #mobileChatMessages {
    padding: 16px 12px;
    gap: 12px;
  }

  .bubble {
    max-width: 85%;
  }

  /* -- 输入区域（两端共用） -- */
  .chat-input-area {
    padding: 10px 12px;
    gap: 8px;
  }

  .chat-input-area input {
    min-height: 44px;
    padding: 10px 14px;
    font-size: 16px;
  }

  #sendBtn,
  #mobileSendBtn {
    padding: 10px 20px;
    font-size: 14px;
  }

  #mobileSendBtn {
    background: linear-gradient(180deg, #2e8cff 0%, var(--brand) 100%);
    color: #fff;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-weight: 600;
    white-space: nowrap;
    box-shadow: 0 2px 8px rgba(22, 119, 255, 0.3);
    transition: all var(--dur-normal) var(--ease-standard);
  }

  #mobileSendBtn:hover {
    box-shadow: 0 4px 14px rgba(22, 119, 255, 0.42);
    transform: translateY(-1px);
  }

  #mobileSendBtn:active {
    transform: scale(0.96);
    transition: all 100ms var(--ease-standard);
  }

  #mobileSendBtn:disabled {
    opacity: 0.45;
    cursor: not-allowed;
  }

  /* -- 面板：移动端全屏宽度 -- */
  .panel {
    width: 100vw;
  }

  /* -- 模态框：移动端适配 -- */
  .modal {
    width: calc(100vw - 32px);
    max-width: 360px;
    margin: 0 auto;
  }

  .intro-modal {
    width: calc(100vw - 32px);
    max-width: 360px;
  }

  .intro-body {
    padding: 24px 20px 20px;
  }

  .intro-avatar {
    width: 64px;
    height: 64px;
    font-size: 32px;
  }

  .intro-title {
    font-size: 18px;
  }

  .intro-text p {
    font-size: 13px;
  }

  .modal-sm {
    width: calc(100vw - 48px);
    max-width: 340px;
  }

  /* -- 下拉菜单：移动端全宽对齐 -- */
  .dropdown-menu {
    width: 220px;
  }

  /* -- Toast 移动端 -- */
  .toast {
    bottom: 40px;
  }

  /* -- 抽屉 -- */
  .drawer-overlay {
    opacity: 1;
    pointer-events: auto;
  }

  .drawer {
    width: 75vw;
    max-width: 300px;
  }

  /* -- 移动端 AI 设置弹出层 -- */
  .ai-settings-mobile-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    z-index: 150;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s var(--ease-md);
  }

  .ai-settings-mobile-overlay.show {
    opacity: 1;
    pointer-events: auto;
  }

  .ai-settings-mobile {
    position: fixed !important;
    top: 50% !important;
    left: 50% !important;
    transform: translate(-50%, -50%) !important;
    width: calc(100vw - 40px) !important;
    max-width: 360px !important;
    background: var(--white) !important;
    border-radius: var(--radius-lg) !important;
    box-shadow: var(--shadow-lg) !important;
    padding: 20px 24px !important;
    z-index: 160 !important;
    display: block !important;
  }
}

/* 桌面端隐藏移动端页面 */
.mobile-page {
  display: none;
}

/* ================================================================
   16c. 抽屉菜单（移动端左侧滑出）
   ================================================================ */
.drawer-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 95;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease-md);
}

.drawer-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

.drawer {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  width: 75vw;
  max-width: 300px;
  background: var(--white);
  z-index: 100;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-lg);
  transform: translateX(-100%);
  transition: transform 0.3s var(--ease-md);
}

.drawer.show {
  transform: translateX(0);
}

.drawer-header {
  padding: 40px 24px 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid var(--border-light);
  flex-shrink: 0;
}

.drawer-avatar {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: linear-gradient(145deg, #4096FF, var(--brand));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 24px;
  font-weight: 700;
  background-size: cover;
  background-position: center;
  box-shadow: 0 4px 16px rgba(22, 119, 255, 0.3);
  cursor: pointer;
}

.drawer-name {
  font-size: 16px;
  font-weight: 650;
  color: var(--text-primary);
}

.drawer-menu {
  flex: 1;
  overflow-y: auto;
  padding: 12px 0;
}

.drawer-item {
  width: 100%;
  padding: 14px 24px;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 15px;
  color: var(--text-primary);
  text-align: left;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: background var(--dur-fast) var(--ease-standard);
}

.drawer-item:hover {
  background: var(--brand-light);
}

.drawer-item:active {
  background: var(--brand-glow);
}

/* ================================================================
   16d. 头像上传
   ================================================================ */
.avatar-upload {
  display: flex;
  align-items: center;
  gap: 14px;
}

.avatar-preview {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: linear-gradient(145deg, #4096FF, var(--brand));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 20px;
  font-weight: 700;
  flex-shrink: 0;
  background-size: cover;
  background-position: center;
  box-shadow: 0 2px 10px rgba(22, 119, 255, 0.3);
}

/* 联系人页头像按钮 */
.mobile-header-avatar {
  display: none;
  position: relative;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(145deg, #4096FF, var(--brand));
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  flex-shrink: 0;
  background-size: cover;
  background-position: center;
}

@media (max-width: 768px) {
  .mobile-header-avatar {
    display: flex;
  }
}

/* 温度帮助按钮 */
.temp-help-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 18px;
  height: 18px;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 12px;
  padding: 0;
  margin-left: 4px;
  border-radius: 50%;
  transition: all var(--dur-fast) var(--ease-standard);
  vertical-align: middle;
  color: var(--text-placeholder);
}

.temp-help-btn:hover {
  background: var(--brand-light);
  color: var(--brand);
}

/* ================================================================
   17. 键盘导航：焦点可见样式
   ================================================================ */
.nav-btn:focus-visible,
.chat-settings:focus-visible,
#sendBtn:focus-visible,
.user-avatar:focus-visible,
.panel-close:focus-visible,
.modal-close:focus-visible,
.panel-tab:focus-visible,
.theme-card:focus-visible,
.action-btn:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

.chat-input-area input:focus-visible,
.form-input:focus-visible,
.form-select:focus-visible,
.search-box input:focus-visible {
  outline: none;
  border-color: var(--brand);
  box-shadow: 0 0 0 4px rgba(22, 119, 255, 0.1),
    inset 0 1px 3px rgba(0, 0, 0, 0.05);
}

/* ================================================================
   18. 头像光晕引导动画（任务 2.2）
   ================================================================ */

/* -- 基础动画：头像缩放呼吸 + 外围光晕 -- */
.avatar-glow-guide {
  animation: avatarGlowPulse 2s var(--ease-spring) 4;
}

@keyframes avatarGlowPulse {
  0%   { transform: scale(1.0); box-shadow: 0 0 0 0 rgba(22, 119, 255, 0.6), 0 2px 10px rgba(22, 119, 255, 0.4); }
  20%  { transform: scale(1.12); box-shadow: 0 0 16px 6px rgba(22, 119, 255, 0.5), 0 2px 20px rgba(22, 119, 255, 0.5); }
  40%  { transform: scale(1.0); box-shadow: 0 0 0 0 rgba(22, 119, 255, 0.6), 0 2px 10px rgba(22, 119, 255, 0.4); }
  100% { transform: scale(1.0); box-shadow: 0 0 0 0 rgba(22, 119, 255, 0.6), 0 2px 10px rgba(22, 119, 255, 0.4); }
}

/* -- 外围环形光晕呼吸 -- */
@keyframes avatarRingBreathe {
  0%   { opacity: 0.3; }
  20%  { opacity: 1; }
  40%  { opacity: 0.3; }
  100% { opacity: 0.3; }
}

/* -- 环形光晕（桌面端 .user-avatar） -- */
.user-avatar::before {
  content: "";
  position: absolute;
  inset: -6px;
  border-radius: inherit;
  border: 3px solid rgba(22, 119, 255, 0.4);
  box-shadow: 0 0 12px rgba(22, 119, 255, 0.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease-spring);
}

.user-avatar.avatar-glow-guide::before {
  opacity: 1;
  animation: avatarRingBreathe 2s var(--ease-spring) 4;
}

/* -- 环形光晕（移动端 .mobile-header-avatar） -- */
.mobile-header-avatar::before {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: inherit;
  border: 2.5px solid rgba(22, 119, 255, 0.4);
  box-shadow: 0 0 8px rgba(22, 119, 255, 0.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease-spring);
}

.mobile-header-avatar.avatar-glow-guide::before {
  opacity: 1;
  animation: avatarRingBreathe 2s var(--ease-spring) 4;
}

/* ================================================================
   19. 开屏弹窗（任务 3 — 首次访问介绍）
   ================================================================ */
.intro-modal {
  width: 400px;
  text-align: center;
}

.intro-body {
  padding: 32px 28px 28px;
}

.intro-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: linear-gradient(145deg, #4096FF, var(--brand));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 40px;
  margin: 0 auto 20px;
  box-shadow: 0 4px 20px rgba(22, 119, 255, 0.25);
}

.intro-title {
  font-size: 20px;
  font-weight: 650;
  color: var(--text-primary);
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}

.intro-text {
  text-align: left;
  margin-bottom: 24px;
}

.intro-text p {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: 12px;
}

.intro-text p:last-child {
  margin-bottom: 0;
}

.intro-start-btn {
  width: 100%;
  padding: 14px 16px;
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 16px;
}

.intro-api-hint {
  margin-top: 4px;
}

.intro-api-hint p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.intro-api-link {
  color: var(--brand);
  text-decoration: none;
  font-weight: 500;
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease-standard);
}

.intro-api-link:hover {
  color: var(--brand-hover);
  text-decoration: underline;
}

/* ================================================================
   20. 次要按钮样式
   ================================================================ */
.action-btn-secondary {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-light);
  font-weight: 500;
}

.action-btn-secondary:hover {
  border-color: var(--brand);
  color: var(--brand);
  background: var(--brand-light);
}

/* ================================================================
   21. 设置分隔线 + 开关样式
   ================================================================ */
.setting-divider {
  height: 1px;
  background: var(--border-light);
  margin: 20px 0;
}

.toggle-label {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-primary);
  user-select: none;
}

.toggle-label input[type="checkbox"] {
  display: none;
}

.toggle-switch {
  width: 40px;
  height: 22px;
  border-radius: 11px;
  background: var(--border-light);
  position: relative;
  flex-shrink: 0;
  transition: background var(--dur-fast) var(--ease-standard);
}

.toggle-switch::after {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--white);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
  transition: transform var(--dur-fast) var(--ease-spring);
}

.toggle-label input:checked + .toggle-switch {
  background: var(--brand);
}

.toggle-label input:checked + .toggle-switch::after {
  transform: translateX(18px);
}

/* ================================================================
   22. 危险操作区域
   ================================================================ */
.danger-zone {
  padding: 0;
}

.danger-zone-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 10px;
}

/* ================================================================
   23. 开源信息
   ================================================================ */
.opensource-info {
  padding: 0;
}

.opensource-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.opensource-links {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.8;
}

.opensource-link {
  color: var(--brand);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-standard);
}

.opensource-link:hover {
  color: var(--brand-hover);
  text-decoration: underline;
}

.opensource-desc {
  font-size: 11px;
  color: var(--text-placeholder);
  margin-top: 10px;
  line-height: 1.5;
}

/* ================================================================
   24. 无障碍：减少动画偏好
   ================================================================ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ================================================================
   25. 棱镜气泡样式 — 绿色渐变，区别于 Echo 的灰色
   ================================================================ */
.bubble.lens {
  background: linear-gradient(135deg, #e8f5e9, #f1f8e9);
  border: 1px solid #a5d6a7;
  color: #1b5e20;
  border-radius: var(--radius-bubble-ai);
  box-shadow: 0 1px 3px rgba(76, 175, 80, 0.12);
}
.bubble.lens:hover {
  background: #d7eed8;
  box-shadow: 0 4px 12px rgba(76, 175, 80, 0.18);
}
.bubble.lens::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: rgba(76, 175, 80, 0.25);
  border-radius: 1px;
  pointer-events: none;
}
.message.lens {
  align-items: flex-start;
}