:root {
    --ink: #25383b;
    --muted: #5b6870;
    --paper: #fbfbf8;
    --panel: #ffffff;
    --accent: #23727a;
    --accent-soft: #dceff0;
    --secondary: #b88a2d;
    --line: #dbe4e7;
    --shadow: 0 14px 34px rgba(30, 62, 69, 0.11);
    --radius: 18px;
    --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--font); line-height: 1.75; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
.site-header { position: sticky; top: 0; z-index: 10; background: rgba(255, 255, 255, 0.96); border-bottom: 1px solid var(--line); backdrop-filter: blur(10px); }
.header-inner { width: min(1120px, calc(100% - 40px)); min-height: 72px; margin: 0 auto; display: flex; align-items: center; gap: 28px; }
.brand-lockup { display: inline-flex; align-items: center; gap: 11px; font-weight: 760; letter-spacing: .02em; }
.brand-lockup img { width: 40px; height: 40px; border-radius: 12px; }
.site-nav { margin-left: auto; display: flex; align-items: center; gap: 8px; }
.site-nav a { padding: 8px 12px; color: #42525a; font-size: 14px; }
.site-nav a:hover, .site-nav a:focus-visible { color: var(--accent); }
.site-nav .nav-download { color: #fff; background: var(--accent); border-radius: 10px; padding-inline: 18px; }
.menu-toggle { display: none; border: 1px solid var(--line); background: #fff; border-radius: 10px; padding: 7px 11px; color: var(--ink); }
.hero { width: min(1120px, calc(100% - 40px)); margin: 0 auto; padding: 62px 0 78px; display: grid; grid-template-columns: minmax(0, 1.04fr) minmax(360px, .96fr); align-items: center; gap: 64px; }
.hero-copy { max-width: 590px; }
.eyebrow { margin: 0 0 14px; color: var(--accent); font-size: 13px; font-weight: 760; letter-spacing: .13em; text-transform: uppercase; }
h1 { margin: 0; font-size: clamp(34px, 4vw, 58px); line-height: 1.16; letter-spacing: -.015em; }
.hero-copy > p { margin: 22px 0 0; color: var(--muted); font-size: 17px; max-width: 560px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 28px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 46px; padding: 0 20px; border-radius: 12px; font-weight: 700; border: 1px solid transparent; }
.button-primary { color: #fff; background: var(--accent); box-shadow: 0 8px 18px color-mix(in srgb, var(--accent) 25%, transparent); }
.button-quiet { color: var(--accent); background: #fff; border-color: var(--line); }
.hero-note { margin: 14px 0 0; color: #718087; font-size: 13px; }
.hero-media { min-height: 420px; display: flex; align-items: center; justify-content: center; position: relative; }
.hero-media::before { content: ""; position: absolute; width: 78%; height: 78%; background: var(--accent-soft); border-radius: 40% 60% 46% 54%; transform: rotate(-8deg); }
.preview-stack { position: relative; display: flex; align-items: center; gap: 13px; z-index: 1; }
.preview-stack img { width: min(31vw, 184px); max-width: 184px; height: auto; border-radius: 15px; border: 7px solid #fff; box-shadow: var(--shadow); object-fit: contain; background: #fff; }
.preview-stack img:nth-child(2) { transform: translateY(-24px); }
.preview-stack img:nth-child(3) { transform: translateY(18px); }
.section { padding: 76px 0; }
.section-inner { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 22px; margin-bottom: 28px; }
h2 { margin: 0; font-size: clamp(24px, 3vw, 34px); line-height: 1.25; }
.section-kicker { margin: 0; color: var(--muted); max-width: 560px; }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.feature-card, .faq-item, .guide-card { padding: 22px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); box-shadow: 0 7px 20px rgba(39, 73, 80, 0.05); }
.feature-card h3, .guide-card h3 { margin: 0 0 8px; font-size: 18px; }
.feature-card p, .guide-card p { margin: 0; color: var(--muted); font-size: 15px; }
.screens-section { background: #f6faf9; }
.screen-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); align-items: center; gap: 26px; }
.screen-card { margin: 0; padding: 20px; border-radius: var(--radius); background: #fff; border: 1px solid var(--line); text-align: center; }
.screen-card img { width: min(100%, 300px); height: 340px; margin: 0 auto 14px; object-fit: contain; }
.screen-card figcaption { color: var(--muted); font-size: 14px; }
.split-section { display: grid; grid-template-columns: .85fr 1.15fr; gap: 42px; align-items: start; }
.faq-list { display: grid; gap: 12px; }
.faq-item summary { cursor: pointer; font-weight: 700; }
.faq-item p { margin: 13px 0 0; color: var(--muted); }
.guide-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.page-intro { width: min(820px, calc(100% - 40px)); margin: 0 auto; padding: 72px 0 34px; }
.page-intro h1 { font-size: clamp(34px, 5vw, 52px); }
.page-intro > p { margin: 20px 0 0; color: var(--muted); font-size: 17px; }
.article-section { padding: 24px 0 82px; }
.article-section .section-inner { max-width: 820px; }
.article-section h2 { margin-top: 38px; }
.article-section p { color: var(--muted); }
.site-footer { padding: 34px 20px 42px; text-align: center; color: #77858a; font-size: 13px; border-top: 1px solid var(--line); }
.site-footer p { margin: 4px 0; }
.alt-rail .hero { grid-template-columns: .8fr 1.2fr; }
.alt-rail .hero-media { order: 2; }
.alt-rail .preview-stack { gap: 22px; }
.alt-catalog .hero { grid-template-columns: 1fr .9fr; }
.alt-catalog .preview-stack { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.alt-catalog .preview-stack img { width: min(18vw, 150px); }
.alt-catalog .preview-stack img:nth-child(2) { transform: translateY(30px); }
.alt-catalog .preview-stack img:nth-child(3) { transform: translateY(0); }
.alt-narrative .hero { grid-template-columns: 1.1fr .9fr; }
.alt-narrative .hero-media::before { width: 62%; height: 90%; border-radius: 28px; transform: rotate(5deg); }
.alt-narrative .preview-stack { flex-direction: row; gap: 8px; }
.alt-narrative .preview-stack img { width: min(30vw, 170px); }
.alt-narrative .preview-stack img:nth-child(2) { transform: translateY(-22px); }
.alt-narrative .preview-stack img:nth-child(3) { transform: translateY(22px); }
.alt-slate { --paper: #f4f7f8; --accent-soft: #e4eff0; }
.alt-slate .hero { padding-bottom: 60px; }
.alt-slate .section:nth-of-type(even) { background: #fff; }
.alt-index .hero { grid-template-columns: .95fr 1.05fr; }
.alt-index .hero-media { align-items: flex-start; padding-top: 14px; }
.alt-index .preview-stack img:nth-child(1) { transform: translateY(25px); }
.alt-index .preview-stack img:nth-child(2) { transform: translateY(-20px); }
.alt-index .preview-stack img:nth-child(3) { transform: translateY(48px); }

@media (max-width: 820px) {
    .header-inner { width: min(100% - 28px, 680px); min-height: 64px; }
    .menu-toggle { display: inline-flex; margin-left: auto; }
    .site-nav { display: none; position: absolute; top: 64px; left: 14px; right: 14px; padding: 12px; flex-direction: column; align-items: stretch; background: #fff; border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); }
    .site-nav.is-open { display: flex; }
    .site-nav a { text-align: center; }
    .hero { width: min(100% - 28px, 680px); padding: 34px 0 40px; grid-template-columns: 1fr; gap: 22px; }
    .hero-media { min-height: 250px; }
    .hero-media, .alt-rail .hero-media { order: 2; }
    .alt-rail .hero, .alt-catalog .hero, .alt-narrative .hero, .alt-index .hero { grid-template-columns: 1fr; }
    .preview-stack img { width: min(26vw, 130px); }
    .section-inner { width: min(100% - 28px, 680px); }
    .section { padding: 56px 0; }
    .section-heading { display: block; }
    .section-kicker { margin-top: 9px; }
    .feature-grid, .screen-grid, .guide-grid, .split-section { grid-template-columns: 1fr; }
    .screen-card img { height: auto; max-height: 340px; }
    .page-intro { width: min(100% - 28px, 680px); padding-top: 48px; }
    .article-section { padding-bottom: 58px; }
}