:root {
    --bg: #06111e;
    --surface: rgba(11, 24, 40, 0.84);
    --surface-soft: rgba(14, 30, 48, 0.94);
    --line: rgba(150, 214, 255, 0.16);
    --text: #eef7ff;
    --muted: #9fb3c9;
    --accent: #99e6ff;
    --accent-strong: #58b9ff;
    --accent-soft: rgba(153, 230, 255, 0.12);
    --shadow: 0 28px 70px rgba(0, 0, 0, 0.34);
    --radius: 24px;
    --font-display: "Lucida Sans Unicode", "Microsoft YaHei", sans-serif;
    --font-body: "Lucida Sans", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    color: var(--text);
    font-family: var(--font-body);
    background:
        radial-gradient(circle at 82% 14%, rgba(88, 185, 255, 0.16), transparent 26%),
        linear-gradient(180deg, rgba(153, 230, 255, 0.04), transparent 18%),
        linear-gradient(145deg, #04101b 0%, #081726 44%, #0a1b2f 100%);
}
a { color: inherit; text-decoration: none; }
.skip-link { position: absolute; left: -999px; }
.skip-link:focus { left: 20px; top: 20px; z-index: 100; background: #fff; color: #021119; padding: 10px 14px; }
.wrap { width: min(1160px, calc(100% - 44px)); margin: 0 auto; }
.site-header { position: sticky; top: 0; z-index: 20; background: rgba(4, 12, 20, 0.84); backdrop-filter: blur(20px); border-bottom: 1px solid var(--line); }
.utility-line, .header-inner, .nav, .btn-row, .footer-tail, .section-row { display: flex; gap: 14px; flex-wrap: wrap; }
.utility-line { justify-content: space-between; padding: 14px 0; color: var(--muted); font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase; }
.header-inner { align-items: center; justify-content: space-between; padding: 18px 0 20px; }
.brand { display: flex; gap: 16px; align-items: center; }
.brand-mark {
    width: 54px; height: 54px; display: grid; place-items: center; border-radius: 16px;
    color: #05111a; font-weight: 700; background: linear-gradient(135deg, var(--accent), var(--accent-strong));
}
.brand-copy strong { display: block; font-size: 20px; font-family: var(--font-display); }
.brand-copy span, .eyebrow, .meta, .footer-tail { color: var(--muted); }
.nav { padding: 6px; border-radius: 999px; border: 1px solid var(--line); background: rgba(255, 255, 255, 0.02); }
.nav-link { padding: 10px 16px; border-radius: 999px; transition: 0.2s ease; }
.nav-link:hover, .nav-link.is-active, .outline-btn:hover, .pager-link:hover { color: var(--accent); background: var(--accent-soft); }
.solid-btn, .btn, .outline-btn, .pager-item {
    min-height: 46px; display: inline-flex; align-items: center; justify-content: center; border-radius: 999px; transition: 0.2s ease;
}
.solid-btn, .btn { padding: 0 22px; color: #03111a; font-weight: 700; background: linear-gradient(135deg, var(--accent), var(--accent-strong)); }
.outline-btn { padding: 0 18px; border: 1px solid var(--line); background: rgba(255, 255, 255, 0.03); }
.compact-link { min-height: 40px; padding: 0 14px; }
.site-main { padding: 28px 0 76px; }
.hero, .category-grid, .knowledge-band, .feed-list, .page-hero, .split, .article-shell, .link-grid, .steps, .cta-band, .section-row { margin-top: 28px; }
.helpdesk-hero, .page-hero, .article-shell, .split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(320px, 0.95fr); gap: 24px; }
.helpdesk-hero { min-height: calc(100vh - 178px); align-items: center; }
.hero-copy h1, .page-hero h1, .article-shell h1 { margin: 0; font-family: var(--font-display); font-size: clamp(42px, 6vw, 72px); line-height: 1; }
.lead, p, li { line-height: 1.78; }
.eyebrow { margin: 0 0 12px; font-size: 12px; letter-spacing: 0.22em; text-transform: uppercase; }
.question-board, .category-card, .stack-card, .panel, .tile, .card, .article-body, .side-card, .footer-panel, .steps article, .cta-band {
    border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow);
}
.question-board, .category-card, .stack-card, .panel, .tile, .card, .side-card, .footer-panel, .steps article { padding: 24px; }
.question-board { background: linear-gradient(180deg, rgba(14, 30, 48, 0.96), rgba(8, 19, 31, 0.92)); }
.question-list { display: grid; gap: 14px; }
.question-list article { padding: 16px 18px; border-radius: 18px; border: 1px solid var(--line); background: rgba(255, 255, 255, 0.03); }
.question-list h3 { margin: 0 0 8px; font-size: 16px; font-family: var(--font-display); }
.category-grid, .link-grid, .steps, .footer-grid, .stack-grid { display: grid; gap: 18px; }
.category-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.category-card { min-height: 220px; display: flex; flex-direction: column; justify-content: space-between; background: var(--surface-soft); }
.knowledge-band { display: grid; grid-template-columns: minmax(0, 0.88fr) minmax(0, 1.12fr); gap: 20px; align-items: start; }
.stack-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.stack-card { min-height: 170px; display: flex; align-items: end; }
.feed-list, .stack, .article-list, .faq-list, .side-col { display: grid; gap: 18px; }
.feed-card { display: flex; justify-content: space-between; gap: 18px; align-items: center; }
.bullet, .footer-links { list-style: none; margin: 18px 0 0; padding: 0; }
.bullet li, .footer-links li { padding: 12px 0; border-bottom: 1px solid var(--line); }
.panel-grid, .link-grid { display: grid; gap: 18px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.steps { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.steps article span {
    width: 44px; height: 44px; display: inline-grid; place-items: center; border-radius: 50%;
    color: #04111a; background: linear-gradient(135deg, var(--accent), #e0f8ff); font-weight: 700;
}
.article-body { padding: 32px; }
.pager { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 8px; }
.pager-item { min-width: 46px; padding: 0 14px; border: 1px solid var(--line); background: rgba(255, 255, 255, 0.03); }
.pager-current { background: var(--accent-soft); color: var(--accent); }
.pager-disabled { opacity: 0.45; }
.site-footer { padding-bottom: 40px; }
.footer-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.footer-tail { justify-content: space-between; padding-top: 18px; margin-top: 20px; border-top: 1px solid var(--line); font-size: 13px; }
.toast {
    position: fixed; left: 50%; bottom: 84px; transform: translateX(-50%);
    padding: 12px 18px; border-radius: 999px; color: #04121b; background: #fff; opacity: 0;
    transition: opacity 0.2s ease, transform 0.2s ease;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(-8px); }
@media (max-width: 1040px) {
    .header-inner, .helpdesk-hero, .knowledge-band, .page-hero, .split, .article-shell, .section-row, .feed-card, .cta-band { display: flex; flex-direction: column; align-items: flex-start; }
    .category-grid, .panel-grid, .link-grid, .steps, .footer-grid, .stack-grid { grid-template-columns: 1fr; }
    .helpdesk-hero { min-height: auto; }
}
@media (max-width: 720px) {
    .wrap { width: min(100% - 24px, 1160px); }
    .hero-copy h1, .page-hero h1, .article-shell h1 { font-size: 36px; }
}