/* ==========================================================================
   爱加速 — 页面样式（site.css）
   ========================================================================== */

/* ------------------------------ Header ------------------------------ */
.header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, .92);
    backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--border);
}

.nav-shell {
    display: flex;
    align-items: center;
    gap: 28px;
    min-height: var(--header-h);
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.0625rem;
    color: var(--text);
    letter-spacing: -.01em;
}

.brand img {
    width: 32px;
    height: 32px;
    border-radius: 8px;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 26px;
    margin-left: 12px;
    flex: 1;
}

.main-nav a {
    position: relative;
    color: var(--text-secondary);
    font-size: .9375rem;
    font-weight: 500;
    padding: 6px 0;
    transition: color .18s ease;
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
    color: var(--brand-600);
}

.main-nav a[aria-current="page"]::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -2px;
    height: 2px;
    border-radius: 2px;
    background: var(--brand-600);
}

.nav-download {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 9px 18px;
    border-radius: var(--radius-pill);
    background: var(--brand-600);
    color: #fff;
    font-size: .9375rem;
    font-weight: 600;
    box-shadow: var(--shadow-sm);
    transition: background .18s ease, transform .18s ease;
}

.nav-download:hover {
    background: var(--brand-700);
    color: #fff;
    transform: translateY(-1px);
}

.nav-menu {
    display: none;
    width: 40px;
    height: 40px;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text);
}

/* ------------------------------ Buttons ------------------------------ */
.action {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 22px;
    border-radius: var(--radius-md);
    background: var(--brand-600);
    color: #fff;
    font-weight: 600;
    font-size: .9375rem;
    box-shadow: var(--shadow-md);
    transition: background .18s ease, transform .18s ease, box-shadow .18s ease;
}

.action:hover {
    background: var(--brand-700);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.action.is-ghost {
    background: #fff;
    color: var(--brand-700);
    border: 1px solid var(--brand-200);
    box-shadow: none;
}

.action.is-ghost:hover {
    background: var(--brand-50);
    color: var(--brand-700);
}

.text-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-weight: 600;
    font-size: .9375rem;
}

/* ------------------------------ Hero ------------------------------ */
.hero {
    position: relative;
    overflow: hidden;
    background:
        radial-gradient(900px 420px at 88% -10%, var(--brand-50), transparent 70%),
        radial-gradient(700px 360px at 0% 110%, var(--accent-50), transparent 70%),
        var(--bg);
    padding: clamp(56px, 8vw, 96px) 0 clamp(48px, 7vw, 88px);
}

.hero-side {
    display: grid;
    grid-template-columns: 1.05fr .95fr;
    align-items: center;
    gap: clamp(32px, 5vw, 64px);
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 18px;
    padding: 6px 14px;
    border-radius: var(--radius-pill);
    background: #fff;
    border: 1px solid var(--brand-100);
    color: var(--brand-700);
    font-size: .8125rem;
    font-weight: 600;
    letter-spacing: .02em;
}

.eyebrow::before {
    content: "";
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent-500);
}

.hero-copy h1 {
    max-width: 20ch;
}

.hero-lede {
    margin-top: 18px;
    max-width: 46ch;
    color: var(--text-secondary);
    font-size: 1.0625rem;
}

.download-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin-top: 30px;
}

.platform {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 11px 20px;
    border-radius: var(--radius-md);
    background: #fff;
    border: 1px solid var(--border-strong);
    color: var(--text);
    font-weight: 600;
    font-size: .9375rem;
    box-shadow: var(--shadow-sm);
    transition: border-color .18s ease, transform .18s ease, box-shadow .18s ease;
}

.platform:hover {
    border-color: var(--brand-500);
    color: var(--brand-700);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.platform .os {
    font-size: .75rem;
    font-weight: 700;
    letter-spacing: .06em;
    text-transform: uppercase;
    color: var(--text-tertiary);
}

.platform .arrow {
    font-size: 1rem;
    color: var(--brand-600);
}

.hero-copy .text-link {
    margin-top: 22px;
}

.hero-photo {
    margin: 0;
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
}

.hero-photo img {
    width: 100%;
    height: auto;
}

.side-caption {
    margin-top: 12px;
    color: var(--text-tertiary);
    font-size: .8125rem;
    text-align: center;
}

/* ------------------------------ Section ------------------------------ */
section {
    scroll-margin-top: 84px;
}

.feature-main {
    padding: var(--section-y) 0;
}

.section-intro {
    max-width: 700px;
    margin-bottom: 44px;
}

.kicker {
    display: block;
    margin-bottom: 12px;
    color: var(--brand-600);
    font-size: .8125rem;
    font-weight: 700;
    letter-spacing: .1em;
    text-transform: uppercase;
}

.section-intro p {
    margin-top: 14px;
    color: var(--text-secondary);
}

.feature-guide {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.feature-guide article {
    padding: 26px 24px;
    border-radius: var(--radius-lg);
    background: var(--bg-soft);
    border: 1px solid var(--border);
    transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}

.feature-guide article:hover {
    transform: translateY(-3px);
    border-color: var(--brand-200);
    box-shadow: var(--shadow-md);
}

.guide-line {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.guide-line .icon-box {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: #fff;
    border: 1px solid var(--brand-100);
    color: var(--brand-600);
    flex: none;
}

.guide-line h3 {
    margin: 0;
}

.feature-guide p {
    color: var(--text-secondary);
    font-size: .9375rem;
}

/* ------------------------------ Story ------------------------------ */
.story {
    padding: var(--section-y) 0;
    background: var(--bg-soft);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.story-inner {
    max-width: 760px;
    margin-inline: auto;
    text-align: center;
}

.story-head h2 {
    margin-bottom: 20px;
}

.story-body p {
    color: var(--text-secondary);
}

.story-body p + p {
    margin-top: 14px;
}

.story-body .text-link {
    margin-top: 24px;
}

/* ------------------------------ Proof ------------------------------ */
.proof {
    padding: 56px 0;
}

.proof-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
    margin-top: 28px;
}

.proof-item {
    padding: 22px 20px;
    border-radius: var(--radius-md);
    border: 1px dashed var(--border-strong);
    background: #fff;
    text-align: center;
}

.proof-item strong {
    display: block;
    color: var(--brand-700);
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -.02em;
}

.proof-item span {
    display: block;
    margin-top: 4px;
    color: var(--text-secondary);
    font-size: .875rem;
}

/* ------------------------------ Download CTA ------------------------------ */
.download-cta {
    padding: 0 0 var(--section-y);
}

.download-cta .cta-box {
    padding: clamp(32px, 5vw, 56px);
    border-radius: 24px;
    background:
        radial-gradient(600px 260px at 100% 0%, rgba(37, 99, 235, .2), transparent 65%),
        linear-gradient(135deg, #0f172a, #1e3a8a);
    color: #fff;
    text-align: center;
}

.download-cta h2 {
    color: #fff;
}

.download-cta p {
    margin-top: 14px;
    color: rgba(255, 255, 255, .78);
}

.download-cta .download-actions {
    justify-content: center;
}

.download-cta .platform {
    background: rgba(255, 255, 255, .1);
    border-color: rgba(255, 255, 255, .28);
    color: #fff;
}

.download-cta .platform:hover {
    background: rgba(255, 255, 255, .18);
    border-color: rgba(255, 255, 255, .6);
    color: #fff;
}

.download-cta .platform .os {
    color: rgba(255, 255, 255, .7);
}

.download-cta .platform .arrow {
    color: #fff;
}

/* ------------------------------ Sub page ------------------------------ */
.page-head {
    padding: clamp(48px, 7vw, 72px) 0 40px;
    background: var(--bg-soft);
    border-bottom: 1px solid var(--border);
}

.page-head h1 {
    max-width: 26ch;
}

.page-head p {
    margin-top: 16px;
    max-width: 62ch;
    color: var(--text-secondary);
}

.page-body {
    padding: var(--section-y) 0;
}

.stack {
    display: grid;
    gap: 24px;
}

.block {
    padding: 28px;
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
}

.block h2 {
    font-size: 1.375rem;
    margin-bottom: 12px;
}

.block h3 {
    margin-top: 20px;
    margin-bottom: 6px;
}

.block p {
    color: var(--text-secondary);
}

.checklist {
    display: grid;
    gap: 10px;
    margin-top: 18px;
}

.checklist li {
    position: relative;
    padding-left: 26px;
    color: var(--text-secondary);
}

.checklist li::before {
    content: "";
    position: absolute;
    left: 0;
    top: .55em;
    width: 14px;
    height: 8px;
    border-left: 2px solid var(--accent-600);
    border-bottom: 2px solid var(--accent-600);
    transform: rotate(-45deg);
}

.steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 24px;
}

.steps li {
    padding: 22px;
    border-radius: var(--radius-md);
    background: var(--bg-soft);
    border: 1px solid var(--border);
}

.steps .num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 26px;
    margin-bottom: 10px;
    border-radius: 50%;
    background: var(--brand-600);
    color: #fff;
    font-size: .8125rem;
    font-weight: 700;
}

.steps h3 {
    margin: 0 0 6px;
}

.steps p {
    font-size: .9375rem;
    color: var(--text-secondary);
}

/* FAQ 手风琴（原生 details） */
.faq-list {
    display: grid;
    gap: 12px;
    max-width: 860px;
}

.faq-list details {
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: #fff;
    padding: 16px 20px;
}

.faq-list summary {
    cursor: pointer;
    font-weight: 600;
    color: var(--text);
    list-style: none;
}

.faq-list summary::-webkit-details-marker {
    display: none;
}

.faq-list summary::after {
    content: "+";
    float: right;
    color: var(--brand-600);
    font-weight: 700;
}

.faq-list details[open] summary::after {
    content: "−";
}

.faq-list details p {
    margin-top: 10px;
    color: var(--text-secondary);
    font-size: .9375rem;
}

/* ------------------------------ Footer ------------------------------ */
.footer {
    background: #0f172a;
    color: rgba(255, 255, 255, .7);
    padding: 56px 0 32px;
}

.footer-inner {
    display: grid;
    gap: 28px;
}

.footer-brand {
    font-size: 1.125rem;
    font-weight: 700;
    color: #fff;
}

.footer p {
    max-width: 52ch;
    margin-top: 10px;
    font-size: .9375rem;
    color: rgba(255, 255, 255, .62);
}

.footer-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 22px;
    padding-top: 22px;
    border-top: 1px solid rgba(255, 255, 255, .12);
}

.footer-nav a {
    color: rgba(255, 255, 255, .78);
    font-size: .9375rem;
}

.footer-nav a:hover {
    color: #fff;
}

.footer small {
    display: block;
    color: rgba(255, 255, 255, .45);
    font-size: .8125rem;
}

/* ------------------------------ Responsive ------------------------------ */
@media (max-width: 1023px) {
    .feature-guide {
        grid-template-columns: repeat(2, 1fr);
    }

    .proof-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .hero-side {
        gap: 32px;
    }

    .steps {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 767px) {
    .nav-menu {
        display: inline-flex;
    }

    .nav-shell {
        gap: 12px;
    }

    .nav-download {
        display: none;
    }

    .main-nav {
        position: absolute;
        left: 0;
        right: 0;
        top: var(--header-h);
        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        margin: 0;
        padding: 8px 18px 18px;
        background: #fff;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-md);
    }

    .main-nav.is-open {
        display: flex;
    }

    .main-nav a {
        padding: 12px 0;
        border-bottom: 1px solid var(--border);
    }

    .main-nav a:last-child {
        border-bottom: 0;
    }

    .main-nav a[aria-current="page"]::after {
        display: none;
    }

    .brand {
        margin-right: auto;
    }

    .hero-side {
        grid-template-columns: 1fr;
    }

    .hero-copy h1 {
        max-width: 100%;
    }

    .hero-photo {
        order: 2;
    }

    .feature-guide {
        grid-template-columns: 1fr;
    }

    .proof-grid {
        grid-template-columns: 1fr;
    }

    .download-actions {
        gap: 10px;
    }

    .platform {
        flex: 1 1 100%;
        justify-content: center;
    }

    .block {
        padding: 22px;
    }
}

@media (max-width: 375px) {
    h1 {
        font-size: 1.75rem;
    }

    .container {
        padding-inline: 16px;
    }
}

/* ------------------------------ News / Article ------------------------------ */
.page-head h1 {
    max-width: 34ch;
}

.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    margin-bottom: 18px;
    font-size: .8125rem;
    color: var(--text-tertiary);
}

.breadcrumb a {
    color: var(--text-secondary);
}

.breadcrumb a:hover {
    color: var(--brand-600);
}

.breadcrumb span[aria-current="page"] {
    color: var(--text-tertiary);
}

.page-lede {
    font-size: 1.0625rem;
    line-height: 1.75;
}

.article-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 20px;
    margin-top: 20px;
    font-size: .8125rem;
    color: var(--text-tertiary);
}

.article-meta span + span::before {
    content: "·";
    margin-right: 20px;
    color: var(--border-strong);
}

.article-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: 48px;
    align-items: start;
}

.article-body {
    max-width: 68ch;
}

.article-body h2 {
    margin-top: 40px;
    margin-bottom: 14px;
    font-size: 1.375rem;
    line-height: 1.45;
}

.article-body h2:first-child {
    margin-top: 0;
}

.article-body p {
    margin-bottom: 16px;
    line-height: 1.9;
    color: var(--text-secondary);
}

.article-body .article-intro {
    padding-left: 18px;
    border-left: 3px solid var(--brand-200);
    color: var(--text);
    font-size: 1.0625rem;
}

.article-body ul {
    display: grid;
    gap: 8px;
    margin: 0 0 20px;
    padding-left: 0;
    list-style: none;
}

.article-body li {
    position: relative;
    padding-left: 20px;
    line-height: 1.8;
    color: var(--text-secondary);
}

.article-body li::before {
    content: "";
    position: absolute;
    left: 2px;
    top: .78em;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--brand-500);
}

.article-side {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    display: grid;
    gap: 20px;
}

.related-list {
    display: grid;
    gap: 12px;
    margin-top: 16px;
}

.related-list a {
    display: block;
    font-size: .9375rem;
    line-height: 1.6;
    color: var(--text-secondary);
}

.related-list a:hover {
    color: var(--brand-600);
}

.article-side .side-caption {
    margin-top: 14px;
    font-size: .8125rem;
    color: var(--text-tertiary);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
}

.news-card {
    display: flex;
    flex-direction: column;
    padding: 26px;
    border-radius: var(--radius-lg);
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}

.news-card:hover {
    transform: translateY(-2px);
    border-color: var(--brand-200);
    box-shadow: var(--shadow-md);
}

.news-card h2 {
    margin: 14px 0 10px;
    font-size: 1.125rem;
    line-height: 1.55;
}

.news-card h2 a {
    color: var(--text);
}

.news-card h2 a:hover {
    color: var(--brand-600);
}

.news-card p {
    margin-bottom: 18px;
    font-size: .9375rem;
    line-height: 1.75;
    color: var(--text-secondary);
}

.news-card .text-link {
    margin-top: auto;
    font-size: .875rem;
}

.news-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    font-size: .75rem;
    color: var(--text-tertiary);
}

.tag-pill {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    border-radius: var(--radius-pill);
    background: var(--brand-50);
    color: var(--brand-600);
    font-weight: 600;
}

@media (max-width: 1024px) {
    .news-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .article-layout {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .article-side {
        position: static;
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 720px) {
    .news-grid {
        grid-template-columns: 1fr;
    }

    .article-side {
        grid-template-columns: 1fr;
    }

    .article-meta span + span::before {
        margin-right: 10px;
    }

    .article-meta {
        gap: 6px 12px;
    }
}