:root {
    --bg: #f6f8fb;
    --panel: #ffffff;
    --ink: #172033;
    --muted: #5f6c7b;
    --line: #e6ebf2;
    --brand: #225b4c;
    --brand-dark: #143a31;
    --accent: #f4b85d;
    --soft: #eef7f3;
    --shadow: 0 18px 45px rgba(23, 32, 51, .08);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    line-height: 1.72;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: rgba(255,255,255,.96);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(14px);
}
.top-nav {
    max-width: 1180px;
    margin: 0 auto;
    padding: 14px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand-logo, .footer-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    color: var(--brand-dark);
    letter-spacing: .04em;
}
.brand-logo img, .footer-logo img {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    box-shadow: 0 8px 20px rgba(34, 91, 76, .18);
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 14px;
    font-size: 14px;
    color: #2e3c4f;
}
.nav-links a { padding: 8px 4px; }
.nav-links a:hover { color: var(--brand); }
.nav-cta, .primary-button, .secondary-button, .footer-button {
    border-radius: 999px;
    padding: 10px 16px !important;
    background: var(--brand);
    color: #fff !important;
    box-shadow: 0 12px 26px rgba(34, 91, 76, .18);
}
.secondary-button {
    background: #fff;
    color: var(--brand-dark) !important;
    border: 1px solid var(--line);
    box-shadow: none;
}
.nav-toggle { display: none; }
.header-search {
    max-width: 1180px;
    margin: 0 auto 14px;
    padding: 0 20px 4px;
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 10px;
    align-items: center;
}
.header-search label { font-weight: 700; color: var(--brand-dark); }
.header-search input {
    width: 100%;
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 12px 16px;
    background: #fff;
    outline: none;
}
.header-search input:focus { border-color: var(--brand); }
.header-search button {
    border: 0;
    border-radius: 999px;
    padding: 12px 18px;
    background: var(--brand-dark);
    color: #fff;
    cursor: pointer;
}
.header-search p {
    grid-column: 2 / 4;
    margin: -2px 0 0;
    color: var(--muted);
    font-size: 13px;
}
main { overflow: hidden; }
.section, .hero {
    max-width: 1180px;
    margin: 0 auto;
    padding: 72px 20px;
}
.hero {
    display: grid;
    grid-template-columns: minmax(0, 1.04fr) minmax(320px, .96fr);
    gap: 46px;
    align-items: center;
}
.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--brand-dark);
    background: var(--soft);
    border: 1px solid #d7eadf;
    border-radius: 999px;
    padding: 6px 12px;
    font-size: 14px;
    font-weight: 700;
}
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 14px; color: var(--ink); }
h1 { font-size: clamp(34px, 5vw, 58px); letter-spacing: -.04em; }
h2 { font-size: clamp(26px, 3vw, 38px); letter-spacing: -.025em; }
h3 { font-size: 20px; }
p { margin: 0 0 14px; color: var(--muted); }
.hero-lead { font-size: 18px; color: #3f4b5c; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 24px 0; }
.hero-points {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin-top: 22px;
}
.hero-points span, .tag {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 12px 14px;
    color: #344254;
    font-weight: 700;
}
.hero-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 28px;
    padding: 16px;
    box-shadow: var(--shadow);
}
.hero-card figure { margin: 0; position: relative; overflow: hidden; border-radius: 22px; }
.hero-card figcaption, .image-description {
    font-size: 13px;
    color: var(--muted);
    margin-top: 10px;
}
.stats-strip {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-top: 14px;
}
.stats-strip div {
    background: var(--soft);
    border-radius: 18px;
    padding: 12px;
    text-align: center;
}
.stats-strip strong { display: block; color: var(--brand-dark); font-size: 22px; }
.section-head {
    max-width: 760px;
    margin-bottom: 30px;
}
.grid-4, .grid-3, .grid-2 {
    display: grid;
    gap: 18px;
}
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card, .feature-card, .step-card, .faq-item, .testimonial, .case-card, .contact-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 24px;
    padding: 22px;
    box-shadow: 0 10px 28px rgba(23, 32, 51, .05);
}
.feature-icon {
    width: 48px;
    height: 48px;
    display: grid;
    place-items: center;
    border-radius: 16px;
    background: var(--soft);
    font-size: 24px;
    margin-bottom: 14px;
}
.feature-stat, .meta-line { color: var(--brand); font-weight: 800; font-size: 14px; }
.video-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
}
.video-card {
    position: relative;
    overflow: hidden;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 24px;
    box-shadow: 0 10px 28px rgba(23, 32, 51, .05);
}
.video-thumb {
    position: relative;
    aspect-ratio: 4 / 3;
    overflow: hidden;
    background: #dfe9e5;
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .35s ease; }
.play-button {
    position: absolute;
    inset: 0;
    display: grid;
    place-items: center;
    opacity: 0;
    background: rgba(20, 58, 49, .46);
    transition: opacity .25s ease;
}
.play-button span {
    width: 62px;
    height: 62px;
    border-radius: 50%;
    display: grid;
    place-items: center;
    background: rgba(255,255,255,.93);
    color: var(--brand-dark);
    font-weight: 900;
}
.video-card:hover .play-button, .video-card:focus-within .play-button { opacity: 1; }
.video-card:hover img { transform: scale(1.06); }
.video-body { padding: 18px; }
.video-body video { display: none; }
.video-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 12px;
    color: var(--muted);
    font-size: 13px;
}
.tag-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.tag { padding: 6px 10px; font-size: 13px; }
.step-card .step { font-size: 34px; font-weight: 900; color: var(--brand); }
.timeline { border-left: 3px solid #d7eadf; padding-left: 18px; display: grid; gap: 16px; }
.timeline article { position: relative; }
.timeline article::before {
    content: "";
    position: absolute;
    left: -27px;
    top: 7px;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--accent);
}
.faq-item summary {
    cursor: pointer;
    font-weight: 800;
    color: var(--brand-dark);
}
.testimonial .rating { color: var(--brand); font-weight: 900; }
.trust-band {
    background: var(--brand-dark);
    color: #fff;
    border-radius: 28px;
    padding: 34px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    align-items: center;
}
.trust-band h2, .trust-band p { color: #fff; }
.trust-list { display: grid; gap: 10px; }
.trust-list span {
    background: rgba(255,255,255,.1);
    border: 1px solid rgba(255,255,255,.12);
    border-radius: 14px;
    padding: 10px 12px;
}
.breadcrumb {
    max-width: 1180px;
    margin: 24px auto 0;
    padding: 0 20px;
    color: var(--muted);
    font-size: 14px;
}
.page-hero {
    max-width: 1180px;
    margin: 0 auto;
    padding: 56px 20px 26px;
}
.article-content {
    max-width: 860px;
    margin: 0 auto;
    padding: 30px 20px 72px;
}
.article-content h2 { margin-top: 32px; }
.article-content ul { color: var(--muted); }
.contact-panel {
    display: grid;
    grid-template-columns: 1.1fr .9fr;
    gap: 22px;
}
.form-demo {
    display: grid;
    gap: 12px;
}
.form-demo input, .form-demo textarea, .form-demo select {
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 12px 14px;
    font: inherit;
    background: #fff;
}
.form-demo button {
    border: 0;
    border-radius: 999px;
    padding: 13px 16px;
    background: var(--brand);
    color: #fff;
    font-weight: 800;
    cursor: pointer;
}
.site-footer {
    background: #111c27;
    color: #dce5ef;
    padding: 52px 20px 24px;
}
.site-footer p, .site-footer a { color: #dce5ef; display: block; margin: 7px 0; }
.site-footer h2 { color: #fff; font-size: 18px; }
.footer-grid {
    max-width: 1180px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1.4fr .8fr 1fr;
    gap: 28px;
}
.copyright {
    max-width: 1180px;
    margin: 28px auto 0;
    padding-top: 18px;
    border-top: 1px solid rgba(255,255,255,.1);
    color: #aebccc;
    font-size: 14px;
}
@media (max-width: 980px) {
    .hero, .trust-band, .contact-panel { grid-template-columns: 1fr; }
    .grid-4, .video-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .nav-toggle { display: inline-flex; border: 1px solid var(--line); background: #fff; border-radius: 999px; padding: 8px 12px; }
    .nav-links { display: none; position: absolute; left: 20px; right: 20px; top: 68px; background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 14px; flex-direction: column; align-items: stretch; box-shadow: var(--shadow); }
    .nav-links.open { display: flex; }
}
@media (max-width: 680px) {
    .header-search { grid-template-columns: 1fr; }
    .header-search p { grid-column: 1; }
    .grid-4, .grid-3, .grid-2, .video-grid, .hero-points, .stats-strip, .footer-grid { grid-template-columns: 1fr; }
    .section, .hero { padding: 48px 16px; }
    .page-hero { padding: 38px 16px 20px; }
    .top-nav { padding-left: 16px; padding-right: 16px; }
}