:root {
    --ink: #1d1a17;
    --paper: #f6f1e6;
    --staff: #c9bfad;
    --muted: #5e574c;
    --note: #7a2e2e;
    --white: #fffaf2;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: "Georgia", "Songti SC", "SimSun", "Microsoft YaHei", serif;
    background: var(--paper);
    color: var(--ink);
    line-height: 2;
    letter-spacing: 0.02em;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
.container { width: min(1080px, calc(100% - 32px)); margin: 0 auto; }

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 22px;
    border: 0;
    background: var(--ink);
    color: var(--white);
    font-weight: 700;
    font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
    letter-spacing: 0.06em;
}
.btn:hover { background: #000; }
.btn-ghost { background: transparent; color: var(--ink); box-shadow: inset 0 0 0 1.5px var(--ink); }
.btn-lg { padding: 13px 26px; font-size: 15px; }

.score-bar {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.18em;
    font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
}
.score-bar span { padding: 8px; text-align: center; border-bottom: 4px double var(--ink); }
.score-bar span:nth-child(odd) { background: var(--white); }
.score-bar span:nth-child(even) { background: #efe8d8; }

.site-nav {
    position: sticky;
    top: 0;
    z-index: 40;
    background: var(--white);
    border-bottom: 1px solid var(--staff);
}
.nav-wrap { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 14px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.logo-mark {
    width: 34px;
    height: 34px;
    border: 2px solid var(--ink);
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-size: 14px;
}
.nav-menu { display: flex; gap: 18px; flex-wrap: wrap; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.nav-menu a { font-size: 14px; color: var(--muted); font-weight: 600; }
.nav-menu a:hover, .nav-menu a.active { color: var(--note); }
.nav-actions { display: flex; gap: 8px; }
.nav-toggle { display: none; }
.nav-burger { display: none; border: 1.5px solid var(--ink); padding: 7px 12px; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }

.hero {
    padding: 58px 0 44px;
    background:
        repeating-linear-gradient(
            to bottom,
            transparent 0 31px,
            var(--staff) 31px 32px
        );
}
.hero-grid { display: grid; grid-template-columns: 1.08fr .92fr; gap: 40px; align-items: center; }
.tag {
    display: inline-block;
    color: var(--note);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.16em;
    margin-bottom: 14px;
    font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
}
.hero h1 { font-size: clamp(28px, 4vw, 42px); line-height: 1.45; margin-bottom: 16px; }
.hero-kicker { color: var(--note); font-weight: 700; margin-bottom: 10px; }
.hero p { color: var(--muted); margin-bottom: 22px; }
.measure {
    background: var(--white);
    border-left: 3px solid var(--ink);
    padding: 18px 20px;
}
.meta { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 14px; font-size: 13px; color: var(--muted); font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.hero-visual img { width: 100%; border: 1px solid var(--ink); }

.data-band { background: var(--ink); color: var(--white); padding: 26px 0; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.data-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; text-align: center; }
.data-num { font-size: 28px; font-weight: 800; line-height: 1.3; }
.data-label { font-size: 13px; color: #d8d0c2; }

.section { padding: 72px 0; }
.section.alt { background: var(--white); }
.section-head { text-align: center; margin-bottom: 32px; }
.section-head h2 { font-size: 26px; margin-bottom: 12px; }
.section-head p { color: var(--muted); }

.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card { background: var(--white); border-top: 4px double var(--ink); padding: 22px 18px; }
.card h3 { margin: 10px 0; }
.card p { color: var(--muted); font-size: 15px; }
.icon { color: var(--note); font-size: 18px; letter-spacing: 0.2em; }
.solution-card { padding: 0; border-top: 4px double var(--ink); }
.solution-card img { height: 168px; width: 100%; object-fit: cover; }
.solution-card div { padding: 18px; }
.price { font-size: 22px; color: var(--note); font-weight: 800; margin: 8px 0 10px; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.card.main { background: #efe8d8; }

.cta { padding: 64px 0; text-align: center; background: var(--ink); color: var(--white); }
.cta h2 { font-size: 28px; margin-bottom: 12px; }
.cta p { margin-bottom: 18px; color: #d8d0c2; }
.cta .btn { background: var(--white); color: var(--ink); }
.cta .btn-ghost { background: transparent; color: var(--white); box-shadow: inset 0 0 0 1.5px var(--white); }
.cta-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }

.site-footer { background: #141210; color: #d8d0c2; padding: 44px 0 16px; }
.footer-grid { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 20px; margin-bottom: 18px; }
.footer-grid h4 { color: #fff; margin-bottom: 10px; }
.footer-grid a, .footer-grid p { display: block; margin-bottom: 10px; font-size: 14px; color: #d8d0c2; }
.logo-light { color: #fff; }
.footer-bottom { border-top: 1px solid #3a342c; padding-top: 12px; text-align: center; font-size: 12px; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }

.page-hero { padding: 44px 0 10px; text-align: center; }
.page-hero h1 { font-size: 30px; margin-bottom: 12px; }
.page-hero p { color: var(--muted); }

.dl-list { display: grid; gap: 18px; }
.dl-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    background: var(--white);
    border-top: 4px double var(--ink);
    padding: 22px;
}
.dl-item.main { background: #efe8d8; }
.specs { display: flex; gap: 10px; flex-wrap: wrap; margin: 10px 0; font-size: 12px; color: var(--muted); font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
.specs span { border-bottom: 1px solid var(--staff); padding-bottom: 2px; }
.shot { max-width: 840px; margin: 28px auto 0; }
.shot img { border: 1px solid var(--ink); }

.help-list { display: grid; gap: 18px; max-width: 840px; margin: 0 auto; }
.help-box { background: var(--white); border-top: 4px double var(--ink); padding: 24px; }
.help-box h3 { margin-bottom: 10px; }
.help-box p { color: var(--muted); margin-bottom: 10px; }

@media (max-width: 992px) {
    .nav-burger { display: inline-block; }
    .nav-toggle:checked + .nav-burger + .nav-menu { display: flex; }
    .nav-menu {
        display: none;
        position: absolute;
        left: 16px;
        right: 16px;
        top: 122px;
        background: var(--white);
        border: 1px solid var(--ink);
        padding: 12px;
        flex-direction: column;
    }
    .hero-grid, .grid-3, .footer-grid { grid-template-columns: 1fr 1fr; }
    .score-bar { grid-template-columns: 1fr 1fr; }
    .data-grid { grid-template-columns: 1fr 1fr; }
    .dl-item { flex-direction: column; text-align: center; }
    .nav-actions .btn-ghost { display: none; }
}

@media (max-width: 640px) {
    .hero-grid, .grid-3, .footer-grid { grid-template-columns: 1fr; }
}