/* =====================================================
   睡眠养生双站 — 共享设计系统
   参考: thisworks / mantasleep / bearaby / smartsleep
   风格: 简约治愈 · 大地色系 · 柔和圆润
   ===================================================== */

/* ---- CSS 变量 ---- */
:root {
  /* 主色调 — 自然大地 */
  --clr-cream: #F9F5EF;
  --clr-sand: #EDE5D8;
  --clr-warm-beige: #D9CDBF;
  --clr-sage: #9BAF9B;
  --clr-sage-deep: #6E8F6E;
  --clr-moss: #4A6741;
  --clr-night: #2C3B35;
  --clr-midnight: #1A2520;

  /* 强调色 */
  --clr-lavender: #C5B8D4;
  --clr-blush: #E8C9BE;
  --clr-gold: #C9A96E;

  /* 文字 */
  --clr-text-primary: #2C3B35;
  --clr-text-secondary: #5A6B62;
  --clr-text-muted: #8A9B92;
  --clr-text-inverse: #F9F5EF;

  /* 背景 */
  --clr-bg-page: #F9F5EF;
  --clr-bg-card: #FFFFFF;
  --clr-bg-section: #F2EDE4;

  /* 字体 */
  --font-display: 'Cormorant Garamond', 'Noto Serif SC', Georgia, serif;
  --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;

  /* 间距 */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-xxl: 7rem;

  /* 圆角 */
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 32px;
  --radius-pill: 999px;

  /* 阴影 */
  --shadow-sm: 0 2px 12px rgba(44,59,53,0.06);
  --shadow-md: 0 8px 32px rgba(44,59,53,0.10);
  --shadow-lg: 0 20px 60px rgba(44,59,53,0.14);

  /* 过渡 */
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);

  /* 容器 */
  --max-w: 1280px;
  --nav-h: 72px;
}

/* ---- 暗色模式 (夜间阅读) ---- */
@media (prefers-color-scheme: dark) {
  :root {
    --clr-bg-page: #1A2520;
    --clr-bg-card: #232E28;
    --clr-bg-section: #1F2B25;
    --clr-text-primary: #EDE5D8;
    --clr-text-secondary: #B0BFB5;
    --clr-text-muted: #6E8070;
  }
}

/* ---- 重置 & 基础 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  background: var(--clr-bg-page);
  color: var(--clr-text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

img, video { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { cursor: pointer; font-family: inherit; border: none; background: none; }
input, textarea, select { font-family: inherit; }
ul, ol { list-style: none; }

/* ---- 容器 ---- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ---- 通用按钮 ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 2rem;
  border-radius: var(--radius-pill);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  transition: var(--transition);
  cursor: pointer;
}

.btn-primary {
  background: var(--clr-night);
  color: var(--clr-cream);
}
.btn-primary:hover { background: var(--clr-moss); transform: translateY(-2px); box-shadow: var(--shadow-md); }

.btn-outline {
  border: 1.5px solid var(--clr-night);
  color: var(--clr-night);
}
.btn-outline:hover { background: var(--clr-night); color: var(--clr-cream); transform: translateY(-2px); }

.btn-sage {
  background: var(--clr-sage);
  color: var(--clr-cream);
}
.btn-sage:hover { background: var(--clr-sage-deep); transform: translateY(-2px); }

.btn-gold {
  background: var(--clr-gold);
  color: #fff;
}
.btn-gold:hover { filter: brightness(1.08); transform: translateY(-2px); }

/* ---- 排版 ---- */
.heading-display {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6vw, 5rem);
  font-weight: 300;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.heading-h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.5vw, 2.8rem);
  font-weight: 400;
  line-height: 1.2;
}

.heading-h3 {
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  font-weight: 600;
  line-height: 1.3;
}

.label-tag {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--clr-sage-deep);
}

/* ---- 导航栏 ---- */
.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(249,245,239,0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(44,59,53,0.08);
  z-index: 1000;
  transition: var(--transition);
}

.site-nav.scrolled {
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.nav-logo {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}
.nav-logo .logo-main {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--clr-night);
  letter-spacing: 0.02em;
}
.nav-logo .logo-sub {
  font-size: 0.62rem;
  letter-spacing: 0.18em;
  color: var(--clr-text-muted);
  text-transform: uppercase;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-links a {
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--clr-text-secondary);
  transition: var(--transition);
  white-space: nowrap;
}
.nav-links a:hover, .nav-links a.active {
  background: var(--clr-sand);
  color: var(--clr-night);
}

.nav-links a.nav-ai {
  background: var(--clr-sage);
  color: white;
  margin-left: 0.5rem;
}
.nav-links a.nav-ai:hover { background: var(--clr-sage-deep); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-lang-switch {
  font-size: 0.78rem;
  color: var(--clr-text-muted);
  border: 1px solid var(--clr-warm-beige);
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-pill);
  transition: var(--transition);
}
.nav-lang-switch:hover { border-color: var(--clr-sage); color: var(--clr-sage-deep); }

/* 汉堡菜单 */
.nav-burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  cursor: pointer;
}
.nav-burger span {
  display: block;
  height: 2px;
  background: var(--clr-night);
  border-radius: 2px;
  transition: var(--transition);
}

/* 移动菜单 */
.mobile-menu {
  display: none;
  position: fixed;
  top: var(--nav-h);
  left: 0; right: 0;
  background: rgba(249,245,239,0.98);
  backdrop-filter: blur(20px);
  padding: var(--space-md);
  z-index: 999;
  border-bottom: 1px solid var(--clr-sand);
  flex-direction: column;
  gap: 0.5rem;
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  font-weight: 500;
  color: var(--clr-text-primary);
  transition: var(--transition);
}
.mobile-menu a:hover { background: var(--clr-sand); }

/* ---- 卡片 ---- */
.card {
  background: var(--clr-bg-card);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.card:hover { box-shadow: var(--shadow-md); transform: translateY(-4px); }

.card-img {
  width: 100%;
  aspect-ratio: 16/10;
  object-fit: cover;
}

.card-body { padding: var(--space-md); }

/* ---- 章节间距 ---- */
.section { padding: var(--space-xxl) 0; }
.section-sm { padding: var(--space-xl) 0; }

/* ---- 分隔线 ---- */
.divider {
  width: 48px;
  height: 2px;
  background: var(--clr-sage);
  margin: var(--space-sm) 0;
}
.divider-center { margin: var(--space-sm) auto; }

/* ---- 标签 ---- */
.tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-pill);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  background: var(--clr-sand);
  color: var(--clr-text-secondary);
}
.tag-sage { background: rgba(155,175,155,0.2); color: var(--clr-sage-deep); }
.tag-lavender { background: rgba(197,184,212,0.2); color: #7B6A95; }
.tag-blush { background: rgba(232,201,190,0.2); color: #9E6E60; }

/* ---- 免责声明横幅 ---- */
.disclaimer-banner {
  background: rgba(155,175,155,0.12);
  border-left: 3px solid var(--clr-sage);
  padding: 0.75rem 1.25rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.78rem;
  color: var(--clr-text-secondary);
  line-height: 1.6;
}

/* ---- Footer ---- */
.site-footer {
  background: var(--clr-night);
  color: var(--clr-text-inverse);
  padding: var(--space-xl) 0 var(--space-lg);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-xl);
}

.footer-brand .logo-main {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 300;
}

.footer-brand p {
  font-size: 0.85rem;
  color: rgba(249,245,239,0.5);
  margin-top: 0.75rem;
  line-height: 1.8;
}

.footer-links h4 {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(249,245,239,0.4);
  margin-bottom: 1rem;
}

.footer-links a {
  display: block;
  font-size: 0.88rem;
  color: rgba(249,245,239,0.7);
  padding: 0.3rem 0;
  transition: var(--transition);
}
.footer-links a:hover { color: var(--clr-sage); }

.footer-bottom {
  margin-top: var(--space-lg);
  padding-top: var(--space-sm);
  border-top: 1px solid rgba(249,245,239,0.08);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  font-size: 0.78rem;
  color: rgba(249,245,239,0.35);
}

/* ---- AI 悬浮聊天按钮 ---- */
.ai-chat-fab {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 900;
}

.ai-chat-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--clr-sage), var(--clr-moss));
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 32px rgba(74,103,65,0.4);
  transition: var(--transition);
  cursor: pointer;
  border: none;
}
.ai-chat-btn:hover { transform: scale(1.08); box-shadow: 0 12px 40px rgba(74,103,65,0.5); }

.ai-chat-btn svg { width: 26px; height: 26px; fill: white; }

.ai-chat-window {
  display: none;
  position: absolute;
  bottom: 76px;
  right: 0;
  width: 360px;
  max-height: 520px;
  background: white;
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.18);
  overflow: hidden;
  flex-direction: column;
}
.ai-chat-window.open { display: flex; }

.chat-header {
  background: linear-gradient(135deg, var(--clr-night), var(--clr-moss));
  color: white;
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.chat-header-icon {
  width: 36px; height: 36px;
  background: rgba(255,255,255,0.15);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem;
}
.chat-header-text .name { font-weight: 600; font-size: 0.9rem; }
.chat-header-text .status { font-size: 0.72rem; opacity: 0.7; }

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  background: #F8F7F5;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  min-height: 200px;
}

.chat-bubble {
  max-width: 80%;
  padding: 0.65rem 1rem;
  border-radius: 16px;
  font-size: 0.85rem;
  line-height: 1.6;
}
.chat-bubble.bot {
  background: white;
  align-self: flex-start;
  border-bottom-left-radius: 4px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.06);
}
.chat-bubble.user {
  background: var(--clr-sage);
  color: white;
  align-self: flex-end;
  border-bottom-right-radius: 4px;
}

.chat-input-area {
  padding: 0.75rem;
  background: white;
  border-top: 1px solid #F0EDED;
  display: flex;
  gap: 0.5rem;
}
.chat-input-area input {
  flex: 1;
  border: 1.5px solid #E8E4E0;
  border-radius: var(--radius-pill);
  padding: 0.6rem 1rem;
  font-size: 0.85rem;
  outline: none;
  transition: var(--transition);
}
.chat-input-area input:focus { border-color: var(--clr-sage); }
.chat-send-btn {
  width: 38px; height: 38px;
  border-radius: 50%;
  background: var(--clr-sage);
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
  flex-shrink: 0;
}
.chat-send-btn:hover { background: var(--clr-moss); }
.chat-send-btn svg { width: 16px; height: 16px; fill: white; }

/* ---- 响应式 ---- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
  :root { --nav-h: 64px; }
  .nav-links, .nav-lang-switch { display: none; }
  .nav-burger { display: flex; }
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-lg); }
  .ai-chat-window { width: calc(100vw - 4rem); right: 0; }
}

@media (max-width: 480px) {
  .container { padding: 0 1rem; }
  .ai-chat-fab { bottom: 1rem; right: 1rem; }
}

/* ---- 动画 ---- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.animate-fade-up { animation: fadeInUp 0.7s ease both; }
.animate-float { animation: float 6s ease-in-out infinite; }

/* ---- 滚动动画触发 ---- */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ---- 图片占位（渐变代替真实图片）---- */
.img-placeholder {
  border-radius: var(--radius-md);
  overflow: hidden;
}
.hero-bg {
  background: linear-gradient(135deg, #D4E6D4 0%, #EDE5D8 40%, #C5D0C8 100%);
}
.nature-bg-1 { background: linear-gradient(135deg, #B8D4B8 0%, #8FAF8F 100%); }
.nature-bg-2 { background: linear-gradient(135deg, #D4C4E4 0%, #B8A8CC 100%); }
.nature-bg-3 { background: linear-gradient(135deg, #E8D4C0 0%, #C8B090 100%); }
.nature-bg-4 { background: linear-gradient(135deg, #C8D8E8 0%, #A0B8CC 100%); }
.nature-bg-5 { background: linear-gradient(135deg, #E4DCD4 0%, #C8BFB8 100%); }

/* ---- 播放器样式 ---- */
.audio-card {
  background: var(--clr-bg-card);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  display: flex;
  align-items: center;
  gap: 1rem;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.audio-card:hover { box-shadow: var(--shadow-md); }

.audio-art {
  width: 64px; height: 64px;
  border-radius: var(--radius-md);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
}

.audio-info { flex: 1; min-width: 0; }
.audio-info .title { font-weight: 600; font-size: 0.9rem; margin-bottom: 0.25rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.audio-info .meta { font-size: 0.75rem; color: var(--clr-text-muted); }

.audio-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.play-btn {
  width: 42px; height: 42px;
  border-radius: 50%;
  background: var(--clr-night);
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
  cursor: pointer;
}
.play-btn:hover { background: var(--clr-moss); transform: scale(1.06); }
.play-btn svg { width: 16px; height: 16px; fill: white; margin-left: 2px; }

/* ---- 进度条 ---- */
.progress-bar {
  width: 100%;
  height: 3px;
  background: var(--clr-sand);
  border-radius: 3px;
  margin-top: 0.5rem;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: var(--clr-sage);
  border-radius: 3px;
  transition: width 0.1s linear;
}