:root {
    --brand: #e31b23;
    --brand-dark: #b91118;
    --brand-soft: #fff1f2;
    --ink: #17202a;
    --muted: #5f6b7a;
    --line: #e7edf3;
    --page: #f6f8fb;
    --card: #ffffff;
    --nav: rgba(255, 255, 255, .92);
    --blue: #1d4ed8;
    --green: #15803d;
    --orange: #c2410c;
    --purple: #6d28d9;
    --radius: 18px;
    --shadow: 0 18px 50px rgba(15, 23, 42, .10);
    --shadow-sm: 0 8px 24px rgba(15, 23, 42, .07);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "Noto Sans SC", Arial, sans-serif;
    color: var(--ink);
    background: radial-gradient(circle at 10% 0%, #fff4f4 0, transparent 28rem), var(--page);
    line-height: 1.72;
}
a { color: inherit; }
.skip-link {
    position: absolute;
    left: -999px;
    top: 0;
    background: var(--brand);
    color: #fff;
    padding: .75rem 1rem;
    z-index: 9999;
}
.skip-link:focus { left: 1rem; top: 1rem; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(18px);
    background: var(--nav);
    border-bottom: 1px solid rgba(231, 237, 243, .9);
}
.navbar {
    max-width: 1200px;
    margin: 0 auto;
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.2rem;
    padding: 0 1.25rem;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: .75rem;
    text-decoration: none;
    font-weight: 800;
    letter-spacing: -.02em;
}
.brand img {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    box-shadow: 0 8px 18px rgba(227, 27, 35, .18);
}
.brand small {
    display: block;
    color: var(--muted);
    font-size: .78rem;
    font-weight: 600;
    letter-spacing: 0;
}
.nav-links {
    display: flex;
    align-items: center;
    gap: .25rem;
    list-style: none;
    margin: 0;
    padding: 0;
    flex-wrap: wrap;
    justify-content: flex-end;
}
.nav-links a {
    display: inline-flex;
    align-items: center;
    padding: .54rem .82rem;
    border-radius: 999px;
    text-decoration: none;
    color: #465161;
    font-size: .94rem;
    font-weight: 650;
}
.nav-links a:hover, .nav-links a.active {
    color: var(--brand);
    background: var(--brand-soft);
}
.nav-cta {
    background: var(--brand) !important;
    color: #fff !important;
    box-shadow: 0 10px 22px rgba(227, 27, 35, .20);
}
main { min-height: 65vh; }
.container {
    width: min(1200px, calc(100% - 2.5rem));
    margin: 0 auto;
}
.hero {
    margin: 2rem auto 4rem;
    padding: clamp(2.2rem, 5vw, 5rem);
    border-radius: 30px;
    color: #fff;
    overflow: hidden;
    position: relative;
    background:
        linear-gradient(135deg, rgba(12, 18, 34, .95), rgba(20, 34, 66, .96)),
        radial-gradient(circle at 90% 10%, rgba(227, 27, 35, .35), transparent 26rem);
    box-shadow: var(--shadow);
}
.hero::after {
    content: "";
    position: absolute;
    inset: auto -8rem -10rem auto;
    width: 28rem;
    height: 28rem;
    border-radius: 999px;
    background: rgba(227, 27, 35, .18);
    filter: blur(8px);
}
.hero-grid {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1.12fr .88fr;
    gap: clamp(2rem, 5vw, 4rem);
    align-items: center;
}
.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: .5rem;
    padding: .42rem .82rem;
    border-radius: 999px;
    background: rgba(255,255,255,.10);
    border: 1px solid rgba(255,255,255,.18);
    color: rgba(255,255,255,.88);
    font-size: .88rem;
    font-weight: 700;
}
h1, h2, h3 { line-height: 1.24; letter-spacing: -.035em; }
h1 {
    margin: 1.1rem 0 1rem;
    font-size: clamp(2.4rem, 6vw, 4.8rem);
}
h1 span, .text-brand { color: #ff6b70; }
.hero p.lead {
    max-width: 720px;
    margin: 0 0 1.8rem;
    color: rgba(255,255,255,.82);
    font-size: clamp(1.04rem, 1.6vw, 1.22rem);
}
.actions {
    display: flex;
    gap: .9rem;
    flex-wrap: wrap;
    align-items: center;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: .45rem;
    min-height: 48px;
    padding: .82rem 1.25rem;
    border-radius: 13px;
    text-decoration: none;
    font-weight: 800;
    border: 1px solid transparent;
    transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary {
    color: #fff;
    background: var(--brand);
    box-shadow: 0 14px 28px rgba(227,27,35,.25);
}
.btn-primary:hover { background: var(--brand-dark); }
.btn-white {
    color: #111827;
    background: #fff;
    border-color: rgba(255,255,255,.5);
}
.btn-outline {
    color: var(--brand);
    background: #fff;
    border-color: #fecdd3;
}
.btn-ghost {
    color: #fff;
    border-color: rgba(255,255,255,.25);
    background: rgba(255,255,255,.08);
}
.hero-panel {
    border-radius: 24px;
    padding: 1.4rem;
    background: rgba(255,255,255,.08);
    border: 1px solid rgba(255,255,255,.18);
    box-shadow: inset 0 1px 0 rgba(255,255,255,.08);
}
.mode-stack { display: grid; gap: .86rem; }
.mode-card {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: .86rem;
    align-items: start;
    padding: 1rem;
    border-radius: 18px;
    background: rgba(255,255,255,.09);
    border: 1px solid rgba(255,255,255,.12);
}
.mode-badge {
    width: 2.2rem;
    height: 2.2rem;
    display: grid;
    place-items: center;
    border-radius: .8rem;
    background: rgba(255,107,112,.18);
    color: #ffb4b7;
    font-weight: 900;
}
.mode-card h3 { margin: 0 0 .15rem; font-size: 1rem; color: #fff; }
.mode-card p { margin: 0; color: rgba(255,255,255,.72); font-size: .92rem; line-height: 1.58; }
.stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin: -2.8rem auto 4rem;
    position: relative;
    z-index: 2;
}
.stat {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 1.25rem;
    box-shadow: var(--shadow-sm);
}
.stat strong { display: block; font-size: 1.55rem; letter-spacing: -.03em; color: var(--ink); }
.stat span { color: var(--muted); font-size: .92rem; }
.section { margin: 4.5rem 0; }
.section-head { max-width: 760px; margin: 0 auto 2.2rem; text-align: center; }
.section-kicker {
    display: inline-block;
    color: var(--brand);
    background: var(--brand-soft);
    border: 1px solid #fecdd3;
    font-weight: 800;
    border-radius: 999px;
    padding: .38rem .8rem;
    font-size: .84rem;
}
.section-head h2 { margin: .75rem 0 .7rem; font-size: clamp(1.8rem, 3.5vw, 2.8rem); }
.section-head p { color: var(--muted); margin: 0; font-size: 1.04rem; }
.grid { display: grid; gap: 1.25rem; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.card {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 1.35rem;
    box-shadow: var(--shadow-sm);
}
.card h3 { margin: 0 0 .55rem; font-size: 1.14rem; }
.card p { margin: 0; color: var(--muted); }
.tag {
    display: inline-flex;
    align-items: center;
    padding: .22rem .55rem;
    border-radius: 999px;
    background: #eef2ff;
    color: #3730a3;
    font-weight: 800;
    font-size: .76rem;
    margin-bottom: .7rem;
}
.feature-icon {
    width: 2.75rem;
    height: 2.75rem;
    display: grid;
    place-items: center;
    border-radius: 1rem;
    background: var(--brand-soft);
    color: var(--brand);
    font-weight: 900;
    margin-bottom: 1rem;
}
.callout {
    padding: 1.5rem;
    border-radius: 20px;
    border: 1px solid #bfdbfe;
    background: linear-gradient(135deg, #eff6ff, #fff);
}
.callout strong { color: var(--blue); }
.table-wrap {
    overflow-x: auto;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
}
table { width: 100%; border-collapse: collapse; min-width: 720px; }
th, td { text-align: left; padding: 1rem; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: #f8fafc; color: #334155; font-size: .93rem; }
tr:last-child td { border-bottom: 0; }
kbd {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 1.9rem;
    padding: .12rem .42rem;
    border-radius: .45rem;
    background: #0f172a;
    color: #fff;
    font-size: .82rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
.timeline { position: relative; display: grid; gap: 1rem; }
.timeline-item { display: grid; grid-template-columns: 130px 1fr; gap: 1rem; }
.timeline-date { color: var(--brand); font-weight: 900; padding-top: .8rem; }
.download-box {
    margin: 2rem 0 0;
    padding: clamp(1.8rem, 4vw, 3rem);
    border-radius: 28px;
    background: linear-gradient(135deg, #fff, #fff1f2);
    border: 1px solid #fecdd3;
    box-shadow: var(--shadow);
    text-align: center;
}
.download-meta {
    max-width: 780px;
    margin: 1.5rem auto 0;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: .8rem;
}
.meta-chip {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: .8rem;
}
.meta-chip strong { display: block; }
.meta-chip span { color: var(--muted); font-size: .86rem; }
.notice {
    color: var(--muted);
    background: #fff;
    border: 1px dashed #cbd5e1;
    border-radius: 16px;
    padding: 1rem;
}
.faq-list { display: grid; gap: .9rem; }
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: 16px; overflow: hidden; box-shadow: var(--shadow-sm); }
.faq-question { width: 100%; display: flex; justify-content: space-between; gap: 1rem; text-align: left; padding: 1.1rem 1.25rem; border: 0; background: #fff; font: inherit; font-weight: 800; cursor: pointer; color: var(--ink); }
.faq-question::after { content: "+"; color: var(--brand); font-weight: 900; }
.faq-item.open .faq-question::after { content: "−"; }
.faq-answer { display: none; padding: 0 1.25rem 1.25rem; color: var(--muted); }
.faq-item.open .faq-answer { display: block; }
.site-footer {
    margin-top: 5rem;
    padding: 2.5rem 0;
    border-top: 1px solid var(--line);
    color: var(--muted);
    background: #fff;
}
.footer-grid {
    width: min(1200px, calc(100% - 2.5rem));
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}
.footer-links { display: flex; gap: 1rem; flex-wrap: wrap; }
.footer-links a { color: var(--muted); text-decoration: none; }
.footer-links a:hover { color: var(--brand); }
@media (max-width: 980px) {
    .hero-grid, .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .stats, .download-meta { grid-template-columns: repeat(2, 1fr); }
    .navbar { align-items: flex-start; flex-direction: column; padding: .9rem 1.25rem; }
    .nav-links { justify-content: flex-start; }
    .timeline-item { grid-template-columns: 1fr; gap: .2rem; }
}
@media (max-width: 560px) {
    .container { width: min(100% - 1.4rem, 1200px); }
    .hero { border-radius: 22px; padding: 2rem 1.2rem; }
    .stats, .download-meta { grid-template-columns: 1fr; margin-top: 1rem; }
    .nav-links a { padding: .42rem .58rem; font-size: .88rem; }
}