/* ==========================================================================
   净水实验室 — 全站样式表
   信息架构参考 Vacuum Wars，配色改为「水蓝」主题（净水品类更贴题）
   结构：1 变量 / 2 基础 / 3 顶部条 / 4 导航与巨型菜单 / 5 通用组件
        6 首页专属 / 7 榜单页专属 / 8 方法论页 / 9 响应式
   ========================================================================== */

/* ---------- 1. 设计变量 ---------- */
:root {
  --navy: #0b3a5c;          /* 导航条深蓝 */
  --blue-700: #075985;
  --blue-600: #0369a1;      /* 主色 */
  --blue-500: #0ea5e9;      /* 高亮 */
  --blue-200: #bae6fd;
  --blue-100: #e0f2fe;
  --blue-50: #f0f9ff;

  --accent: #dc2626;        /* 徽章红（BEST 标签） */
  --accent-dark: #b91c1c;
  --gold: #d97706;          /* 最佳综合 */
  --green: #16a34a;
  --green-50: #f0fdf4;

  --text: #1f2937;
  --text-2: #4b5563;
  --muted: #6b7280;
  --border: #e5e7eb;
  --bg: #ffffff;
  --bg-alt: #f8fafc;

  --radius: 10px;
  --radius-lg: 14px;
  --shadow: 0 1px 3px rgba(15, 23, 42, .08);
  --shadow-md: 0 6px 20px rgba(15, 23, 42, .10);
  --wrap: 1180px;
}

/* ---------- 2. 基础 ---------- */
* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
               "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--blue-600); text-decoration: none; }
a:hover { color: var(--blue-700); text-decoration: underline; }

h1, h2, h3, h4 { line-height: 1.35; margin: 0 0 .6em; font-weight: 700; color: #0f172a; }
h1 { font-size: 30px; }
h2 { font-size: 23px; }
h3 { font-size: 18px; }
p { margin: 0 0 1em; }

.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 20px; }

/* 章节标题（左侧竖条） */
.sec-title {
  font-size: 22px;
  font-weight: 700;
  padding-left: 13px;
  border-left: 4px solid var(--blue-500);
  margin: 0 0 6px;
  line-height: 1.3;
}
.sec-sub { color: var(--muted); font-size: 14px; margin: 0 0 20px; padding-left: 17px; }

/* 灰底 / 深色带（参考 Vacuum Wars 的分区手法） */
.band { background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); padding: 34px 0; }
.band-dark { background: #1f2937; color: #e5e7eb; padding: 30px 0; }
.band-dark h2 { color: #fff; }
.band-dark a { color: var(--blue-200); }

/* ---------- 3. 顶部提示条 ---------- */
.demo-bar {
  background: #fef3c7; color: #78350f; font-size: 13px;
  text-align: center; padding: 7px 16px; border-bottom: 1px solid #fde68a;
}
.demo-bar b { font-weight: 700; }

.disclosure-bar {
  background: var(--blue-50); color: var(--text-2);
  font-size: 12.5px; text-align: center; padding: 7px 16px;
  border-bottom: 1px solid var(--blue-100);
}
.disclosure-bar a { text-decoration: underline; }

/* ---------- 4. 导航与巨型菜单 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--navy);
  box-shadow: 0 2px 8px rgba(0, 0, 0, .15);
}
.header-inner {
  max-width: var(--wrap); margin: 0 auto; padding: 0 20px;
  display: flex; align-items: center; gap: 8px; height: 58px;
}

.brand { display: flex; align-items: center; gap: 9px; margin-right: 14px; flex: 0 0 auto; }
.brand:hover { text-decoration: none; }
.brand-mark { width: 30px; height: 30px; flex: 0 0 auto; }
.brand-text { color: #fff; font-size: 19px; font-weight: 800; letter-spacing: .5px; white-space: nowrap; }
.brand-text span { color: var(--blue-500); }

/* 主菜单 */
.nav { display: flex; align-items: center; gap: 2px; flex: 1; min-width: 0; }
.nav-item { position: relative; }
.nav-link {
  display: block; color: #dbeafe; font-size: 14px; font-weight: 500;
  padding: 18px 13px; white-space: nowrap; cursor: pointer;
  border-bottom: 3px solid transparent;
}
.nav-link:hover, .nav-item.open .nav-link {
  color: #fff; background: rgba(255, 255, 255, .08);
  border-bottom-color: var(--blue-500); text-decoration: none;
}
.nav-link .caret { font-size: 9px; opacity: .7; margin-left: 3px; }

/* 巨型菜单面板 */
.mega {
  display: none; position: absolute; top: 100%; left: 0;
  background: #fff; border: 1px solid var(--border); border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  box-shadow: var(--shadow-md); padding: 20px 22px; min-width: 560px; z-index: 120;
}
.nav-item.open .mega { display: flex; gap: 26px; }
.mega-col { min-width: 150px; }
.mega-col h4 {
  font-size: 12px; text-transform: uppercase; letter-spacing: .06em;
  color: var(--muted); margin: 0 0 9px; font-weight: 700;
}
.mega-col a { display: block; font-size: 13.5px; color: var(--text-2); padding: 3.5px 0; }
.mega-col a:hover { color: var(--blue-600); }
.mega-col a.hl { color: var(--blue-600); font-weight: 600; }

/* 搜索 */
.search-btn {
  background: none; border: 0; color: #dbeafe; cursor: pointer;
  padding: 8px; display: flex; align-items: center; flex: 0 0 auto;
}
.search-btn:hover { color: #fff; }
.menu-toggle { display: none; background: none; border: 0; color: #fff; font-size: 22px; cursor: pointer; padding: 4px 8px; }

/* ---------- 5. 通用组件 ---------- */
/* 徽章 */
.badge {
  display: inline-block; background: var(--accent); color: #fff;
  font-size: 11px; font-weight: 700; letter-spacing: .04em;
  padding: 3px 9px; border-radius: 4px; line-height: 1.5;
}
.badge.gold { background: var(--gold); }
.badge.green { background: var(--green); }
.badge.gray { background: #64748b; }

/* 评分 */
.score { font-weight: 800; color: var(--blue-600); }
.score-big { font-size: 26px; line-height: 1; }
.stars { color: #f59e0b; font-size: 14px; letter-spacing: 1px; }

/* 按钮 */
.btn {
  display: inline-block; padding: 10px 20px; border-radius: 8px;
  font-size: 14.5px; font-weight: 600; text-align: center; cursor: pointer;
  border: 1px solid transparent; transition: .15s;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--blue-600); color: #fff; }
.btn-primary:hover { background: var(--blue-700); color: #fff; }
.btn-buy { background: #ff9900; color: #111; font-weight: 700; }
.btn-buy:hover { background: #f08804; color: #111; }
.btn-ghost { background: #fff; border-color: var(--border); color: var(--text-2); }
.btn-ghost:hover { border-color: var(--blue-500); color: var(--blue-600); }
.btn-block { display: block; width: 100%; }

/* 卡片 */
.card {
  background: #fff; border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 18px;
}

/* 净水机 SVG 占位图 */
.prod-svg { width: 100%; height: auto; display: block; }

/* 真实产品图（官方商品图，本地 assets/products/） */
.prod-img { width: 100%; height: 100%; object-fit: contain; display: block; background: #fff; }
.pick .prod-img { width: 140px; height: 140px; margin: 10px auto; border-radius: 10px; }
.rank-prod .prod-img { width: 48px; height: 48px; flex: 0 0 auto; border: 1px solid var(--border); border-radius: 8px; padding: 3px; }
.review-head .thumb .prod-img { border-radius: 10px; }

/* 真实用户评价块（好评 / 差评 + 来源） */
.real-rev { border: 1px solid var(--border); border-radius: var(--radius); margin: 14px 0; overflow: hidden; }
.real-rev .rr-head {
  background: var(--blue-50); border-bottom: 1px solid var(--blue-100);
  padding: 9px 14px; font-size: 13.5px; font-weight: 700; color: var(--blue-700);
  display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap;
}
.real-rev .rr-head .src { font-weight: 400; font-size: 12px; color: var(--muted); }
.real-rev .rr-body { display: grid; grid-template-columns: 1fr 1fr; }
.real-rev .rr-col { padding: 11px 14px; font-size: 13.5px; }
.real-rev .rr-col.good { border-right: 1px solid var(--border); }
.real-rev .rr-col h5 { margin: 0 0 7px; font-size: 12.5px; letter-spacing: .02em; }
.real-rev .rr-col.good h5 { color: #15803d; }
.real-rev .rr-col.bad h5 { color: #b91c1c; }
.real-rev ul { margin: 0; padding-left: 17px; }
.real-rev li { margin-bottom: 5px; color: var(--text-2); }
.real-rev li em { font-style: normal; color: var(--muted); font-size: 12px; }

/* 数据来源说明 */
.src-note { font-size: 12.5px; color: var(--muted); margin: 10px 0 0; line-height: 1.7; }

/* 面包屑 */
.crumb { font-size: 13px; color: var(--muted); padding: 14px 0 0; }
.crumb a { color: var(--muted); }
.crumb span { margin: 0 6px; color: #cbd5e1; }

/* 评分条 */
.bar-row { display: flex; align-items: center; gap: 10px; font-size: 13px; margin-bottom: 6px; }
.bar-label { flex: 0 0 96px; color: var(--text-2); }
.bar-track { flex: 1; height: 7px; background: #eef2f6; border-radius: 4px; overflow: hidden; }
.bar-fill { height: 100%; background: linear-gradient(90deg, var(--blue-500), var(--blue-600)); border-radius: 4px; }
.bar-val { flex: 0 0 30px; text-align: right; font-weight: 600; color: var(--text-2); }

/* FAQ 手风琴 */
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 10px; overflow: hidden; }
.faq-q {
  width: 100%; text-align: left; background: #fff; border: 0; cursor: pointer;
  padding: 14px 16px; font-size: 15px; font-weight: 600; color: #0f172a;
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
  font-family: inherit;
}
.faq-q:hover { background: var(--bg-alt); }
.faq-q .ic { color: var(--blue-500); font-size: 18px; flex: 0 0 auto; transition: transform .2s; }
.faq-item.open .faq-q .ic { transform: rotate(45deg); }
.faq-a { display: none; padding: 0 16px 15px; color: var(--text-2); font-size: 14.5px; }
.faq-item.open .faq-a { display: block; }

/* 作者卡 */
.author-card {
  display: flex; gap: 16px; align-items: flex-start;
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 18px; background: #fff; max-width: 860px; margin: 0 auto;
}
.avatar {
  flex: 0 0 auto; width: 62px; height: 62px; border-radius: 50%;
  background: var(--blue-100); color: var(--blue-700);
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; font-weight: 700;
}
.author-card h4 { margin: 0 0 2px; font-size: 16px; }
.author-card .role { font-size: 12px; color: var(--muted); margin: 0 0 8px; }
.author-card p { font-size: 13.5px; color: var(--text-2); margin: 0 0 8px; }

/* ---------- 6. 首页专属 ---------- */
/* 主视觉 */
.hero { text-align: center; padding: 34px 0 10px; }
.hero h1 { font-size: 31px; margin-bottom: 4px; }
.hero .tagline { color: var(--muted); font-size: 15px; margin-bottom: 22px; }
.hero-logo { width: 108px; height: 108px; margin: 0 auto 6px; }

/* 品类卡 */
.cat-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: 12px; }
.cat-card {
  display: block; border: 1px solid var(--border); border-radius: var(--radius);
  background: #fff; padding: 12px 8px 14px; text-align: center; transition: .16s;
}
.cat-card:hover { border-color: var(--blue-500); box-shadow: var(--shadow-md); transform: translateY(-2px); text-decoration: none; }
.cat-card .badge { font-size: 10px; padding: 2px 7px; }
.cat-card h3 { font-size: 14.5px; margin: 9px 0 8px; color: #0f172a; line-height: 1.4; }
.cat-card .prod-svg { width: 62px; height: 62px; margin: 0 auto; }

/* 自营工具横幅 */
.promo-banner {
  display: flex; align-items: center; justify-content: center; gap: 26px;
  background: #0f172a; color: #fff; border-radius: var(--radius-lg);
  padding: 22px 26px; margin: 22px 0 0; flex-wrap: wrap;
}
.promo-banner .pt { font-size: 21px; font-weight: 800; margin: 0; line-height: 1.35; }
.promo-banner .ps { font-size: 13.5px; color: #94a3b8; margin: 4px 0 0; }
.promo-banner .btn { background: var(--accent); color: #fff; }

/* 列表流 */
.feed { display: grid; grid-template-columns: 1fr 300px; gap: 34px; align-items: start; }
.feed-item { padding-bottom: 15px; margin-bottom: 15px; border-bottom: 1px solid var(--border); }
.feed-item:last-child { border-bottom: 0; }
.feed-item h3 { font-size: 16.5px; margin: 0 0 4px; }
.feed-item h3 a { color: var(--blue-600); }
.feed-date { font-size: 12.5px; color: var(--muted); margin: 0 0 6px; }
.feed-item p { font-size: 14px; color: var(--text-2); margin: 0; }

/* 侧栏 */
.sidebar { position: sticky; top: 78px; }
.side-card { border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; margin-bottom: 18px; }
.side-card .sh { background: var(--navy); color: #fff; font-size: 13.5px; font-weight: 700; padding: 9px 14px; }
.side-card .sb { padding: 13px 14px; }
.side-card .sb a { display: block; font-size: 13.5px; padding: 4px 0; color: var(--text-2); }
.side-ad {
  background: linear-gradient(135deg, #0c4a6e, #0369a1); color: #fff;
  border-radius: var(--radius); padding: 20px 16px; text-align: center; margin-bottom: 18px;
}
.side-ad .t { font-size: 17px; font-weight: 800; margin: 0 0 6px; }
.side-ad .d { font-size: 12.5px; color: #bae6fd; margin: 0 0 12px; }

/* 内链云 */
.link-cloud { display: flex; flex-wrap: wrap; gap: 8px 16px; font-size: 14px; }

/* 视频墙 */
.video-wall { columns: 3; column-gap: 26px; font-size: 13.5px; }
.video-wall a { display: block; padding: 3px 0; color: var(--text-2); break-inside: avoid; }
.video-wall a::before { content: "▶"; color: var(--blue-500); font-size: 9px; margin-right: 6px; }
.video-wall a:hover { color: var(--blue-600); }

/* 媒体背书 */
.press { display: flex; align-items: center; justify-content: center; gap: 46px; flex-wrap: wrap; }
.press span { font-size: 20px; font-weight: 800; color: #64748b; letter-spacing: .04em; }

/* ---------- 7. 榜单页专属 ---------- */
/* Top Picks 三张卡 */
.picks { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-bottom: 30px; }
.pick {
  border: 1px solid var(--border); border-top: 4px solid var(--blue-500);
  border-radius: var(--radius-lg); padding: 16px; text-align: center; background: #fff;
}
.pick.p1 { border-top-color: var(--gold); }
.pick.p3 { border-top-color: var(--green); }
.pick .prod-svg { width: 96px; height: 96px; margin: 10px auto; }
.pick h3 { font-size: 16px; margin: 8px 0 4px; }
.pick .p-price { font-size: 20px; font-weight: 800; color: var(--accent); margin: 8px 0; }
.pick .p-price small { font-size: 12px; color: var(--muted); font-weight: 400; text-decoration: line-through; margin-left: 5px; }

/* 排行榜表格 */
.rank-table { width: 100%; border-collapse: collapse; font-size: 14px; background: #fff; }
.rank-table th {
  background: var(--navy); color: #fff; font-size: 13px; font-weight: 600;
  padding: 11px 12px; text-align: left; white-space: nowrap;
}
.rank-table td { padding: 12px; border-bottom: 1px solid var(--border); vertical-align: middle; }
.rank-table tr:hover td { background: var(--blue-50); }
.rank-no { font-size: 17px; font-weight: 800; color: var(--muted); text-align: center; width: 44px; }
.rank-no.top { color: var(--accent); }
.rank-prod { display: flex; align-items: center; gap: 11px; min-width: 210px; }
.rank-prod .prod-svg { width: 46px; height: 46px; flex: 0 0 auto; }
.rank-prod b { display: block; font-size: 14.5px; }
.rank-prod small { color: var(--muted); font-size: 12.5px; }

/* 逐款详评 */
.review {
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  padding: 20px; margin-bottom: 20px; background: #fff; scroll-margin-top: 76px;
}
.review-head { display: flex; gap: 18px; align-items: flex-start; margin-bottom: 14px; }
.review-head .thumb {
  flex: 0 0 auto; width: 118px; height: 118px; border-radius: var(--radius);
  background: var(--blue-50); border: 1px solid var(--blue-100);
  display: flex; align-items: center; justify-content: center;
}
.review-head .thumb .prod-svg { width: 88px; height: 88px; }
.review-head .meta { flex: 1; min-width: 0; }
.review-head h3 { font-size: 19px; margin: 6px 0 6px; }
.review-sum { font-size: 14.5px; color: var(--text-2); margin: 0 0 10px; }

/* 参数表 */
.spec-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--border); border: 1px solid var(--border);
  border-radius: var(--radius); overflow: hidden; margin: 14px 0;
}
.spec-grid div { background: #fff; padding: 9px 11px; }
.spec-grid .k { font-size: 12px; color: var(--muted); display: block; }
.spec-grid .v { font-size: 14px; font-weight: 600; color: #0f172a; }

/* 优缺点 */
.pros-cons { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 14px 0; }
.pros-cons > div { border-radius: var(--radius); padding: 12px 14px; font-size: 13.8px; }
.pros { background: var(--green-50); border: 1px solid #bbf7d0; }
.cons { background: #fef2f2; border: 1px solid #fecaca; }
.pros-cons h4 { font-size: 13px; margin: 0 0 7px; }
.pros h4 { color: #15803d; }
.cons h4 { color: #b91c1c; }
.pros-cons ul { margin: 0; padding-left: 18px; }
.pros-cons li { margin-bottom: 3px; }

/* 购买区 */
.buy-box {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  background: var(--bg-alt); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 13px 16px; flex-wrap: wrap;
}
.buy-box .price { font-size: 23px; font-weight: 800; color: var(--accent); line-height: 1.2; }
.buy-box .price small { display: block; font-size: 12px; color: var(--muted); font-weight: 400; }
.buy-box .stock { font-size: 12.5px; color: var(--green); font-weight: 600; }

/* 评分维度块 */
.score-block { background: var(--blue-50); border: 1px solid var(--blue-100); border-radius: var(--radius); padding: 13px 15px; margin: 14px 0; }
.score-block .sb-head { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 10px; }
.score-block .sb-head b { font-size: 15px; }

/* 更新信息 */
.upd { font-size: 13px; color: var(--muted); display: flex; gap: 16px; flex-wrap: wrap; align-items: center; margin-bottom: 18px; }
.chip { background: var(--blue-50); border: 1px solid var(--blue-100); color: var(--blue-700); font-size: 12px; padding: 2px 9px; border-radius: 20px; }

/* ---------- 8. 方法论页 ---------- */
.prose { max-width: 800px; }
.prose h2 { margin-top: 34px; }
.prose ul, .prose ol { padding-left: 22px; }
.prose li { margin-bottom: 7px; }
.step {
  display: flex; gap: 14px; margin-bottom: 16px;
  border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; background: #fff;
}
.step .n {
  flex: 0 0 auto; width: 30px; height: 30px; border-radius: 50%;
  background: var(--blue-600); color: #fff; font-weight: 700; font-size: 14px;
  display: flex; align-items: center; justify-content: center;
}
.step h4 { margin: 2px 0 4px; font-size: 15.5px; }
.step p { margin: 0; font-size: 14px; color: var(--text-2); }
.weight-table { width: 100%; border-collapse: collapse; font-size: 14px; margin: 14px 0; }
.weight-table th, .weight-table td { padding: 10px 12px; border-bottom: 1px solid var(--border); text-align: left; }
.weight-table th { background: var(--bg-alt); font-size: 13px; }
.weight-table td:last-child { text-align: right; font-weight: 700; color: var(--blue-600); }

/* ---------- 9. 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--border); background: var(--bg-alt);
  padding: 22px 0; margin-top: 40px;
  font-size: 13px; color: var(--muted);
}
.footer-inner { display: flex; justify-content: space-between; align-items: center; gap: 16px; flex-wrap: wrap; }
.footer-inner a { color: var(--muted); }

/* ---------- 10. 响应式 ---------- */
@media (max-width: 1080px) {
  .cat-grid { grid-template-columns: repeat(3, 1fr); }
  .feed { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .video-wall { columns: 2; }
  .mega { min-width: 420px; }
}

@media (max-width: 820px) {
  .menu-toggle { display: block; }
  .nav {
    display: none; position: absolute; top: 58px; left: 0; right: 0;
    background: var(--navy); flex-direction: column; align-items: stretch; gap: 0; padding: 6px 0;
    max-height: calc(100vh - 58px); overflow-y: auto;
  }
  .nav.open { display: flex; }
  .nav-link { padding: 13px 20px; border-bottom: 1px solid rgba(255, 255, 255, .08); }
  .mega {
    position: static; display: none; box-shadow: none; border: 0;
    border-radius: 0; background: rgba(255, 255, 255, .06); min-width: 0; padding: 10px 20px;
  }
  .nav-item.open .mega { display: block; }
  .mega-col h4 { color: #93c5fd; }
  .mega-col a { color: #dbeafe; }
  .header-inner { position: relative; }

  .hero h1 { font-size: 24px; }
  .cat-grid { grid-template-columns: repeat(2, 1fr); }
  .picks { grid-template-columns: 1fr; }
  .review-head { flex-direction: column; }
  .review-head .thumb { width: 100%; height: 130px; }
  .spec-grid { grid-template-columns: repeat(2, 1fr); }
  .pros-cons { grid-template-columns: 1fr; }
  .real-rev .rr-body { grid-template-columns: 1fr; }
  .real-rev .rr-col.good { border-right: 0; border-bottom: 1px solid var(--border); }
  .pick .prod-img { width: 120px; height: 120px; }
  .video-wall { columns: 1; }
  .rank-table { font-size: 13px; }
  .rank-table .hide-sm { display: none; }
  .press { gap: 24px; }
  .press span { font-size: 16px; }
  h1 { font-size: 24px; }
  h2 { font-size: 20px; }
}