/* home.css — ZeroA11y 零障
   方向：清晰地平线 · 品牌优先 · 首屏克制 · 自身即无障碍示范 */

:root {
    --ink: #0c1222;
    --ink-2: #2a3548;
    --muted: #5c6b7e;
    --paper: #f4f6f8;
    --paper-2: #e8edf2;
    --line: #d5dde6;
    --brand: #0f6e7a;
    --brand-deep: #0a525b;
    --brand-soft: #d7eef1;
    --sand: #f0ebe3;
    --warm: #b45309;
    --hero-fg: #f7fafc;
    --radius: 10px;
    --font-sans: "Noto Sans SC", "DM Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-latin: "DM Sans", "Noto Sans SC", sans-serif;
    /* 标题衬线：仅用于品牌与各级标题，正文保持无衬线 */
    --font-display: "Noto Serif SC", "Songti SC", "Noto Sans SC", serif;
    --font-ui: var(--font-sans);
    --ease: cubic-bezier(.22, 1, .36, 1);
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: var(--font-sans);
    color: var(--ink);
    background: var(--paper);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* 压过 Bootstrap Reboot：正文/控件统一无衬线 */
body, button, input, select, textarea,
.btn, .form-control, .form-select, .nav-link {
    font-family: var(--font-sans);
}

/* 标题与品牌字标：衬线（你喜欢的那套气质） */
.navbar-brand,
.hero-brand,
.hero-title,
.section-head h2,
.proof-grid .num,
.cap-body h3,
.overseas h2,
.ov-grid h3,
.case-row h3,
.link-cell h3,
.site-footer h4,
h1, h2, h3, h4 {
    font-family: var(--font-display);
}

/* 英文小标签 / 序号：拉丁无衬线 */
.brand-en,
.section-kicker,
.cap-en,
.cap-index,
.hero-brand .brand-en,
.link-cell .meta {
    font-family: var(--font-latin);
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--brand-deep); }
a:hover { color: var(--brand); }

:focus-visible {
    outline: 3px solid var(--brand);
    outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: .01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: .01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ===== Skip ===== */
.skip-link {
    position: absolute;
    top: -80px;
    left: 16px;
    z-index: 3000;
    background: var(--brand);
    color: #fff;
    padding: 12px 20px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
}
.skip-link:focus { top: 16px; color: #fff; }

/* ===== Header ===== */
.site-header {
    position: fixed;
    inset: 0 0 auto;
    z-index: 1030;
    transition: background .35s var(--ease), border-color .35s var(--ease), backdrop-filter .35s;
    border-bottom: 1px solid transparent;
}
.site-header.is-solid {
    background: rgba(244, 246, 248, .92);
    backdrop-filter: blur(12px);
    border-bottom-color: var(--line);
}
.site-header .navbar { padding: .85rem 0; }
.site-header .navbar-brand {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.15rem;
    color: var(--hero-fg);
    letter-spacing: .02em;
    text-decoration: none;
}
.site-header.is-solid .navbar-brand { color: var(--ink); }
.site-header .navbar-brand .brand-en {
    font-family: var(--font-ui);
    font-weight: 600;
    font-size: .72em;
    letter-spacing: .08em;
    opacity: .85;
    margin-right: .35rem;
}
.site-header .nav-link {
    color: rgba(247, 250, 252, .88);
    font-weight: 500;
    font-size: .92rem;
    padding: .45rem .75rem !important;
}
.site-header.is-solid .nav-link { color: var(--ink-2); }
.site-header .nav-link:hover,
.site-header .nav-link:focus-visible {
    color: #fff;
}
.site-header.is-solid .nav-link:hover,
.site-header.is-solid .nav-link:focus-visible {
    color: var(--brand-deep);
}
.nav-cta {
    border: 1px solid rgba(255, 255, 255, .45) !important;
    color: #fff !important;
    padding: .45rem 1rem !important;
    border-radius: 999px;
    margin-left: .35rem;
}
.site-header.is-solid .nav-cta {
    background: var(--brand) !important;
    border-color: var(--brand) !important;
    color: #fff !important;
}
.nav-cta:hover, .nav-cta:focus-visible {
    background: rgba(255, 255, 255, .14) !important;
    color: #fff !important;
}
.site-header.is-solid .nav-cta:hover {
    background: var(--brand-deep) !important;
}
.navbar-toggler {
    border-color: rgba(255, 255, 255, .5);
}
.navbar-toggler-icon {
    filter: invert(1);
}
.site-header.is-solid .navbar-toggler { border-color: var(--line); }
.site-header.is-solid .navbar-toggler-icon { filter: none; }
@media (max-width: 991.98px) {
    .site-header .navbar-collapse {
        background: rgba(12, 18, 34, .96);
        margin-top: .75rem;
        padding: 1rem;
        border-radius: 12px;
    }
    .site-header.is-solid .navbar-collapse {
        background: #fff;
        border: 1px solid var(--line);
    }
}

/* ===== Hero：全幅一构图 ===== */
.hero {
    position: relative;
    min-height: 100svh;
    display: flex;
    align-items: flex-end;
    color: var(--hero-fg);
    overflow: hidden;
    isolation: isolate;
}
.hero-media {
    position: absolute;
    inset: 0;
    z-index: -2;
}
.hero-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 35%;
    transform: scale(1.06);
    animation: heroken 28s var(--ease) both;
}
@keyframes heroken {
    from { transform: scale(1.06); }
    to { transform: scale(1); }
}
.hero-shade {
    position: absolute;
    inset: 0;
    z-index: -1;
    background:
        linear-gradient(180deg, rgba(12, 18, 34, .62) 0%, rgba(12, 18, 34, .45) 38%, rgba(12, 18, 34, .88) 100%),
        linear-gradient(90deg, rgba(12, 18, 34, .5) 0%, transparent 60%);
}
.hero-inner {
    width: 100%;
    padding: 6.5rem 0 4rem;
}
.hero-brand {
    font-family: var(--font-display);
    font-size: clamp(2.8rem, 9vw, 5.5rem);
    font-weight: 700;
    line-height: 1.05;
    letter-spacing: .04em;
    margin: 0 0 .6rem;
    animation: rise .9s var(--ease) both;
}
.hero-brand .brand-en {
    display: block;
    font-family: var(--font-ui);
    font-size: .22em;
    font-weight: 600;
    letter-spacing: .28em;
    text-transform: uppercase;
    opacity: .8;
    margin-bottom: .35rem;
}
.hero-title {
    font-family: var(--font-display);
    font-size: clamp(1.55rem, 3.4vw, 2.35rem);
    font-weight: 600;
    line-height: 1.35;
    max-width: 16em;
    margin: 0 0 1rem;
    animation: rise .9s var(--ease) .12s both;
}
.hero-sub {
    font-size: clamp(1rem, 1.5vw, 1.15rem);
    max-width: 34rem;
    opacity: .9;
    margin: 0 0 1.75rem;
    font-weight: 400;
    animation: rise .9s var(--ease) .22s both;
}
.hero-cta {
    display: flex;
    flex-wrap: wrap;
    gap: .75rem 1rem;
    align-items: stretch;
    max-width: 40rem;
    animation: rise .9s var(--ease) .32s both;
}
.hero-cta label {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}
.hero-cta .url-field {
    flex: 1 1 16rem;
    min-width: 0;
    background: rgba(255, 255, 255, .1);
    border: 1px solid rgba(255, 255, 255, .35);
    border-radius: 999px;
    color: #fff;
    padding: .95rem 1.25rem;
    font-size: 1rem;
    font-family: var(--font-ui);
}
.hero-cta .url-field::placeholder { color: rgba(255, 255, 255, .62); }
.hero-cta .url-field:focus {
    outline: 3px solid #7dd3de;
    outline-offset: 2px;
    background: rgba(255, 255, 255, .16);
}
.hero-cta .btn-detect {
    flex: 0 0 auto;
    background: #fff;
    color: var(--ink);
    border: none;
    border-radius: 999px;
    padding: .95rem 1.5rem;
    font-weight: 700;
    font-size: 1rem;
    font-family: var(--font-ui);
    cursor: pointer;
    transition: transform .25s var(--ease), background .25s;
}
.hero-cta .btn-detect:hover,
.hero-cta .btn-detect:focus-visible {
    background: var(--brand-soft);
    color: var(--brand-deep);
    transform: translateY(-1px);
}
.hero-cta-note {
    flex: 1 1 100%;
    margin: .15rem 0 0;
    font-size: .82rem;
    opacity: .72;
}
@keyframes rise {
    from { opacity: 0; transform: translateY(22px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== 通用区块 ===== */
.section {
    padding: clamp(3.5rem, 8vw, 6rem) 0;
}
.section-sand { background: var(--sand); }
.section-paper { background: var(--paper); }
.section-head {
    max-width: 40rem;
    margin-bottom: 2.5rem;
}
.section-head h2 {
    font-family: var(--font-display);
    font-size: clamp(1.65rem, 3vw, 2.2rem);
    font-weight: 700;
    line-height: 1.3;
    margin: 0 0 .65rem;
    letter-spacing: .01em;
}
.section-head p {
    margin: 0;
    color: var(--muted);
    font-size: 1.05rem;
}

.reveal {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity .7s var(--ease), transform .7s var(--ease);
}
.reveal.is-in {
    opacity: 1;
    transform: none;
}

/* ===== 信任数字（首屏外） ===== */
.proof {
    background: var(--ink);
    color: var(--hero-fg);
    padding: 2.25rem 0;
}
.proof-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
    text-align: left;
}
.proof-grid .num {
    font-family: var(--font-display);
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    font-weight: 700;
    color: #9fd8df;
    line-height: 1.1;
}
.proof-grid .lbl {
    font-size: .88rem;
    opacity: .75;
    margin-top: .25rem;
}
@media (max-width: 767px) {
    .proof-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ===== 标准条：安静文字，不做胶囊堆 ===== */
.standards {
    padding: 1.35rem 0;
    border-bottom: 1px solid var(--line);
    background: #fff;
    color: var(--muted);
    font-size: .92rem;
    letter-spacing: .02em;
}
.standards span + span::before {
    content: "·";
    margin: 0 .65rem;
    opacity: .45;
}

/* ===== 五形态：编辑式序号轨道（非图标卡片） ===== */
.section-capabilities {
    background:
        linear-gradient(180deg, #eef3f5 0%, var(--paper) 100%);
    position: relative;
}
.section-capabilities::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--brand) 0%, transparent 55%);
}
.section-kicker {
    font-family: var(--font-latin);
    font-size: .78rem;
    font-weight: 600;
    letter-spacing: .22em;
    text-transform: uppercase;
    color: var(--brand-deep);
    margin: 0 0 .75rem;
}
.cap-rail {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 1px;
    background: var(--line);
    border: 1px solid var(--line);
}
.cap-item {
    background: rgba(255, 255, 255, .88);
    padding: 1.65rem 1.25rem 1.85rem;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 1.1rem;
    min-height: 100%;
    transition: background .35s var(--ease), transform .35s var(--ease);
}
.cap-item:hover,
.cap-item:focus-within {
    background: #fff;
    transform: translateY(-3px);
    position: relative;
    z-index: 1;
    box-shadow: 0 18px 40px -28px rgba(12, 18, 34, .35);
}
.cap-index {
    font-family: var(--font-latin);
    font-size: .95rem;
    font-weight: 700;
    letter-spacing: .12em;
    color: var(--brand);
    opacity: .85;
}
.cap-en {
    margin: 0 0 .2rem;
    font-family: var(--font-latin);
    font-size: .72rem;
    font-weight: 600;
    letter-spacing: .16em;
    text-transform: uppercase;
    color: var(--muted);
}
.cap-body h3 {
    font-family: var(--font-display);
    font-size: 1.35rem;
    font-weight: 700;
    margin: 0 0 .55rem;
    letter-spacing: .02em;
}
.cap-body p:last-child {
    margin: 0;
    color: var(--ink-2);
    font-size: .92rem;
    line-height: 1.65;
}
@media (max-width: 991px) {
    .cap-rail {
        grid-template-columns: repeat(6, minmax(0, 1fr));
    }
    .cap-item { grid-column: span 2; }
    .cap-item:nth-child(4),
    .cap-item:nth-child(5) { grid-column: span 3; }
}
@media (max-width: 575px) {
    .cap-rail { grid-template-columns: 1fr; }
    .cap-item,
    .cap-item:nth-child(4),
    .cap-item:nth-child(5) { grid-column: auto; }
    .cap-item {
        flex-direction: row;
        align-items: flex-start;
        gap: 1rem;
        padding: 1.35rem 1.15rem;
    }
    .cap-index { padding-top: .2rem; min-width: 2rem; }
}

/* ===== 出海：全幅图像叙事 ===== */
.overseas {
    position: relative;
    color: var(--hero-fg);
    overflow: hidden;
    min-height: 28rem;
}
.overseas-media {
    position: absolute;
    inset: 0;
    z-index: 0;
}
.overseas-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.overseas-shade {
    position: absolute;
    inset: 0;
    background: linear-gradient(105deg, rgba(12, 18, 34, .92) 0%, rgba(12, 18, 34, .72) 48%, rgba(15, 110, 122, .45) 100%);
}
.overseas-inner {
    position: relative;
    z-index: 1;
    padding: clamp(3.5rem, 8vw, 5.5rem) 0;
}
.overseas h2 {
    font-family: var(--font-display);
    font-size: clamp(1.7rem, 3vw, 2.3rem);
    font-weight: 700;
    max-width: 16em;
    margin: 0 0 1rem;
}
.overseas .lead {
    max-width: 34rem;
    opacity: .9;
    margin-bottom: 2rem;
}
.ov-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.25rem 2rem;
    max-width: 44rem;
}
.ov-grid h3 {
    font-family: var(--font-display);
    font-size: 1.05rem;
    font-weight: 700;
    margin: 0 0 .3rem;
}
.ov-grid p {
    margin: 0;
    font-size: .9rem;
    opacity: .82;
}
@media (max-width: 575px) {
    .ov-grid { grid-template-columns: 1fr; }
}

/* ===== 案例：编辑式列表 ===== */
.case-list {
    display: grid;
    gap: 0;
    border-top: 1px solid var(--line);
}
.case-row {
    display: grid;
    grid-template-columns: 8.5rem 1fr;
    gap: 1.5rem;
    padding: 1.75rem 0;
    border-bottom: 1px solid var(--line);
}
.case-row .tag {
    font-size: .8rem;
    font-weight: 600;
    letter-spacing: .04em;
    color: var(--brand-deep);
    text-transform: none;
    padding-top: .2rem;
}
.case-row h3 {
    font-family: var(--font-display);
    font-size: 1.2rem;
    font-weight: 700;
    margin: 0 0 .4rem;
}
.case-row p { margin: 0; color: var(--ink-2); }
.case-row .result {
    margin-top: .55rem;
    color: var(--brand-deep);
    font-weight: 600;
    font-size: .92rem;
}
@media (max-width: 575px) {
    .case-row { grid-template-columns: 1fr; gap: .4rem; }
}

/* ===== 工具 / 知识：交互容器，轻边界 ===== */
.link-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--line);
    border: 1px solid var(--line);
}
.link-cell {
    background: #fff;
    padding: 1.5rem 1.35rem;
    display: flex;
    flex-direction: column;
    min-height: 100%;
    text-decoration: none;
    color: inherit;
    transition: background .25s var(--ease);
}
.link-cell:hover,
.link-cell:focus-visible {
    background: var(--brand-soft);
    color: inherit;
}
.link-cell h3 {
    font-family: var(--font-display);
    font-size: 1.08rem;
    font-weight: 700;
    margin: 0 0 .45rem;
    color: var(--ink);
}
.link-cell p {
    margin: 0;
    color: var(--muted);
    font-size: .9rem;
    flex: 1;
}
.link-cell .meta {
    margin-top: 1rem;
    font-size: .8rem;
    font-weight: 600;
    color: var(--brand-deep);
    letter-spacing: .04em;
}
@media (max-width: 991px) {
    .link-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 575px) {
    .link-grid { grid-template-columns: 1fr; }
}

/* ===== 联系表单（交互容器） ===== */
.contact-panel {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: clamp(1.5rem, 4vw, 2.25rem);
    max-width: 720px;
    margin: 0 auto;
}
.form-label { font-weight: 600; color: var(--ink-2); }
.form-control-enhanced,
.form-select {
    border-color: var(--line);
    padding: .7rem .9rem;
    border-radius: 8px;
    font-family: var(--font-ui);
}
.form-control-enhanced:focus,
.form-select:focus {
    border-color: var(--brand);
    box-shadow: 0 0 0 3px rgba(15, 110, 122, .2);
}
.required-field { color: #b91c1c; }
.optional-field { color: var(--muted); font-size: .85em; font-weight: 400; }
.honeypot-field {
    position: absolute;
    left: -9999px;
    top: -9999px;
    height: 0;
    overflow: hidden;
}
#submit.btn-primary,
.btn-send {
    background: var(--brand) !important;
    border-color: var(--brand) !important;
    font-weight: 700;
    padding: .85rem 1.25rem;
    border-radius: 999px;
}
#submit.btn-primary:hover,
.btn-send:hover {
    background: var(--brand-deep) !important;
    border-color: var(--brand-deep) !important;
}
.result-message p { margin: 12px 0 0; padding: 12px 16px; border-radius: 8px; }
.result-message p.success { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }
.result-message p.error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }

/* ===== Footer ===== */
.site-footer {
    background: var(--ink);
    color: #9aa8b8;
    padding: 3.5rem 0 1.75rem;
}
.site-footer h4 {
    color: #fff;
    font-family: var(--font-display);
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 1rem;
}
.site-footer a { color: #c5d0db; text-decoration: none; }
.site-footer a:hover,
.site-footer a:focus-visible { color: #fff; text-decoration: underline; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer ul li { margin-bottom: .55rem; font-size: .9rem; }
.footer-bottom {
    border-top: 1px solid #243044;
    margin-top: 2rem;
    padding-top: 1.15rem;
    font-size: .82rem;
    display: flex;
    flex-wrap: wrap;
    gap: .5rem 1.25rem;
    justify-content: space-between;
}
.footer-bottom .beian { color: #7a8899; }

/* 子页：固定实心顶栏，避免透明导航压在浅色内容上 */
body.subpage {
    padding-top: 4.75rem;
    --primary-color: #0f6e7a;
    --primary-dark: #0a525b;
    --primary-light: #3d8b94;
    --accent-color: #0f6e7a;
    --tester-primary: #0f6e7a;
    --tester-primary-hover: #0a525b;
    --tester-primary-light: #d7eef1;
}
body.subpage .site-header,
body.subpage .site-header.is-solid {
    background: rgba(244, 246, 248, .96);
    backdrop-filter: blur(12px);
    border-bottom-color: var(--line);
}
body.subpage .site-header .navbar-brand,
body.subpage .site-header.is-solid .navbar-brand { color: var(--ink); }
body.subpage .site-header .nav-link,
body.subpage .site-header.is-solid .nav-link { color: var(--ink-2); }
body.subpage .site-header .nav-link:hover,
body.subpage .site-header .nav-link:focus-visible,
body.subpage .site-header.is-solid .nav-link:hover,
body.subpage .site-header.is-solid .nav-link:focus-visible { color: var(--brand-deep); }
body.subpage .nav-cta,
body.subpage .site-header.is-solid .nav-cta {
    background: var(--brand) !important;
    border-color: var(--brand) !important;
    color: #fff !important;
}
body.subpage .navbar-toggler { border-color: var(--line); }
body.subpage .navbar-toggler-icon { filter: none; }
body.subpage .topHome { display: none !important; }
body.subpage .btn-primary {
    background-color: var(--brand);
    border-color: var(--brand);
}
body.subpage .btn-primary:hover,
body.subpage .btn-primary:focus-visible {
    background-color: var(--brand-deep);
    border-color: var(--brand-deep);
}

.cap-more {
    margin: .65rem 0 0;
    font-size: .88rem;
    font-weight: 600;
    font-family: var(--font-sans);
    color: var(--brand-deep);
    text-decoration: none;
}
.cap-more:hover,
.cap-more:focus-visible { text-decoration: underline; }

.back-top {
    position: fixed;
    left: 1.25rem;
    right: auto;
    bottom: 1.25rem;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--brand);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    z-index: 1020;
    opacity: 0;
    pointer-events: none;
    transform: translateY(8px);
    transition: opacity .3s, transform .3s;
}
@media (max-width: 576px) {
    .back-top {
        left: 12px;
        bottom: 12px;
    }
}
.back-top.is-show {
    opacity: 1;
    pointer-events: auto;
    transform: none;
}
.back-top:hover,
.back-top:focus-visible {
    background: var(--brand-deep);
    color: #fff;
}