/* 官网首页专属样式（共用的变量、顶栏、页脚、按钮在 site.css） */

.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

.landing { overflow-x: clip; }
.landing .icon { stroke-width: 1.6; }

/* ---------- 示意图占位 ---------- */
.shot { margin: 0; }
.shot figcaption {
    margin: 16px auto 0;
    max-width: 44em;
    text-align: center;
    color: var(--muted);
    font-size: 14px;
    line-height: 1.6;
}
.mock { position: relative; width: 100%; }
.mock-hero-bank { aspect-ratio: 1040 / 650; }
.mock-editor { aspect-ratio: 1040 / 620; }
.mock-details { aspect-ratio: 1040 / 650; }
.mock-paper-editor { aspect-ratio: 1040 / 650; }
.mock-teach { aspect-ratio: 1040 / 585; }

/* ---------- 首屏 ---------- */
.hero {
    position: relative;
    padding: 72px 0 8px;
    text-align: center;
}
.hero::before,
.cta::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image: radial-gradient(var(--grid-dot) 1px, transparent 1.4px);
    background-size: 24px 24px;
    background-position: center top;
    pointer-events: none;
}
.hero::before {
    -webkit-mask-image: linear-gradient(#000 30%, transparent 85%);
    mask-image: linear-gradient(#000 30%, transparent 85%);
}
.cta::before {
    -webkit-mask-image: radial-gradient(ellipse 70% 80% at 50% 50%, #000 20%, transparent 85%);
    mask-image: radial-gradient(ellipse 70% 80% at 50% 50%, #000 20%, transparent 85%);
}
.hero > .wrap, .cta > .wrap { position: relative; }

.hero-text > * { animation: rise 0.8s cubic-bezier(0.2, 0.7, 0.2, 1) both; }
.hero-text > :nth-child(2) { animation-delay: 0.06s; }
.hero-text > :nth-child(3) { animation-delay: 0.12s; }
.hero-text > :nth-child(4) { animation-delay: 0.18s; }
.hero-text > :nth-child(5) { animation-delay: 0.24s; }
.hero-text > :nth-child(6) { animation-delay: 0.3s; }

.hero-kicker {
    display: inline-block;
    margin: 0 0 22px;
    padding: 4px 14px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: color-mix(in srgb, var(--bg) 80%, transparent);
    color: var(--muted);
    font-size: 13px;
}
.hero-title {
    margin: 0;
    font-size: clamp(44px, 7vw, 64px);
    font-weight: 600;
    letter-spacing: -0.03em;
    line-height: 1.1;
}
.hero-tag {
    margin: 6px 0 0;
    font-size: clamp(30px, 5vw, 48px);
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.2;
}
.hero-sub {
    margin: 22px auto 0;
    max-width: 38em;
    color: var(--muted);
    font-size: 16px;
    line-height: 1.75;
}

.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 14px 28px;
    margin-top: 34px;
    position: relative;
    z-index: 5;
}
.hero-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--muted);
    font-size: 15px;
}
.hero-link:hover { color: var(--text); text-decoration: none; }
.hero-link .icon { width: 16px; height: 16px; }

/* 分裂下载按钮 */
.split { display: inline-flex; align-items: stretch; height: 44px; }
.split-main, .split-menu summary {
    display: inline-flex;
    align-items: center;
    background: var(--primary);
    color: var(--primary-text);
    font-weight: 600;
    font-size: 16px;
    transition: background-color 0.2s ease;
}
.split-main {
    gap: 8px;
    padding: 0 20px 0 18px;
    border-radius: 12px 0 0 12px;
}
.split-main:hover, .split-menu summary:hover, .split-menu[open] summary {
    background: var(--primary-hover);
    text-decoration: none;
}
.split-menu { position: relative; display: flex; }
.split-menu summary {
    list-style: none;
    justify-content: center;
    width: 42px;
    border-radius: 0 12px 12px 0;
    border-left: 1px solid color-mix(in srgb, var(--primary-text) 28%, transparent);
    cursor: pointer;
}
.split-menu summary::-webkit-details-marker { display: none; }
.split-menu summary .icon { transition: transform 0.2s ease; }
.split-menu[open] summary .icon { transform: rotate(180deg); }
.split-pop {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    min-width: 188px;
    padding: 6px;
    text-align: left;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: 0 16px 40px -12px var(--shadow);
}
.split-pop a {
    display: block;
    padding: 9px 12px;
    border-radius: 8px;
    color: var(--text);
    font-size: 15px;
    white-space: nowrap;
}
.split-pop a:hover { background: var(--bg-alt); text-decoration: none; }

.ticks {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px 26px;
    margin: 22px 0 0;
    padding: 0;
    list-style: none;
    color: var(--muted);
    font-size: 14px;
}
.ticks li { display: inline-flex; align-items: center; gap: 6px; }
.ticks .icon { width: 16px; height: 16px; color: var(--ill-green); stroke-width: 2.2; }

.hero-shot { margin: 56px 0 0; }

/* ---------- 分区 ---------- */
.sec { padding: 104px 0 0; scroll-margin-top: 56px; }
.sec-alt { background: var(--bg-alt); margin-top: 104px; padding: 88px 0; border-block: 1px solid var(--border); }
.sec#faq { padding-bottom: 104px; }
.sec#faq + .sec-alt { margin-top: 0; }

.sec-no {
    margin: 0 0 14px;
    color: var(--muted);
    font-size: 12px;
    letter-spacing: 0.08em;
}
.sec-head {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: end;
    gap: 16px 64px;
    margin-bottom: 40px;
}
.landing h2 {
    margin: 0;
    font-size: clamp(28px, 4.2vw, 40px);
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.2;
}
.landing h2.center { text-align: center; }
.sec-lead {
    margin: 0;
    color: var(--muted);
    font-size: 16px;
    line-height: 1.7;
}

/* 2x2 功能卡片，1px 分隔线 */
.cards {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1px;
    background: var(--border);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
}
.card {
    background: var(--bg);
    padding: 28px 24px 30px;
}
.card-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    margin-bottom: 16px;
    border-radius: 10px;
    background: var(--accent-bg);
    color: var(--primary);
}
.card h3 { margin: 0 0 8px; font-size: 17px; font-weight: 600; }
.card p {
    margin: 0;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.7;
}
.card code, .tri-card code, .faq code { color: var(--text); }

.shot:not(.hero-shot) { margin: 44px 0 0; }
.shot-pair {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
    margin: 44px 0 0;
}
.shot-pair .shot { margin: 0; }

/* 步骤条 */
.steps {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px 36px;
    margin: 40px 0 0;
    padding: 0;
    list-style: none;
}
.steps li {
    position: relative;
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 16px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background: var(--surface);
    font-size: 15px;
    font-weight: 600;
}
.steps b {
    flex: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: var(--ink);
    color: var(--ink-text);
    font-size: 13px;
}
.steps li:not(:last-child)::after {
    content: "→";
    position: absolute;
    right: -26px;
    top: 50%;
    width: 16px;
    transform: translateY(-50%);
    text-align: center;
    color: var(--muted);
    font-weight: 400;
}

/* 统计数字带 */
.stats {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1px;
    margin: 56px 0 0;
    background: var(--border);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
}
.stat {
    padding: 28px 16px 26px;
    text-align: center;
    background: var(--bg);
}
.stat dt { display: flex; align-items: baseline; justify-content: center; gap: 6px; }
.stat dd { margin: 4px 0 0; color: var(--muted); font-size: 13px; }
.stat-num {
    font-size: 44px;
    font-weight: 600;
    line-height: 1.1;
    letter-spacing: -0.02em;
    font-variant-numeric: tabular-nums;
}
.stat-unit { font-size: 16px; font-weight: 600; }

/* ---------- 数据在本机 ---------- */
.tri {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
    margin-top: 44px;
}
.tri-card {
    padding: 26px 24px 28px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
}
.tri-card h3 { margin: 0 0 8px; font-size: 17px; font-weight: 600; }
.tri-card p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.7; }
.tri-card code { font-size: 0.84em; }

/* ---------- FAQ ---------- */
.faq { max-width: 820px; margin: 44px auto 0; border-top: 1px solid var(--border); }
.faq details { border-bottom: 1px solid var(--border); }
.faq summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 20px 4px;
    font-size: 17px;
    font-weight: 600;
    list-style: none;
    cursor: pointer;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
    content: "";
    flex: none;
    width: 14px;
    height: 14px;
    background:
        linear-gradient(var(--muted), var(--muted)) center / 100% 1.6px no-repeat,
        linear-gradient(var(--muted), var(--muted)) center / 1.6px 100% no-repeat;
    transition: transform 0.25s ease;
}
.faq details[open] summary::after { transform: rotate(135deg); }
.faq summary:hover { color: var(--primary); }
.faq details p {
    margin: 0;
    padding: 0 40px 22px 4px;
    color: var(--muted);
    font-size: 15px;
    line-height: 1.75;
}

/* ---------- 下载 ---------- */
.dl { text-align: center; }
.dl-lead { margin: 14px auto 0; max-width: 36em; color: var(--muted); }
.dl-actions {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 30px;
}
.dl-btn { min-height: 44px; padding: 0 26px; }
.dl-note { margin: 16px auto 0; max-width: 40em; color: var(--muted); font-size: 14px; }
.dl-actions + .dl-note { margin-top: 22px; }

/* ---------- 号召区 ---------- */
.cta {
    position: relative;
    padding: 104px 0 112px;
    text-align: center;
}
.cta-lead { margin: 14px auto 0; max-width: 34em; color: var(--muted); }
.cta-actions {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 30px;
}
.pill {
    display: inline-flex;
    align-items: center;
    height: 42px;
    padding: 0 22px;
    border: 1px solid transparent;
    border-radius: 999px;
    font-size: 15px;
    font-weight: 600;
    transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}
.pill:hover { text-decoration: none; }
.pill.solid { background: var(--ink); color: var(--ink-text); }
.pill.solid:hover { background: var(--ink-hover); }
.pill.outline { background: var(--bg); color: var(--text); border-color: var(--border); }
.pill.outline:hover { border-color: var(--muted); }
.pill.ghost { color: var(--muted); font-weight: 500; }
.pill.ghost:hover { color: var(--text); }

/* ---------- 页脚 ---------- */
.footer-rich { padding: 36px 0 28px; }
.footer-main {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 20px 40px;
}
.footer-brand .brand { font-size: 16px; }
.footer-brand .brand img { border-radius: 7px; }
.footer-brand p { margin: 6px 0 0; font-size: 13px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 24px; padding-top: 4px; }
.footer-links .quiet { margin-left: 0; opacity: 0.7; }
.footer-copy {
    margin: 28px 0 0;
    padding-top: 18px;
    border-top: 1px solid var(--border);
    font-size: 13px;
}

/* ---------- 渐显（site.js 加 js-reveal 后生效） ---------- */
.js-reveal .reveal-group.reveal { opacity: 1; transform: none; }
.js-reveal .steps.reveal-group > .reveal:nth-child(2) { transition-delay: 0.08s; }
.js-reveal .steps.reveal-group > .reveal:nth-child(3) { transition-delay: 0.16s; }
.js-reveal .steps.reveal-group > .reveal:nth-child(4) { transition-delay: 0.24s; }
.js-reveal .tri.reveal-group > .reveal:nth-child(2) { transition-delay: 0.08s; }
.js-reveal .tri.reveal-group > .reveal:nth-child(3) { transition-delay: 0.16s; }

/* ---------- 窄屏 ---------- */
@media (max-width: 900px) {
    .sec-head { grid-template-columns: minmax(0, 1fr); align-items: start; gap: 12px; margin-bottom: 32px; }
    .tri { grid-template-columns: minmax(0, 1fr); }
    .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
    .steps li::after { display: none; }
}

@media (max-width: 759px) {
    .wrap { padding: 0 18px; }
    .hero { padding: 44px 0 48px; }
    .hero-shot { margin-top: 44px; }
    .sec { padding-top: 72px; }
    .sec-alt { margin-top: 72px; padding: 64px 0; }
    .sec#faq { padding-bottom: 72px; }
    .cta { padding: 72px 0 80px; }
    .cards { grid-template-columns: minmax(0, 1fr); }
    .shot-pair { grid-template-columns: minmax(0, 1fr); gap: 36px; }
    .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .stat-num { font-size: 36px; }
    .split { height: 46px; }
    .hero-actions { flex-direction: column; gap: 16px; }
    .faq summary { font-size: 16px; }
    .faq details p { padding-right: 8px; }
}

@media (max-width: 420px) {
    .steps li { padding: 12px; gap: 10px; font-size: 14px; }
}

.footer-brand .brand { color: var(--text); }