:root {
    --bg: #f4f5f7;
    --surface: #ffffff;
    --text: #1f2530;
    --muted: #5f6877;
    --line: #e2e5ea;
    --blue: #2864dc;
    --blue-dark: #1846a1;
    --blue-soft: #edf3ff;
    --green: #2a9c57;
    --amber: #cb7927;
    --radius: 12px;
    --shadow: 0 2px 5px rgba(20, 28, 42, 0.03);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--text);
    background: var(--bg);
    font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
    text-decoration: none;
}

button,
input {
    color: inherit;
    font: inherit;
}

button:focus-visible,
a:focus-visible,
input:focus-visible {
    outline: 3px solid rgba(40, 100, 220, 0.25);
    outline-offset: 2px;
}

.skip-link {
    position: fixed;
    top: -60px;
    left: 18px;
    z-index: 100;
    padding: 10px 14px;
    border-radius: 6px;
    color: #fff;
    background: #111827;
}

.skip-link:focus {
    top: 10px;
}

.site-header {
    height: 72px;
    position: sticky;
    top: 0;
    z-index: 50;
    border-bottom: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(12px);
}

.header-inner {
    max-width: 1420px;
    height: 100%;
    margin: auto;
    padding: 0 22px;
    display: flex;
    align-items: center;
    gap: 38px;
}

.brand {
    width: 190px;
    display: flex;
    flex: 0 0 auto;
    flex-direction: column;
    line-height: 1;
}

.brand-cn {
    font-size: 20px;
    font-weight: 760;
    letter-spacing: -0.02em;
}

.brand-en {
    margin-top: 6px;
    color: #77808e;
    font-size: 9px;
    letter-spacing: 0.14em;
}

.main-nav {
    height: 100%;
    display: flex;
    align-items: stretch;
    gap: 3px;
}

.main-nav a {
    min-width: 66px;
    padding: 0 13px;
    display: grid;
    place-items: center;
    position: relative;
    color: #3e4653;
    font-size: 15px;
}

.main-nav a::after {
    content: "";
    position: absolute;
    right: 14px;
    bottom: 0;
    left: 14px;
    height: 3px;
    background: transparent;
}

.main-nav a:hover,
.main-nav a.active,
.main-nav a[aria-current="page"] {
    color: var(--blue);
}

.main-nav a.active::after,
.main-nav a[aria-current="page"]::after {
    background: var(--blue);
}

.header-actions {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 20px;
}

.search-trigger {
    padding: 0;
    border: 0;
    display: flex;
    align-items: center;
    gap: 8px;
    color: #505a69;
    background: transparent;
    font-size: 13px;
}

.search-icon {
    width: 15px;
    height: 15px;
    border: 2px solid currentColor;
    border-radius: 50%;
    position: relative;
}

.search-icon::after {
    content: "";
    width: 6px;
    height: 2px;
    position: absolute;
    right: -5px;
    bottom: -2px;
    background: currentColor;
    transform: rotate(45deg);
}

.contact-link {
    min-height: 36px;
    padding: 0 14px;
    border-radius: 6px;
    display: inline-flex;
    align-items: center;
    color: #fff;
    background: var(--blue);
    font-size: 13px;
    font-weight: 650;
}

.contact-link:hover {
    background: var(--blue-dark);
}

.menu-toggle {
    width: 40px;
    height: 40px;
    padding: 9px;
    border: 0;
    display: none;
    background: transparent;
    cursor: pointer;
}

.menu-toggle span {
    height: 1px;
    margin: 5px 0;
    display: block;
    background: var(--text);
    transition: transform 0.18s ease, opacity 0.18s ease;
}

.menu-toggle[aria-expanded="true"] span:first-child {
    transform: translateY(6px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.menu-toggle[aria-expanded="true"] span:last-child {
    transform: translateY(-6px) rotate(-45deg);
}

main {
    min-height: 75vh;
}

.page-wrap {
    max-width: 1420px;
    margin: auto;
    padding: 22px 22px 70px;
}

.surface-panel {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--surface);
    box-shadow: var(--shadow);
}

.breadcrumb {
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 9px;
    color: #707a89;
    font-size: 12px;
}

.breadcrumb a:hover {
    color: var(--blue);
}

.breadcrumb b {
    color: #505a68;
    font-weight: 500;
}

.section-kicker {
    margin: 0 0 9px;
    color: var(--blue);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.08em;
}

.shell-preview {
    min-height: 430px;
    padding: 48px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.shell-preview h1 {
    margin: 0;
    font-size: 36px;
    line-height: 1.25;
    letter-spacing: -0.04em;
}

.shell-preview > p:last-child {
    max-width: 720px;
    margin: 13px 0 0;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.75;
}

.site-footer {
    min-height: 120px;
    padding: 30px max(22px, calc((100vw - 1376px) / 2));
    border-top: 1px solid var(--line);
    display: grid;
    grid-template-columns: 1fr auto auto;
    align-items: center;
    gap: 50px;
    color: var(--muted);
    background: #fff;
}

.site-footer div {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.site-footer strong {
    color: var(--text);
    font-size: 15px;
}

.site-footer span,
.site-footer small,
.site-footer nav {
    font-size: 11px;
}

.site-footer nav {
    display: flex;
    gap: 20px;
}

.site-footer nav a:hover {
    color: var(--blue);
}

.site-footer .footer-legal {
    flex-direction: row;
    align-items: center;
    gap: 4px;
    font-size: 11px;
    white-space: nowrap;
}

.footer-legal a:hover {
    color: var(--blue);
}

@media (max-width: 1100px) {
    .header-inner {
        gap: 20px;
    }

    .brand {
        width: 170px;
    }

    .main-nav a {
        min-width: 56px;
        padding-inline: 9px;
        font-size: 14px;
    }
}

@media (max-width: 820px) {
    .site-header {
        height: 64px;
    }

    .header-inner {
        padding-inline: 16px;
        gap: 12px;
    }

    .brand {
        width: auto;
        margin-right: auto;
    }

    .brand-cn {
        font-size: 17px;
    }

    .header-actions .search-trigger span:last-child,
    .contact-link {
        display: none;
    }

    .search-trigger {
        width: 40px;
        height: 40px;
        justify-content: center;
    }

    .menu-toggle {
        display: block;
        order: 3;
    }

    .main-nav {
        height: auto;
        padding: 10px 16px 18px;
        border-bottom: 1px solid var(--line);
        position: fixed;
        top: 64px;
        right: 0;
        left: 0;
        display: none;
        grid-template-columns: repeat(3, 1fr);
        gap: 6px;
        background: #fff;
        box-shadow: 0 10px 20px rgba(20, 28, 42, 0.08);
    }

    .main-nav.open {
        display: grid;
    }

    .main-nav a {
        min-height: 40px;
        border-radius: 6px;
        background: #f7f8fa;
    }

    .main-nav a::after {
        display: none;
    }

    .page-wrap {
        padding: 16px 12px 50px;
    }

    .shell-preview {
        min-height: 390px;
        padding: 38px 30px;
    }
}

@media (max-width: 620px) {
    .page-wrap {
        padding-inline: 9px;
    }

    .shell-preview {
        min-height: 360px;
        padding: 30px 20px;
    }

    .shell-preview h1 {
        font-size: 30px;
    }

    .shell-preview > p:last-child {
        font-size: 14px;
    }

    .site-footer {
        padding: 28px 18px;
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .site-footer nav {
        flex-wrap: wrap;
    }

}

@media (max-width: 350px) {
    .brand-en {
        display: none;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        transition-duration: 0.01ms !important;
    }
}