/* ============================================
   Clash Verge Rev — c38
   青绿珊瑚渐变主题 · 开发者风格 · 卡片式布局
   ============================================ */

/* ===== CSS 变量系统 ===== */
:root {
  --primary: #14b8a6;
  --primary-dark: #0d9488;
  --primary-lighter: #ccfbf1;
  --secondary: #f97316;
  --accent: #8b5cf6;
  --gradient-start: #14b8a6;
  --gradient-end: #f97316;
  --bg: #f8fafc;
  --bg-card: #ffffff;
  --bg-tertiary: #f1f5f9;
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --border-light: #f1f5f9;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
  --shadow-glow: 0 0 40px rgba(20,184,166,0.15);
  --radius: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-full: 9999px;
  --transition: 0.25s ease;
  --transition-fast: 0.15s ease;

  /* 状态色 */
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", sans-serif;
  color: var(--text-primary);
  background: var(--bg);
  line-height: 1.7;
  font-size: 15px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}
a:hover { color: var(--primary-dark); }

img { max-width: 100%; height: auto; }

/* ===== 无障碍跳转链接 ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 9999;
  padding: 8px 16px;
  background: var(--primary);
  color: #fff;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 600;
  transition: top 0.3s;
}
.skip-link:focus {
  top: 16px;
}

/* ============================================
   Hero 区域（首页专用）
   ============================================ */
.hero-section {
  background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 60%, #9333ea 100%);
  position: relative;
  overflow: hidden;
  padding: 72px 24px 68px;
  text-align: center;
  color: #fff;
}
.hero-section::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 15% 45%, rgba(255,255,255,0.1) 0%, transparent 45%),
    radial-gradient(circle at 85% 35%, rgba(255,255,255,0.07) 0%, transparent 40%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(8px);
  padding: 5px 16px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 22px;
  letter-spacing: 0.03em;
  border: 1px solid rgba(255,255,255,0.2);
}
.hero-badge svg { width: 14px; height: 14px; }

.hero-title {
  font-size: clamp(32px, 6vw, 48px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}
.hero-subtitle {
  font-size: clamp(16px, 2.5vw, 19px);
  opacity: 0.9;
  font-weight: 400;
  line-height: 1.6;
  margin-bottom: 34px;
  max-width: 580px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}
.btn-hero-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: #fff;
  color: var(--primary-dark);
  font-weight: 700;
  font-size: 15px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  transition: all 0.25s ease;
  box-shadow: 0 4px 20px rgba(0,0,0,0.15);
  text-decoration: none;
}
.btn-hero-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.2);
  color: var(--primary-dark);
}
.btn-hero-primary svg { width: 18px; height: 18px; flex-shrink: 0; }

.btn-hero-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: rgba(255,255,255,0.12);
  color: #fff;
  font-weight: 600;
  font-size: 15px;
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,0.25);
  cursor: pointer;
  transition: all 0.25s ease;
  text-decoration: none;
  backdrop-filter: blur(4px);
}
.btn-hero-secondary:hover {
  background: rgba(255,255,255,0.2);
  transform: translateY(-2px);
  color: #fff;
}
.btn-hero-secondary svg { width: 18px; height: 18px; flex-shrink: 0; }

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 36px;
  margin-top: 44px;
  flex-wrap: wrap;
}
.hero-stat {
  text-align: center;
}
.hero-stat-num {
  font-size: 28px;
  font-weight: 800;
  display: block;
  line-height: 1.2;
}
.hero-stat-label {
  font-size: 12px;
  opacity: 0.72;
  margin-top: 2px;
  letter-spacing: 0.03em;
}

/* ============================================
   导航栏
   ============================================ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: box-shadow 0.3s;
}
.site-nav.scrolled {
  box-shadow: 0 2px 16px rgba(0,0,0,0.08);
}

.nav-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 4px;
  margin: 0;
  padding: 0;
}
.nav-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
  text-decoration: none;
}
.nav-link svg { width: 17px; height: 17px; flex-shrink: 0; }
.nav-link:hover {
  color: var(--primary);
  background: rgba(20,184,166,0.06);
}
.nav-link.active {
  color: var(--primary);
  background: rgba(20,184,166,0.1);
  font-weight: 600;
}

/* 汉堡菜单 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
  border-radius: 6px;
  transition: background 0.2s;
}
.menu-toggle:hover { background: rgba(0,0,0,0.05); }
.menu-toggle span {
  width: 20px; height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s;
}
.menu-toggle.open span:nth-child(1) { transform: rotate(45deg) translateY(7px) translateX(5px); }
.menu-toggle.open span:nth-child(2) { opacity: 0; }
.menu-toggle.open span:nth-child(3) { transform: rotate(-45deg) translateY(-7px) translateX(5px); }


/* ============================================
   主内容区
   ============================================ */
.main-content {
  flex: 1;
  max-width: 900px;
  width: 100%;
  margin: 0 auto;
  padding: 32px 24px 52px;
}

/* ============================================
   功能卡片（带左侧彩条）
   ============================================ */
.feature-section { margin-bottom: 26px; }

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 26px 28px;
  position: relative;
  overflow: hidden;
  transition: all 0.3s ease;
}
.feature-card::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--primary), var(--secondary));
  border-radius: 4px 0 0 4px;
  opacity: 0;
  transition: opacity 0.3s;
}
.feature-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateX(4px);
}
.feature-card:hover::before { opacity: 1; }

.feature-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}
.feature-icon {
  font-size: 24px;
  width: 42px; height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(20,184,166,0.1), rgba(249,115,22,0.1));
  border-radius: 10px;
  flex-shrink: 0;
}
.feature-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
}
.feature-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
  padding-left: 54px;
}
.feature-desc strong { color: var(--text-primary); }

/* ============================================
   SEO 关键词介绍区块
   ============================================ */
.seo-intro-section {
  margin-bottom: 38px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
}
.seo-intro-section .intro-lead {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 18px;
}
.seo-intro-section .intro-lead strong {
  color: var(--primary);
  font-weight: 700;
}
.seo-keyword-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  padding: 0;
  margin: 0;
}
.seo-keyword-tag {
  display: inline-block;
  padding: 5px 14px;
  background: linear-gradient(135deg, rgba(20,184,166,0.08), rgba(249,115,22,0.08));
  border: 1px solid rgba(20,184,166,0.15);
  border-radius: 20px;
  font-size: 13px;
  color: var(--primary-dark);
  font-weight: 500;
  transition: all 0.2s;
}
.seo-keyword-tag:hover {
  background: linear-gradient(135deg, rgba(20,184,166,0.15), rgba(249,115,22,0.15));
  border-color: var(--primary);
}

/* ============================================
   特性网格（多列卡片）
   ============================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin-bottom: 38px;
}
.feature-grid-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}
.feature-grid-card::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: scaleX(0);
  transition: transform 0.3s;
  transform-origin: left;
}
.feature-grid-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}
.feature-grid-card:hover::after { transform: scaleX(1); }

.fgc-icon {
  font-size: 28px;
  margin-bottom: 12px;
}
.fgc-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
}
.fgc-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ============================================
   编号列表（about 页面特性列表）
   ============================================ */
.section-heading {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 20px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-heading::before {
  content: '';
  width: 4px; height: 20px;
  background: linear-gradient(180deg, var(--primary), var(--secondary));
  border-radius: 2px;
}

.info-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.info-item {
  display: flex;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  transition: all 0.25s;
}
.info-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: rgba(20,184,166,0.25);
}
.info-num {
  width: 32px; height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-weight: 800;
  font-size: 14px;
  border-radius: 8px;
  flex-shrink: 0;
  margin-top: 2px;
}
.info-content h4 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 4px;
}
.info-content p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ============================================
   致谢卡片
   ============================================ */
.credit-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 22px;
  margin-bottom: 12px;
  transition: all 0.25s;
}
.credit-card:hover {
  box-shadow: var(--shadow-sm);
  border-color: rgba(20,184,166,0.2);
}
.credit-name {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 4px;
}
.credit-name a { color: var(--primary); }
.credit-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================
   许可证框
   ============================================ */
.license-box {
  background: var(--bg-card);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
}
.license-icon { font-size: 32px; margin-bottom: 8px; }
.license-type {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}
.license-note {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.65;
}


/* ===== 多节点下载网格 ===== */
.dl-nodes-section {
  margin-bottom: 38px;
}
.dl-nodes-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
}
.dl-nodes-header h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
}
.dl-nodes-count {
  font-size: 12px;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  background: var(--primary-lighter);
  color: var(--primary-dark);
  font-weight: 600;
}
.dl-nodes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
}
.dl-node {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 18px;
  transition: all var(--transition);
  text-decoration: none !important;
  color: inherit;
}
.dl-node:hover {
  border-color: rgba(20,184,166,0.4);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.dl-node-icon {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}
.dl-node-info {
  flex: 1;
  min-width: 0;
}
.dl-node-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 2px;
}
.dl-node-desc {
  font-size: 12px;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.dl-node-speed {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 11px;
  padding: 1px 7px;
  border-radius: var(--radius-full);
  font-weight: 600;
  margin-left: 6px;
  vertical-align: middle;
}
.speed-fast { background: #ecfdf5; color: #065f46; }
.speed-mid { background: #fffbeb; color: #92400e; }
.speed-slow { background: #eff6ff; color: #1e40af; }
.dl-node-go {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-size: 14px;
  transition: all var(--transition);
}
.dl-node:hover .dl-node-go {
  transform: scale(1.1);
  box-shadow: 0 2px 8px rgba(20,184,166,0.35);
}

/* 节点标签（官方/镜像/社区） */
.node-tag {
  display: inline-block;
  font-size: 10px;
  padding: 1px 6px;
  border-radius: 4px;
  font-weight: 600;
  letter-spacing: 0.02em;
  vertical-align: middle;
}
.node-official { background: #dbeafe; color: #1d4ed8; }
.node-mirror { background: #f3e8ff; color: #7c3aed; }
.node-community { background: #ecfdf5; color: #059669; }

/* ===== 首页快捷下载节点横条 ===== */
.quick-dl-bar {
  background: linear-gradient(135deg, rgba(20,184,166,0.06), rgba(249,115,22,0.08));
  border: 1px solid rgba(20,184,166,0.15);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  margin-bottom: 38px;
}
.quick-dl-bar h3 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}
.quick-dl-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.quick-dl-item {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 7px 14px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none !important;
  transition: all var(--transition-fast);
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-secondary);
}
.quick-dl-item:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(20,184,166,0.04);
  transform: translateY(-1px);
}
.quick-dl-item svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

@media (max-width: 640px) {
  .dl-nodes-grid { grid-template-columns: 1fr; }
  .quick-dl-list { flex-direction: column; }
  .quick-dl-item { justify-content: center; }
}

/* 平台下载区 */
.download-platform {
  margin-bottom: 32px;
  scroll-margin-top: 70px;
}
.platform-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-light);
}
.platform-icon {
  font-size: 28px;
  width: 46px; height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
}
.platform-icon.macos { background: rgba(0,0,0,0.04); }
.platform-icon.linux { background: rgba(0,0,0,0.04); }
.platform-icon.windows { background: rgba(0,120,215,0.08); }
.platform-name {
  font-size: 20px;
  font-weight: 750;
  flex: 1;
}
.platform-badge {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  background: rgba(20,184,166,0.1);
  color: var(--primary);
  border-radius: 12px;
  letter-spacing: 0.02em;
}

.download-files { display: flex; flex-direction: column; gap: 8px; }

.download-file-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
  transition: all 0.2s;
}
.download-file-row:hover {
  border-color: rgba(20,184,166,0.3);
  box-shadow: var(--shadow-sm);
}
.file-info { display: flex; align-items: center; gap: 12px; }
.file-icon { font-size: 22px; flex-shrink: 0; }
.file-details h4 {
  font-size: 14px;
  font-weight: 650;
  margin-bottom: 2px;
}
.file-details p {
  font-size: 12px;
  color: var(--text-muted);
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.25s;
  white-space: nowrap;
  text-decoration: none;
}
.btn-download svg { width: 14px; height: 14px; flex-shrink: 0; }
.btn-download:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(20,184,166,0.3);
  color: #fff;
}

/* 平台标签导航 */
.platform-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 26px;
  flex-wrap: wrap;
  justify-content: center;
}
.platform-tab {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 22px;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 600;
  color: var(--text-secondary);
  background: var(--bg-card);
  cursor: pointer;
  transition: all 0.25s;
  text-decoration: none;
}
.platform-tab:hover,
.platform-tab.active {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(20,184,166,0.04);
}
.platform-tab .tab-icon { font-size: 18px; }

/* 安装指南 */
.guide-steps {
  margin-top: 32px;
}
.guide-step {
  display: flex;
  gap: 16px;
  margin-bottom: 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px;
  transition: all 0.25s;
}
.guide-step:hover { box-shadow: var(--shadow-sm); }
.step-num {
  width: 36px; height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-weight: 800;
  font-size: 15px;
  border-radius: 50%;
  flex-shrink: 0;
}
.step-content h4 { font-size: 15px; font-weight: 700; margin-bottom: 4px; }
.step-content p { font-size: 13px; color: var(--text-secondary); line-height: 1.65; }
.step-content code {
  background: rgba(20,184,166,0.08);
  color: var(--primary-dark);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 12px;
  font-family: "Cascadia Code", "Fira Code", Consolas, monospace;
}

/* 版本对比表 */
.version-table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.version-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  min-width: 550px;
}
.version-table th {
  background: linear-gradient(135deg, rgba(20,184,166,0.06), rgba(249,115,22,0.06));
  padding: 12px 16px;
  text-align: left;
  font-weight: 700;
  font-size: 13px;
  color: var(--text-primary);
  white-space: nowrap;
  border-bottom: 2px solid var(--border);
}
.version-table td {
  padding: 11px 16px;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-secondary);
}
.version-table tr:last-child td { border-bottom: none; }
.version-table tr:hover td { background: rgba(20,184,166,0.02); }
.version-table .check { color: var(--success); font-weight: 700; }
.version-table .cross { color: var(--text-muted); }
.version-table .warn { color: var(--warning); font-weight: 600; font-size: 12px; }

/* ============================================
   FAQ 手风琴
   ============================================ */
.faq-section { margin-bottom: 38px; }
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 10px;
  overflow: hidden;
  transition: all 0.25s;
}
.faq-item:hover { border-color: rgba(20,184,166,0.2); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 18px 22px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 15px;
  font-weight: 650;
  color: var(--text-primary);
  text-align: left;
  transition: all 0.2s;
  font-family: inherit;
}
.faq-question:hover { color: var(--primary); }
.faq-q-icon {
  font-size: 18px;
  flex-shrink: 0;
  transition: transform 0.3s;
  margin-left: 12px;
  color: var(--text-muted);
}
.faq-item.open .faq-q-icon { transform: rotate(45deg); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}
.faq-answer-inner {
  padding: 0 22px 18px;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.75;
}
.faq-answer-inner strong { color: var(--text-primary); }
.faq-answer-inner a { color: var(--primary); font-weight: 500; }
.faq-item.open .faq-answer { max-height: 1000px; }

/* ===== FAQ 原生手风琴共享样式（details/summary） ===== */
.faq-section { margin-bottom: 32px; }

.faq-category {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.faq-category::before {
  content: '';
  display: block;
  width: 20px;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
}

.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-list .faq-item { margin-bottom: 0; }

.faq-item[open] {
  border-color: var(--primary);
}
.faq-item[open] .faq-q {
  color: var(--primary);
  background: rgba(102,126,234,0.04);
}

.faq-q {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 20px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  cursor: pointer;
  list-style: none;
  transition: background var(--transition), color var(--transition);
  user-select: none;
}
.faq-q::-webkit-details-marker { display: none; }
.faq-q::before {
  content: 'Q';
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #fff;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.faq-item[open] .faq-q::before {
  background: var(--primary);
}
.faq-q:hover { background: var(--border-light); }

.faq-a {
  padding: 0 20px 18px 54px;
  font-size: 14.5px;
  color: var(--text-secondary);
  line-height: 1.8;
  border-top: 1px solid var(--border-light);
}
.faq-a strong { color: var(--text-primary); font-weight: 600; }
.faq-a code {
  background: var(--border-light);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 13px;
  font-family: 'SF Mono', Consolas, monospace;
  color: var(--primary-dark);
}
.faq-a a { color: var(--primary); font-weight: 500; }
.faq-a a:hover { text-decoration: underline; }

/* ============================================
   友情链接区域
   ============================================ */
.friend-links-section { margin-top: 44px; }
.friend-links-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-primary);
}
.friend-links-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.friend-links-grid a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 13px;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}
.friend-links-grid a:hover {
  color: var(--primary);
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
  transform: translateY(-1px);
}
.friend-links-grid a span {
  width: 6px; height: 6px;
  background: var(--primary);
  border-radius: 50%;
  flex-shrink: 0;
}

/* ============================================
   提示框（notice-box）
   ============================================ */
.notice-box {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  background: rgba(20,184,166,0.05);
  border: 1px solid rgba(20,184,166,0.18);
  border-radius: var(--radius);
  padding: 16px 20px;
}
.notice-icon {
  font-size: 18px;
  line-height: 1.5;
  flex-shrink: 0;
}
.notice-text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}
.notice-text strong { color: var(--text-primary); }

/* ============================================
   页脚
   ============================================ */
.site-footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 32px 24px;
  text-align: center;
  margin-top: auto;
}
.footer-platforms {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.footer-platforms span {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
}
.footer-copyright {
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.7;
}

/* ============================================
   滚动显示动画
   ============================================ */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.55s ease-out, transform 0.55s ease-out;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 尊重用户的减少动效偏好（无障碍） */
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; }
}

/* ============================================
   下载弹窗
   ============================================ */
.popup-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.45);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 9999;
  justify-content: center;
  align-items: center;
}
.popup-overlay.active {
  display: flex;
}
.popup {
  background: #fff;
  border-radius: 16px;
  padding: 40px 32px 32px;
  max-width: 380px;
  width: 90%;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0,0,0,.15);
  animation: popupIn .25s ease;
}
@keyframes popupIn {
  from { opacity: 0; transform: translateY(12px) scale(.96); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}
.popup-ic { font-size: 40px; margin-bottom: 12px; }
.popup h3 {
  font-size: 20px; font-weight: 700;
  margin: 0 0 8px; color: var(--text-primary);
}
.popup p {
  font-size: 14px; color: var(--text-secondary);
  margin: 0 0 24px;
}
.popup-btns { display: flex; gap: 12px; justify-content: center; }
.btn-popup {
  padding: 10px 24px; border-radius: var(--radius);
  font-size: 14px; font-weight: 600; cursor: pointer;
  border: none; transition: all 0.25s ease; font-family: inherit;
}
.btn-cancel {
  background: var(--bg-tertiary, #f1f5f9);
  color: var(--text-secondary);
}
.btn-cancel:hover { background: var(--border); }
.btn-confirm {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  box-shadow: 0 4px 12px rgba(20,184,166,.3);
}
.btn-confirm:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(20,184,166,.4);
}

/* ============================================
   响应式设计
   ============================================ */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    flex-direction: column;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    gap: 2px;
    z-index: 99;
  }
  .nav-links.open { display: flex; }
  .nav-link {
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 15px;
  }
  .menu-toggle { display: flex; }

  .hero-section { padding: 48px 20px 44px; }
  .hero-stats { gap: 24px; }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .feature-desc { padding-left: 0; padding-top: 8px; }
  .feature-header { flex-wrap: wrap; }

  .download-file-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  .btn-download { width: 100%; justify-content: center; }

  .platform-tabs { flex-direction: column; }
  .platform-tab { justify-content: center; }

  .main-content { padding: 20px 16px 40px; }

  .info-item { flex-direction: column; gap: 10px; }

  .friend-links-grid { gap: 6px; }
  .friend-links-grid a { font-size: 12px; padding: 6px 12px; }

  /* ===== 子页面组件移动端适配 ===== */

  /* tutorial: step-card grid 变单列 */
  .step-card {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 20px;
  }
  .step-number { width: 44px; height: 44px; font-size: 18px; }

  /* features: proto-grid 单列 */
  .proto-grid { grid-template-columns: 1fr; }

  /* faq: toc-list 垂直排列 */
  .faq-toc-list { flex-direction: column; }
  .faq-toc-list a { display: block; }

  /* comparison: client-cards 单列 */
  .client-cards { grid-template-columns: 1fr; }

  /* download: dl-nodes-grid 单列 */
  .dl-nodes-grid { grid-template-columns: 1fr; }

  /* changelog: sections 单列 */
  .changelog-sections { grid-template-columns: 1fr; }
  .section-sep { grid-template-columns: 1fr; }

  /* privacy/terms: policy-content 缩小 padding */
  .policy-content { padding: 24px 20px; }
  .toc-sticky { padding: 16px 18px; }

  /* comparison: verdict-box 缩小 */
  .verdict-box { padding: 20px 18px; }
  .verdict-title { font-size: 17px; }
}
}

@media (max-width: 480px) {
  .hero-title { font-size: 26px; }
  .hero-subtitle { font-size: 15px; }
  .hero-buttons { flex-direction: column; align-items: stretch; }
  .btn-hero-primary, .btn-hero-secondary { justify-content: center; }

  .feature-card { padding: 20px; }

  .site-title { font-size: 19px; }
}

/* ===== Footer Legal Links ===== */
.footer-legal {
  display: flex; justify-content: center; align-items: center; gap: 10px;
  margin-top: 14px; flex-wrap: wrap;
}
.footer-legal a {
  font-size: 12px; color: var(--text-muted);
  text-decoration: none; transition: color var(--transition);
}
.footer-legal a:hover { color: var(--primary); }
.footer-legal span { font-size: 12px; color: var(--border-color); }

/* ===== 通用间距类 ===== */
.mb-38 { margin-bottom: 38px; }
.mb-26 { margin-bottom: 26px; }
.mb-20 { margin-bottom: 20px; }
.mb-18 { margin-bottom: 18px; }
.mb-16 { margin-bottom: 16px; }
.mb-12 { margin-bottom: 12px; }
.mt-36 { margin-top: 36px; }

/* ============================================
   Policy / Terms 页通用样式
   ============================================ */
.policy-content {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px 44px;
  max-width: 760px;
}
.policy-content h2 {
  font-size: 18px; font-weight: 700;
  color: var(--text-primary);
  margin: 32px 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-light);
}
.policy-content h2:first-child { margin-top: 0; }
.policy-content p {
  font-size: 14px; color: var(--text-secondary);
  line-height: 1.85; margin-bottom: 12px;
}
.policy-content p:last-child { margin-bottom: 0; }
.policy-content strong { color: var(--text-primary); font-weight: 600; }
.policy-content ul, .policy-content ol {
  padding-left: 22px;
  margin-bottom: 12px;
}
.policy-content li {
  font-size: 14px; color: var(--text-secondary);
  line-height: 1.85; margin-bottom: 6px;
}
.policy-content code {
  background: var(--border-light);
  padding: 1px 6px; border-radius: 4px;
  font-size: 12.5px; font-family: 'SF Mono', Consolas, monospace;
}
.policy-date {
  font-size: 12px; color: var(--text-muted);
  margin-top: 6px;
}
.policy-badge {
  display: inline-flex; align-items: center; gap: 6px;
  background: rgba(5,150,105,0.08);
  border: 1px solid rgba(5,150,105,0.2);
  border-radius: var(--radius);
  padding: 8px 16px; font-size: 13px; font-weight: 600;
  color: #059669; margin-bottom: 24px;
}
.toc-sticky {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px 24px;
  margin-bottom: 28px;
}
.toc-sticky-title {
  font-size: 13px; font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase; letter-spacing: 0.5px;
  margin-bottom: 12px;
}
.toc-sticky-list { list-style: none; padding: 0; margin: 0; }
.toc-sticky-list li { margin-bottom: 6px; }
.toc-sticky-list a {
  font-size: 13.5px; color: var(--primary);
  text-decoration: none; font-weight: 500;
}
.toc-sticky-list a:hover { text-decoration: underline; }

/* Terms 页专用：免责声明框 */
.disclaimer-box {
  background: rgba(239,68,68,0.04);
  border: 1px solid rgba(239,68,68,0.15);
  border-radius: var(--radius-lg);
  padding: 20px 24px;
  margin-bottom: 28px;
}
.disclaimer-box .db-title {
  font-size: 14px; font-weight: 700;
  color: #dc2626; margin-bottom: 8px;
  display: flex; align-items: center; gap: 8px;
}
.disclaimer-box p {
  font-size: 13.5px; color: var(--text-secondary);
  line-height: 1.8; margin: 0;
}