/* ═══════════════════════════════════════════════════════════════
   轻梦 Light Dream — 全局样式系统 v2
   设计基调：暮光梦境 — 柔和、宁静、治愈
   配色方向：暮光蓝 + 温暖底色 + 星辉金点缀
   ═══════════════════════════════════════════════════════════════ */

/* ── CSS 变量 / 设计令牌 ── */
:root {
  /* ═══ 主色系 — 暮光蓝（低饱和度、柔和、不刺眼） ═══ */
  --primary: #7B9CC8;
  --primary-dark: #5F7FA8;
  --primary-darker: #435F80;
  --primary-light: #E8EFF8;
  --primary-lighter: #F4F7FB;

  /* ═══ 点缀色 ═══ */
  --secondary: #A095C8;        /* 柔和薰衣草 */
  --secondary-light: #F0EDF8;
  --accent: #D4A76A;           /* 星辉暖金 */
  --accent-light: #FBF5EC;
  --accent-soft: #E8C9A0;      /* 浅金色 */

  /* ═══ 中性色 — 暖灰底调 ═══ */
  --bg: #FAF8F5;
  --bg-alt: #F5F2EF;
  --surface: #FFFFFF;
  --text: #3A3547;
  --text-secondary: #7A7588;
  --text-muted: #B0ABB8;
  --border: #E8E4DF;
  --border-light: #F2EFEB;

  /* ═══ 渐变 ═══ */
  --gradient-primary: linear-gradient(135deg, #7B9CC8 0%, #A095C8 100%);
  --gradient-hero: linear-gradient(165deg, #E8EFF8 0%, #EDE8F5 30%, #FBF5EC 60%, #F4F7FB 100%);
  --gradient-banner: linear-gradient(160deg, #6B8BBE 0%, #8BA0CC 40%, #A095C8 100%);
  --gradient-dark: linear-gradient(160deg, #2D2A3A 0%, #3A3550 50%, #2D2A40 100%);
  --gradient-card: linear-gradient(135deg, rgba(123,156,200,0.03) 0%, rgba(160,149,200,0.03) 100%);
  --gradient-glow: radial-gradient(ellipse at center, rgba(212,167,106,0.08) 0%, transparent 70%);

  /* ═══ 阴影 — 柔和暖调 ═══ */
  --shadow-xs: 0 1px 3px rgba(58,53,71,0.03);
  --shadow-sm: 0 2px 8px rgba(58,53,71,0.05);
  --shadow-md: 0 4px 20px rgba(58,53,71,0.06);
  --shadow-lg: 0 8px 40px rgba(58,53,71,0.07);
  --shadow-xl: 0 16px 60px rgba(58,53,71,0.08);
  --shadow-glow: 0 0 50px rgba(123,156,200,0.12);

  /* ═══ 圆角 ═══ */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-full: 100px;

  /* ═══ 间距 ═══ */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 64px;
  --space-2xl: 96px;

  /* ═══ 过渡 ═══ */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --duration-fast: 150ms;
  --duration: 300ms;
  --duration-slow: 500ms;
}

/* ── 全局重置 ── */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Noto Sans SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.8;
  overflow-x: hidden;
  font-size: 16px;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

/* ── 通用容器 ── */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.container-sm {
  max-width: 800px;
}

.container-lg {
  max-width: 1320px;
}

/* ── Section 通用 ── */
.section {
  padding: var(--space-2xl) var(--space-md);
}

.section-sm {
  padding: var(--space-xl) var(--space-md);
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.section-header .label {
  display: inline-block;
  padding: 6px 18px;
  background: var(--primary-light);
  color: var(--primary-dark);
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 1px;
  margin-bottom: var(--space-sm);
}

.section-header h2 {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  color: var(--text);
  line-height: 1.35;
  letter-spacing: 1px;
}

.section-header h2 span {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-header p {
  margin-top: var(--space-sm);
  font-size: 17px;
  color: var(--text-secondary);
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

/* ── 导航栏 ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(250,248,245,0.82);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: all var(--duration) var(--ease-out);
  height: 68px;
}

.nav.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-xs);
  background: rgba(250,248,245,0.94);
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 2px;
}

.nav-logo .logo-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: #fff;
}

.nav-logo .logo-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
  list-style: none;
}

.nav-links a {
  display: inline-flex;
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--duration-fast) var(--ease-out);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary-dark);
  background: var(--primary-light);
}

.nav-cta {
  padding: 10px 22px !important;
  background: var(--gradient-primary) !important;
  color: #fff !important;
  font-weight: 600 !important;
  box-shadow: 0 4px 14px rgba(123,156,200,0.3);
}

.nav-cta:hover {
  box-shadow: 0 6px 20px rgba(123,156,200,0.4) !important;
  transform: translateY(-1px);
  background: var(--gradient-primary) !important;
  color: #fff !important;
}

/* 移动端菜单 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
  background: none;
  border: none;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--duration) var(--ease-out);
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ── 按钮系统 ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: var(--radius-full);
  font-size: 15px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all var(--duration) var(--ease-out);
  white-space: nowrap;
  letter-spacing: 0.3px;
}

.btn-primary {
  background: var(--gradient-primary);
  color: #fff;
  box-shadow: 0 4px 16px rgba(123,156,200,0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(123,156,200,0.45);
}

.btn-secondary {
  background: var(--primary-light);
  color: var(--primary-dark);
}

.btn-secondary:hover {
  background: #DEE6F2;
  transform: translateY(-1px);
}

.btn-outline {
  background: transparent;
  border: 1.5px solid var(--border);
  color: var(--text);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary-dark);
  background: var(--primary-lighter);
}

.btn-white {
  background: #fff;
  color: var(--primary-dark);
  box-shadow: var(--shadow-sm);
}

.btn-white:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 16px 40px;
  font-size: 17px;
}

.btn-sm {
  padding: 10px 22px;
  font-size: 13px;
}

/* ── 页面 Banner（非首页通用） ── */
.page-banner {
  padding: 140px var(--space-md) 80px;
  background: var(--gradient-banner);
  text-align: center;
  color: #fff;
  position: relative;
  overflow: hidden;
}

.page-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 50%, rgba(255,255,255,0.08) 0%, transparent 50%),
    radial-gradient(circle at 80% 50%, rgba(255,255,255,0.04) 0%, transparent 50%);
  pointer-events: none;
}

.page-banner h1 {
  font-size: clamp(30px, 5vw, 48px);
  font-weight: 700;
  margin-bottom: var(--space-sm);
  position: relative;
}

.page-banner p {
  font-size: 18px;
  opacity: 0.85;
  max-width: 560px;
  margin: 0 auto;
  position: relative;
}

/* ── 卡片系统 ── */
.card {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: var(--space-lg);
  transition: all var(--duration) var(--ease-out);
}

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

.card-glass {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.8);
}

/* ── 标签系统 ── */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.3px;
}

.tag-done {
  background: #EDF4EE;
  color: #5A8A62;
}

.tag-progress {
  background: #FDF6EC;
  color: #C08850;
}

.tag-plan {
  background: var(--secondary-light);
  color: #8B7EB8;
}

.tag-new {
  background: var(--accent-light);
  color: #B08850;
}

/* ── 统计数字 ── */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
}

.stat-item {
  text-align: center;
  padding: var(--space-lg) var(--space-md);
  background: var(--surface);
  border-radius: var(--radius);
  border: 1px solid var(--border-light);
  transition: all var(--duration) var(--ease-out);
}

.stat-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.stat-number {
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 800;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
}

.stat-label {
  margin-top: 6px;
  font-size: 14px;
  color: var(--text-secondary);
}

/* ── Footer ── */
.footer {
  background: #2D2A3A;
  color: rgba(255, 255, 255, 0.65);
  padding: var(--space-2xl) var(--space-md) var(--space-lg);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-xl);
  max-width: 1200px;
  margin: 0 auto;
}

.footer h4 {
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  margin-bottom: var(--space-md);
}

.footer a {
  display: block;
  padding: 4px 0;
  color: rgba(255, 255, 255, 0.55);
  font-size: 14px;
  transition: color var(--duration-fast);
}

.footer a:hover {
  color: var(--accent-soft);
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.8;
  margin-top: var(--space-sm);
}

.footer-bottom {
  max-width: 1200px;
  margin: var(--space-xl) auto 0;
  padding-top: var(--space-md);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.35);
}

/* ── 渐变文字 ── */
.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ── 动画 ── */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

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

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-in {
  animation: fadeInUp 0.6s var(--ease-out) forwards;
  opacity: 0;
}

.animate-in:nth-child(1) { animation-delay: 0.1s; }
.animate-in:nth-child(2) { animation-delay: 0.2s; }
.animate-in:nth-child(3) { animation-delay: 0.3s; }
.animate-in:nth-child(4) { animation-delay: 0.4s; }
.animate-in:nth-child(5) { animation-delay: 0.5s; }
.animate-in:nth-child(6) { animation-delay: 0.6s; }

/* ── 模块标签页 ── */
.tabs {
  display: flex;
  gap: 4px;
  background: var(--border-light);
  padding: 4px;
  border-radius: var(--radius-full);
  width: fit-content;
  margin: 0 auto var(--space-xl);
  flex-wrap: wrap;
}

.tab-btn {
  padding: 10px 24px;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--duration-fast) var(--ease-out);
  white-space: nowrap;
}

.tab-btn.active {
  background: var(--surface);
  color: var(--primary-dark);
  box-shadow: var(--shadow-sm);
}

.tab-btn:hover:not(.active) {
  color: var(--text);
}

/* ── FAQ 折叠 ── */
.faq-list {
  max-width: 760px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  margin-bottom: var(--space-sm);
  background: var(--surface);
  overflow: hidden;
  transition: all var(--duration) var(--ease-out);
}

.faq-item:hover {
  border-color: var(--primary-light);
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  text-align: left;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  transition: color var(--duration-fast);
}

.faq-question:hover {
  color: var(--primary-dark);
}

.faq-question .faq-icon {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: var(--primary-dark);
  transition: transform var(--duration) var(--ease-out);
}

.faq-item.open .faq-question .faq-icon {
  transform: rotate(45deg);
  background: var(--primary);
  color: #fff;
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s var(--ease-out), padding 0.4s var(--ease-out);
}

.faq-item.open .faq-answer {
  max-height: 300px;
}

.faq-answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.8;
}

/* ── 时间轴 ── */
.timeline {
  position: relative;
  max-width: 700px;
  margin: 0 auto;
  padding-left: 32px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  padding-bottom: var(--space-lg);
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-dot {
  position: absolute;
  left: -26px;
  top: 4px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--primary);
  border: 3px solid var(--primary-light);
}

.timeline-dot.active {
  background: #5A8A62;
  border-color: #EDF4EE;
}

.timeline-dot.upcoming {
  background: var(--text-muted);
  border-color: var(--border-light);
}

.timeline-item h4 {
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 4px;
}

.timeline-item p {
  font-size: 14px;
  color: var(--text-secondary);
}

.timeline-date {
  display: inline-block;
  padding: 2px 10px;
  background: var(--primary-light);
  color: var(--primary-dark);
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 6px;
}

/* ── 下载卡片 ── */
.download-card {
  background: var(--surface);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  transition: all var(--duration) var(--ease-out);
}

.download-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.download-card .platform-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto var(--space-md);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 36px;
}

.download-card .platform-icon.android {
  background: #EDF4EE;
}

.download-card .platform-icon.ios {
  background: var(--primary-light);
}

.download-card h3 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
}

.download-card p {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
}

.badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--primary-light);
  color: var(--primary-dark);
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 600;
}

/* ── 响应式 ── */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(250,248,245,0.96);
    backdrop-filter: blur(20px);
    padding: var(--space-sm);
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-md);
    transform: translateY(-110%);
    opacity: 0;
    transition: all var(--duration) var(--ease-out);
    pointer-events: none;
  }
  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .nav-links a {
    width: 100%;
    padding: 12px 18px;
  }
  .nav-toggle {
    display: flex;
  }
  /* 手机端 footer：品牌区独占一行，链接两列排布 */
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
  }
  .footer-brand {
    grid-column: 1 / -1;
  }
  /* 「关注我们」目前都是占位链接，手机上暂时不显示 */
  .footer-grid > div:last-child {
    display: none;
  }
  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
  }
  .tabs {
    width: 100%;
    justify-content: center;
  }
  .section {
    padding: var(--space-xl) var(--space-sm);
  }
  .page-banner {
    padding: 120px var(--space-sm) 60px;
  }
}

@media (max-width: 480px) {
  .stat-grid {
    grid-template-columns: 1fr 1fr;
  }
  .download-grid {
    grid-template-columns: 1fr !important;
  }
  /* 窄屏进一步收紧留白 */
  .page-banner {
    padding: 104px var(--space-sm) 44px;
  }
  .section {
    padding: var(--space-lg) var(--space-sm);
  }
}