/* 51吃瓜：暗色资讯聚合风。核心正文与布局不依赖外部框架。 */
:root {
    --brand: #C84A5A;
    --copper: #D08A48;
    --ink: #121214;
    --bg: #17171A;
    --panel: #222226;
    --text: #F1EEEE;
    --muted: #A9A3A6;
    --accent: #E59A3A;
    --line: rgba(255,255,255,.10);
    --line-strong: rgba(255,255,255,.18);
    --shadow: 0 22px 60px rgba(0,0,0,.28);
    --radius: 22px;
    --shell: 1180px;
    --reading: 820px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif; line-height: 1.72; text-rendering: optimizeLegibility; }
body.modal-open { overflow: hidden; }
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
a:hover { color: #fff; }
button, input { font: inherit; }
button { cursor: pointer; }
.shell { width: min(calc(100% - 48px), var(--shell)); margin-inline: auto; }
.narrow { width: min(calc(100% - 48px), var(--reading)); margin-inline: auto; }
.skip-link { position: fixed; z-index: 1000; left: 16px; top: 12px; transform: translateY(-140%); background: var(--accent); color: #151515; padding: 10px 14px; border-radius: 10px; font-weight: 800; }
.skip-link:focus { transform: translateY(0); }
.site-header { position: sticky; top: 0; z-index: 80; background: rgba(18,18,20,.92); border-bottom: 1px solid var(--line); backdrop-filter: blur(14px); }
.header-inner { min-height: 78px; display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 24px; }
.brand-mark { display: inline-flex; align-items: center; gap: 12px; min-width: max-content; }
.brand-mark img { width: 46px; height: 46px; border-radius: 14px; object-fit: cover; background: var(--panel); }
.brand-copy { display: grid; line-height: 1.2; }
.brand-copy strong { font-size: 1.06rem; letter-spacing: .04em; }
.brand-copy small { color: var(--muted); margin-top: 5px; font-size: .75rem; }
.primary-nav { display: flex; justify-content: center; align-items: center; gap: 4px; }
.primary-nav a { color: #c8c3c5; padding: 9px 12px; border-radius: 10px; font-size: .93rem; transition: .2s ease; }
.primary-nav a:hover, .primary-nav a[aria-current="page"] { color: var(--text); background: rgba(255,255,255,.07); }
.search-open, .menu-toggle { border: 1px solid var(--line-strong); background: transparent; color: var(--text); border-radius: 12px; padding: 9px 13px; }
.search-open:hover, .menu-toggle:hover { border-color: rgba(229,154,58,.65); }
.menu-toggle { display: none; }
.search-modal[hidden] { display: none !important; }
.search-modal { position: fixed; inset: 0; z-index: 200; display: grid; place-items: center; padding: 22px; background: rgba(5,5,7,.78); }
.search-dialog { width: min(620px, 100%); background: #202024; border: 1px solid var(--line-strong); border-radius: 24px; box-shadow: var(--shadow); padding: 34px; position: relative; }
.search-dialog h2 { margin: 6px 0 8px; font-size: clamp(1.7rem, 4vw, 2.6rem); }
.search-dialog p { color: var(--muted); }
.search-close { position: absolute; right: 18px; top: 18px; border: 0; background: #2a2a2f; color: var(--text); border-radius: 10px; padding: 8px 10px; }
.search-form label, .inline-search label { display: block; margin-bottom: 8px; font-weight: 700; }
.search-row { display: grid; grid-template-columns: 1fr auto; gap: 10px; }
.search-row input { min-width: 0; width: 100%; background: #151518; border: 1px solid var(--line-strong); color: var(--text); border-radius: 12px; padding: 13px 14px; outline: none; }
.search-row input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(229,154,58,.12); }
.search-row button { border: 0; background: var(--accent); color: #171310; font-weight: 800; border-radius: 12px; padding: 0 18px; }
.breadcrumbs { width: min(calc(100% - 48px), var(--shell)); margin: 22px auto 0; }
.breadcrumbs ol { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; color: var(--muted); font-size: .86rem; }
.breadcrumbs li:not(:last-child)::after { content: "/"; margin-left: 8px; color: #676267; }
.breadcrumbs a:hover { color: var(--accent); }
main { overflow: hidden; }
.hero { padding: 58px 0 36px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(340px, .95fr); gap: 60px; align-items: center; }
.eyebrow, .section-kicker { margin: 0 0 10px; color: #e1a465; font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .12em; }
.hero h1, .page-hero h1, .not-found h1 { margin: 0; line-height: 1.08; letter-spacing: -.035em; font-size: clamp(2.6rem, 6vw, 5rem); }
.hero-lead { max-width: 760px; color: #c8c3c5; font-size: clamp(1.02rem, 1.6vw, 1.22rem); margin: 24px 0 0; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 0 18px; border-radius: 13px; font-weight: 800; transition: transform .18s ease, border-color .18s ease, background .18s ease; }
.button:hover { transform: translateY(-1px); }
.button.primary { background: var(--brand); color: #fff; }
.button.secondary { background: var(--accent); color: #20170f; }
.button.ghost { border: 1px solid var(--line-strong); color: var(--text); }
.identity-list { margin: 38px 0 0; padding-top: 24px; border-top: 1px solid var(--line); display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.identity-list div { min-width: 0; }
.identity-list dt { color: var(--muted); font-size: .78rem; }
.identity-list dd { margin: 6px 0 0; font-weight: 800; overflow-wrap: anywhere; }
.hero-visual { margin: 0; position: relative; }
.hero-visual img { width: 100%; aspect-ratio: 1.22; object-fit: cover; border-radius: 30px 8px 30px 8px; border: 1px solid var(--line); background: var(--panel); box-shadow: var(--shadow); }
.hero-visual::after { content: ""; position: absolute; inset: auto 26px 52px auto; width: 84px; height: 84px; border-radius: 50%; border: 1px solid rgba(229,154,58,.35); pointer-events: none; }
.hero-visual figcaption { color: var(--muted); font-size: .83rem; margin-top: 12px; }
.section { padding: 86px 0; border-top: 1px solid rgba(255,255,255,.04); }
.section-compact { padding: 58px 0 46px; }
.section-muted { background: #141416; }
.reading-intro h2, .section-heading h2, .media-note-copy h2, .two-column-grid h2, .final-callout h2, .privacy-stack h2, .safety-grid h2, .prose h2 { margin: 0; line-height: 1.18; letter-spacing: -.02em; font-size: clamp(1.9rem, 4vw, 3.2rem); }
.reading-intro p:last-child { color: #c8c3c5; font-size: 1.08rem; }
.section-heading { margin-bottom: 30px; }
.split-heading { display: grid; grid-template-columns: 1.2fr .8fr; gap: 44px; align-items: end; }
.split-heading > p { margin: 0; color: var(--muted); }
.flow-list { display: grid; border-top: 1px solid var(--line); }
.flow-item { display: grid; grid-template-columns: 80px 1fr; gap: 28px; padding: 28px 0; border-bottom: 1px solid var(--line); }
.flow-number { color: var(--brand); font-size: 1.2rem; font-weight: 900; letter-spacing: .08em; }
.flow-item h3 { margin: 0 0 8px; font-size: 1.35rem; }
.flow-item p { margin: 0 0 10px; color: #bdb7ba; max-width: 820px; }
.text-link { display: inline-flex; color: #f0b369; font-weight: 800; }
.text-link::after { content: "→"; margin-left: 7px; transition: transform .18s ease; }
.text-link:hover::after { transform: translateX(3px); }
.media-note-grid { display: grid; grid-template-columns: minmax(300px, .92fr) minmax(0, 1.08fr); gap: 56px; align-items: center; }
.media-note-grid.reverse figure { order: 2; }
.media-note-grid figure { margin: 0; }
.media-note-grid img, .two-column-grid img, .app-strip img, .final-callout img { width: 100%; border-radius: var(--radius); border: 1px solid var(--line); background: var(--panel); object-fit: cover; }
.media-note-copy p { color: #c4bec1; }
.check-list { list-style: none; margin: 24px 0; padding: 0; display: grid; gap: 10px; }
.check-list li { position: relative; padding-left: 25px; color: #d5d0d2; }
.check-list li::before { content: ""; position: absolute; width: 8px; height: 8px; left: 0; top: .64em; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 4px rgba(229,154,58,.12); }
.check-list.large { gap: 16px; }
.app-strip { display: grid; grid-template-columns: 1.1fr .9fr; gap: 52px; align-items: center; }
.app-strip-copy h2 { margin: 0; font-size: clamp(2rem, 4.2vw, 3.3rem); line-height: 1.16; }
.app-strip-copy p { color: #bdb7ba; max-width: 760px; }
.app-strip-image { margin: 0; }
.inline-links { display: flex; flex-wrap: wrap; gap: 10px 20px; margin-top: 22px; }
.inline-links a { color: #edb16d; font-weight: 800; border-bottom: 1px solid rgba(237,177,109,.3); }
.two-column-grid { display: grid; grid-template-columns: 1fr .82fr; gap: 60px; align-items: start; }
.two-column-grid p { color: #c6c0c2; }
.editor-note { border-left: 3px solid var(--brand); padding: 4px 0 4px 26px; color: #d3ced0; }
.editor-note span { display: inline-block; color: #e0a567; font-size: .8rem; font-weight: 900; letter-spacing: .1em; text-transform: uppercase; }
.editor-note p { font-size: 1.08rem; }
.index-list { border-top: 1px solid var(--line); }
.index-list a { display: grid; grid-template-columns: 170px 1fr; gap: 26px; padding: 20px 0; border-bottom: 1px solid var(--line); }
.index-list a span { color: var(--muted); }
.index-list a strong { font-size: 1.08rem; }
.index-list a:hover strong { color: var(--accent); }
.index-list.short { margin-top: 34px; }
.final-callout-inner { display: grid; grid-template-columns: .8fr 1.2fr; gap: 52px; align-items: center; padding: 38px; background: linear-gradient(135deg, rgba(200,74,90,.14), rgba(208,138,72,.08)); border: 1px solid rgba(200,74,90,.28); border-radius: 28px; }
.final-callout p:not(.section-kicker) { color: #c9c3c5; }
.page-hero { padding: 62px 0 50px; }
.page-hero-grid { display: grid; grid-template-columns: 1fr 400px; gap: 54px; align-items: center; }
.page-hero h1 { font-size: clamp(2.35rem, 5.2vw, 4.6rem); }
.page-hero p { color: #c7c1c3; font-size: 1.08rem; }
.page-hero figure { margin: 0; }
.page-hero img { width: 100%; aspect-ratio: 1.4; object-fit: cover; border-radius: 24px; border: 1px solid var(--line); background: var(--panel); }
.guide-hero { padding-bottom: 28px; }
.lead-narrow { max-width: 780px; }
.timeline { position: relative; }
.timeline::before { content: ""; position: absolute; left: 35px; top: 10px; bottom: 10px; width: 1px; background: linear-gradient(var(--brand), rgba(208,138,72,.18)); }
.timeline-item { position: relative; display: grid; grid-template-columns: 72px 1fr; gap: 28px; padding: 0 0 46px; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-number { position: relative; z-index: 2; width: 72px; height: 72px; display: grid; place-items: center; border-radius: 50%; background: #1e1e22; border: 1px solid rgba(200,74,90,.42); color: #e27986; font-weight: 900; }
.timeline-item h2 { margin: 4px 0 8px; font-size: clamp(1.55rem, 3.2vw, 2.45rem); }
.timeline-item p { margin: 0; color: #bbb5b8; max-width: 850px; }
.notice { margin: 26px 0 0; padding: 18px 20px; border-radius: 14px; border: 1px solid var(--line); background: rgba(255,255,255,.03); }
.notice strong { display: block; margin-bottom: 5px; }
.notice p { margin: 0; color: #c7c1c3; }
.notice-warm { border-color: rgba(229,154,58,.35); background: rgba(229,154,58,.06); }
.notice-alert { border-color: rgba(200,74,90,.45); background: rgba(200,74,90,.07); }
.article-stack { border-top: 1px solid var(--line); }
.article-stack article { display: grid; grid-template-columns: 64px 1fr; gap: 26px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.article-stack article > span { color: var(--brand); font-weight: 900; }
.article-stack h3 { margin: 0 0 7px; font-size: 1.32rem; }
.article-stack p { margin: 0; color: #beb8bb; }
.note-grid, .rule-grid, .safety-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.note-grid article, .rule-grid article, .safety-grid article { padding: 24px; border: 1px solid var(--line); background: #1d1d21; border-radius: 16px; }
.note-grid h3, .rule-grid h3 { margin: 0 0 8px; font-size: 1.25rem; }
.note-grid p, .rule-grid p, .safety-grid p { margin: 0; color: #bcb6b9; }
.numbered-list { margin: 26px 0 0; padding-left: 1.4rem; display: grid; gap: 15px; color: #c7c1c3; }
.numbered-list a { color: #edb16d; text-decoration: underline; text-decoration-color: rgba(237,177,109,.35); text-underline-offset: 3px; }
.article-hero { padding-bottom: 32px; }
.article-hero .narrow { margin-inline: auto; }
.rule-grid { grid-template-columns: repeat(5, 1fr); gap: 10px; }
.rule-grid article { min-height: 245px; padding: 22px 18px; }
.rule-grid h3 { font-size: 1.05rem; }
.faq-list { display: grid; gap: 10px; }
.faq-item { border: 1px solid var(--line); background: #1e1e22; border-radius: 14px; overflow: hidden; }
.faq-item summary { list-style: none; display: flex; justify-content: space-between; gap: 22px; padding: 19px 21px; cursor: pointer; font-weight: 800; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary span { color: var(--accent); }
.faq-item[open] summary span { transform: rotate(45deg); }
.faq-answer { padding: 0 21px 20px; color: #bbb5b8; }
.faq-answer p { margin: 0; }
.inline-search { margin-top: 24px; }
.prose h2 { margin-top: 38px; font-size: clamp(1.6rem, 3vw, 2.3rem); }
.prose h2:first-child { margin-top: 0; }
.prose p { color: #c4bec1; }
.principle-list { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--line); }
.principle-list li { display: grid; grid-template-columns: 70px 1fr; gap: 18px; padding: 20px 0; border-bottom: 1px solid var(--line); }
.principle-list span { color: var(--brand); font-weight: 900; }
.principle-list p { margin: 0; color: #c8c2c4; }
.safety-grid article h2 { font-size: 1.45rem; }
.privacy-stack { display: grid; gap: 18px; }
.privacy-stack article { padding: 28px 0; border-bottom: 1px solid var(--line); }
.privacy-stack h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); }
.privacy-stack p { color: #c0babe; }
.search-page-hero { padding-bottom: 34px; }
.search-results { display: grid; gap: 14px; }
.result-count { color: var(--muted); margin: 0 0 8px; }
.link-card { padding: 22px; border: 1px solid var(--line); border-radius: 14px; background: #1c1c20; }
.link-card h3 { margin: 0 0 6px; }
.link-card h3 a:hover { color: var(--accent); }
.link-card p { color: #bcb6b9; margin: 0 0 12px; }
.empty-state { padding: 44px; border: 1px dashed var(--line-strong); border-radius: 18px; text-align: center; }
.empty-state h2 { margin-top: 0; }
.empty-state p { color: var(--muted); }
.empty-state a { color: var(--accent); }
.not-found { min-height: 65vh; display: grid; place-items: center; padding: 80px 0; text-align: center; }
.status-code { margin: 0 0 12px; color: var(--brand); font-size: 1rem; font-weight: 900; letter-spacing: .22em; }
.not-found p { color: #bbb5b8; }
.not-found .hero-actions { justify-content: center; }
.site-footer { border-top: 1px solid var(--line); background: #111113; padding: 54px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr repeat(3, 1fr); gap: 34px; }
.footer-brand h2 { margin: 0; font-size: 1.7rem; }
.footer-brand p:not(.eyebrow) { color: #9e999c; max-width: 480px; }
.footer-links { display: grid; align-content: start; gap: 9px; }
.footer-links h3 { margin: 0 0 5px; font-size: .95rem; }
.footer-links a { color: #9f999d; font-size: .9rem; }
.footer-links a:hover { color: var(--accent); }
.footer-bottom { margin-top: 42px; padding-top: 20px; border-top: 1px solid var(--line); display: flex; justify-content: space-between; gap: 20px; color: #777278; font-size: .82rem; }
.footer-bottom p { margin: 0; }
.footer-bottom a:hover { color: var(--text); }
@media (max-width: 1100px) {
    .header-inner { grid-template-columns: auto auto 1fr; }
    .primary-nav { position: absolute; top: 78px; left: 24px; right: 24px; display: none; padding: 12px; background: #1b1b1f; border: 1px solid var(--line-strong); border-radius: 16px; box-shadow: var(--shadow); }
    .primary-nav.is-open { display: grid; }
    .primary-nav a { padding: 11px 12px; }
    .menu-toggle { display: inline-flex; justify-self: end; }
    .search-open { justify-self: end; }
    .hero-grid { grid-template-columns: 1fr .78fr; gap: 38px; }
    .rule-grid { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: 1.3fr repeat(3, 1fr); }
}
@media (max-width: 900px) {
    .hero-grid, .page-hero-grid, .media-note-grid, .app-strip, .two-column-grid, .final-callout-inner { grid-template-columns: 1fr; }
    .hero-visual, .page-hero figure { max-width: 720px; }
    .media-note-grid.reverse figure { order: 0; }
    .split-heading { grid-template-columns: 1fr; gap: 14px; }
    .rule-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 680px) {
    .shell, .narrow, .breadcrumbs { width: min(calc(100% - 28px), var(--shell)); }
    .header-inner { min-height: 68px; grid-template-columns: 1fr auto auto; gap: 8px; }
    .brand-mark img { width: 40px; height: 40px; }
    .brand-copy small { display: none; }
    .brand-copy strong { font-size: .98rem; }
    .primary-nav { top: 68px; left: 14px; right: 14px; }
    .search-open, .menu-toggle { padding: 8px 10px; font-size: .86rem; }
    .hero, .page-hero { padding: 40px 0 30px; }
    .hero h1, .page-hero h1, .not-found h1 { font-size: clamp(2.15rem, 12vw, 3.5rem); }
    .hero-lead, .page-hero p { font-size: 1rem; }
    .identity-list { grid-template-columns: 1fr; }
    .section { padding: 62px 0; }
    .flow-item { grid-template-columns: 46px 1fr; gap: 14px; }
    .rule-grid, .note-grid, .safety-grid { grid-template-columns: 1fr; }
    .rule-grid article { min-height: auto; }
    .index-list a { grid-template-columns: 1fr; gap: 3px; }
    .timeline::before { left: 25px; }
    .timeline-item { grid-template-columns: 52px 1fr; gap: 16px; }
    .timeline-number { width: 52px; height: 52px; font-size: .78rem; }
    .search-row { grid-template-columns: 1fr; }
    .search-row button { min-height: 46px; }
    .footer-grid { grid-template-columns: 1fr; }
    .footer-brand { grid-column: auto; }
    .footer-bottom { display: grid; }
    .final-callout-inner { padding: 22px; }
}
@media (max-width: 420px) {
    .brand-mark { gap: 8px; }
    .search-open { font-size: 0; width: 40px; height: 38px; position: relative; }
    .search-open::after { content: "搜"; font-size: .86rem; }
    .menu-toggle span { font-size: .8rem; }
    .hero-actions { display: grid; }
    .button { width: 100%; }
    .search-dialog { padding: 28px 18px 20px; }
    .article-stack article { grid-template-columns: 42px 1fr; gap: 12px; }
}