:root {
    --accent: #e85d2a;
    --accent-dark: #a83d18;
    --accent-soft: #fff1ea;
    --ink: #182334;
    --muted: #667085;
    --line: #dfe4ea;
    --panel: #f4f6f8;
    --white: #ffffff;
    --container: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    color: var(--ink);
    background: var(--white);
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
    line-height: 1.7;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; height: auto; }
.container { width: min(var(--container), calc(100% - 48px)); margin: 0 auto; }
.site-header { position: relative; z-index: 20; background: rgba(255,255,255,.96); border-bottom: 1px solid var(--line); }
.header-inner { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.brand { display: inline-flex; align-items: center; gap: 11px; font-size: 20px; font-weight: 800; }
.brand img { width: 42px; height: 42px; border-radius: 8px; }
.site-nav { display: flex; align-items: center; gap: 28px; }
.nav-link { color: #475467; font-size: 15px; }
.nav-link:hover, .nav-link.active { color: var(--accent-dark); }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; padding: 0 24px; border-radius: 6px; background: var(--accent); color: #fff; font-weight: 750; border: 1px solid var(--accent); }
.button:hover { background: var(--accent-dark); border-color: var(--accent-dark); }
.button-small { min-height: 40px; padding: 0 18px; }
.menu-toggle { display: none; width: 42px; height: 42px; border: 1px solid var(--line); background: #fff; border-radius: 6px; padding: 10px; }
.menu-toggle span { display: block; height: 2px; background: var(--ink); margin: 4px 0; }
.hero { background: linear-gradient(180deg, #fff 0%, var(--panel) 100%); border-bottom: 1px solid var(--line); overflow: hidden; }
.hero-inner { min-height: 650px; display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(390px, .95fr); align-items: center; gap: 72px; padding: 48px 0 58px; }
.eyebrow { color: var(--accent-dark); font-size: 13px; font-weight: 800; letter-spacing: 0; text-transform: uppercase; margin-bottom: 14px; }
h1, h2, h3, p { margin-top: 0; }
.hero h1 { max-width: 650px; margin-bottom: 18px; font-size: clamp(42px, 5vw, 68px); line-height: 1.12; letter-spacing: 0; }
.hero-copy > p { max-width: 620px; color: #4b5565; font-size: 18px; line-height: 1.85; }
.hero-actions { display: flex; align-items: center; gap: 26px; margin: 28px 0 34px; }
.text-link { color: var(--accent-dark); font-weight: 750; }
.hero-facts { display: flex; gap: 0; list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--line); }
.hero-facts li { min-width: 120px; padding: 18px 24px 0 0; }
.hero-facts strong, .hero-facts span { display: block; }
.hero-facts strong { font-size: 15px; }
.hero-facts span { color: var(--muted); font-size: 12px; }
.hero-media { position: relative; height: 510px; display: flex; align-items: center; justify-content: center; }
.hero-phone { position: absolute; width: 230px; overflow: hidden; border-radius: 22px; border: 7px solid #fff; background: #fff; box-shadow: 0 18px 55px rgba(20,30,45,.18); }
.hero-phone img { width: 100%; }
.primary-phone { z-index: 2; transform: translate(-66px, 0) rotate(-3deg); }
.secondary-phone { z-index: 1; transform: translate(108px, 24px) rotate(5deg); opacity: .92; }
.media-label { position: absolute; right: 0; bottom: 26px; padding: 8px 12px; background: #fff; border: 1px solid var(--line); color: var(--muted); font-size: 11px; font-weight: 800; }
.section { padding: 88px 0; }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 24px; margin-bottom: 34px; }
.section-heading h2 { margin-bottom: 0; font-size: 34px; line-height: 1.25; }
.section-note { max-width: 560px; color: var(--muted); }
.gallery { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; align-items: start; }
.shot { position: relative; margin: 0; padding: 18px; background: var(--panel); border: 1px solid var(--line); border-radius: 8px; }
.shot img { width: min(100%, 399px); margin: 0 auto; border-radius: 6px; }
.shot figcaption { padding-top: 13px; color: #4b5565; font-size: 14px; text-align: center; }
.stack-gallery .shot:nth-child(2) { margin-top: 42px; }
.mosaic-gallery { grid-template-columns: 1.2fr .9fr .9fr; }
.mosaic-gallery .shot-wide { padding-bottom: 28px; }
.rail-gallery { position: relative; padding-left: 44px; }
.rail-gallery::before { content: ""; position: absolute; left: 10px; top: 0; bottom: 0; width: 1px; background: var(--accent); }
.shot-index { position: absolute; left: -45px; top: 15px; color: var(--accent-dark); font-weight: 800; }
.feature-section { background: var(--panel); border-block: 1px solid var(--line); }
.feature-layout { display: grid; grid-template-columns: 310px 1fr; gap: 72px; }
.sticky-heading { display: block; align-self: start; }
.sticky-heading .section-note { margin-top: 14px; }
.feature-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.feature-grid article { padding: 26px; background: #fff; border: 1px solid var(--line); border-radius: 8px; }
.feature-grid article > span { color: var(--accent); font-size: 12px; font-weight: 900; }
.feature-grid h3 { margin: 9px 0; font-size: 20px; }
.feature-grid p { margin-bottom: 0; color: var(--muted); }
.deep-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.deep-link { position: relative; padding: 30px 70px 30px 30px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.deep-link span { color: var(--accent-dark); font-size: 13px; font-weight: 800; }
.deep-link strong { display: block; margin: 7px 0; font-size: 22px; }
.deep-link p { margin: 0; color: var(--muted); }
.deep-link b { position: absolute; right: 28px; top: 50%; transform: translateY(-50%); color: var(--accent); font-size: 30px; }
.download-band { padding: 54px 0; background: var(--accent-dark); color: #fff; }
.download-inner { display: flex; justify-content: space-between; align-items: center; gap: 30px; }
.download-inner span { font-size: 12px; font-weight: 800; opacity: .7; }
.download-inner h2 { margin: 5px 0 0; font-size: 30px; }
.button-light { background: #fff; color: var(--accent-dark); border-color: #fff; }
.button-light:hover { background: var(--accent-soft); color: var(--accent-dark); border-color: var(--accent-soft); }
.site-footer { padding: 42px 0; background: #111820; color: #d5dbe3; }
.footer-inner { text-align: center; }
.footer-brand { display: inline-flex; align-items: center; gap: 10px; color: #fff; }
.footer-brand img { border-radius: 7px; }
.footer-nav { display: flex; justify-content: center; gap: 24px; margin: 22px 0; font-size: 14px; }
.disclaimer { max-width: 760px; margin: 0 auto 10px; color: #aeb7c3; font-size: 13px; text-align: center; }
.copyright { margin-bottom: 0; color: #8792a0; font-size: 12px; text-align: center; }
.inner-main { background: #fff; }
.inner-hero { padding: 76px 0 68px; background: var(--panel); border-bottom: 1px solid var(--line); }
.narrow { max-width: 850px; }
.inner-hero h1 { margin-bottom: 18px; font-size: 46px; line-height: 1.25; }
.inner-hero p { color: var(--muted); font-size: 18px; }
.inner-hero .button { margin-top: 12px; }
.article-layout { display: grid; grid-template-columns: 220px 1fr; gap: 70px; align-items: start; }
.article-index { position: sticky; top: 22px; display: grid; gap: 10px; padding: 20px; border: 1px solid var(--line); border-radius: 8px; }
.article-index strong { margin-bottom: 6px; }
.article-index a { color: var(--muted); font-size: 14px; }
.article-index a:hover { color: var(--accent-dark); }
.prose { max-width: 800px; }
.prose h2 { margin: 48px 0 15px; font-size: 27px; }
.prose h2:first-child { margin-top: 0; }
.prose p, .prose li { color: #3f4a59; }
.prose a { color: var(--accent-dark); font-weight: 700; }
.faq-layout { display: grid; grid-template-columns: 300px 1fr; gap: 72px; align-items: start; }
.faq-intro { position: sticky; top: 22px; }
.faq-intro > span { color: var(--accent-dark); font-weight: 800; font-size: 13px; }
.faq-intro h2 { margin: 8px 0; font-size: 34px; }
.faq-intro p { color: var(--muted); }
.faq-list { border-top: 1px solid var(--line); }
.faq-item { border-bottom: 1px solid var(--line); }
.faq-item summary { position: relative; cursor: pointer; list-style: none; padding: 22px 48px 22px 0; font-weight: 750; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary span { position: absolute; right: 8px; color: var(--accent); font-size: 24px; }
.faq-item[open] summary span { transform: rotate(45deg); }
.faq-item div { padding: 0 48px 22px 0; color: var(--muted); }
.theme-b .hero-inner { grid-template-columns: minmax(0, .92fr) minmax(440px, 1.08fr); }
.theme-b .hero-media { background: var(--accent-soft); border-radius: 8px; border: 1px solid #cde6e3; }
.theme-b .primary-phone { transform: translate(-82px, 2px); }
.theme-b .secondary-phone { transform: translate(96px, 14px); }
.theme-c .hero { border-top: 6px solid var(--accent); }
.theme-c .hero-media { justify-content: flex-end; }
.theme-c .hero-phone { border-radius: 5px; box-shadow: 0 12px 35px rgba(32,36,45,.14); }
.theme-c .primary-phone { transform: translate(-122px, -5px); }
.theme-c .secondary-phone { transform: translate(65px, 38px); }

@media (max-width: 900px) {
    .container { width: min(100% - 32px, var(--container)); }
    .menu-toggle { display: block; }
    .site-nav { display: none; position: absolute; top: 76px; left: 16px; right: 16px; padding: 18px; background: #fff; border: 1px solid var(--line); box-shadow: 0 12px 30px rgba(20,30,45,.12); flex-direction: column; align-items: stretch; gap: 4px; }
    .site-nav.open { display: flex; }
    .nav-link { padding: 10px 4px; }
    .hero-inner, .theme-b .hero-inner { min-height: auto; grid-template-columns: 1fr; gap: 24px; padding: 40px 0 34px; }
    .hero-copy { order: 1; }
    .hero-media { order: 2; height: 365px; }
    .hero h1 { font-size: 42px; }
    .hero-copy > p { font-size: 16px; }
    .hero-phone { width: 165px; border-width: 5px; border-radius: 16px; }
    .primary-phone, .theme-b .primary-phone, .theme-c .primary-phone { transform: translate(-52px, 0) rotate(-2deg); }
    .secondary-phone, .theme-b .secondary-phone, .theme-c .secondary-phone { transform: translate(64px, 18px) rotate(4deg); }
    .media-label { right: 10px; bottom: 5px; }
    .section { padding: 62px 0; }
    .gallery, .mosaic-gallery, .feature-grid, .deep-grid { grid-template-columns: 1fr; }
    .stack-gallery .shot:nth-child(2) { margin-top: 0; }
    .rail-gallery { padding-left: 0; }
    .rail-gallery::before, .shot-index { display: none; }
    .feature-layout, .article-layout, .faq-layout { grid-template-columns: 1fr; gap: 34px; }
    .article-index, .faq-intro { position: static; }
    .download-inner { align-items: flex-start; flex-direction: column; }
    .inner-hero h1 { font-size: 36px; }
}

@media (max-width: 520px) {
    .header-inner { min-height: 68px; }
    .site-nav { top: 68px; }
    .brand { font-size: 18px; }
    .brand img { width: 38px; height: 38px; }
    .hero-inner { padding-top: 30px; }
    .hero h1 { font-size: 36px; }
    .hero-actions { align-items: flex-start; flex-direction: column; gap: 15px; margin: 22px 0 24px; }
    .hero-facts { display: grid; grid-template-columns: repeat(3, 1fr); }
    .hero-facts li { min-width: 0; padding-right: 8px; }
    .hero-facts strong { font-size: 13px; }
    .hero-media { height: 285px; }
    .hero-phone { width: 150px; }
    .section-heading { align-items: flex-start; flex-direction: column; }
    .section-heading h2 { font-size: 29px; }
    .shot { padding: 12px; }
    .feature-grid article { padding: 22px; }
    .deep-link { padding: 24px 54px 24px 22px; }
    .deep-link strong { font-size: 19px; }
    .download-inner h2 { font-size: 25px; }
    .inner-hero { padding: 54px 0 48px; }
    .inner-hero h1 { font-size: 31px; }
    .inner-hero p { font-size: 16px; }
    .faq-item summary { padding-right: 38px; }
    .faq-item div { padding-right: 0; }
}