/* SEO Studio 官网样式 —— 单文件、无外部依赖、深浅色自适应 */

:root {
    --bg: #ffffff;
    --bg-soft: #f6f8fb;
    --bg-dark: #0b1220;
    --fg: #0f172a;
    --fg-soft: #475569;
    --muted: #6b7280;
    --line: #e5e9f0;
    --line-strong: #cbd5e1;
    --brand: #2563eb;
    --brand-dark: #1d4ed8;
    --brand-soft: #eff6ff;
    --ok: #059669;
    --ok-soft: #ecfdf5;
    --warn: #b45309;
    --warn-soft: #fffbeb;
    --danger: #dc2626;
    --danger-soft: #fef2f2;
    --radius: 14px;
    --radius-sm: 9px;
    --shadow: 0 1px 2px rgba(15, 23, 42, .06), 0 8px 24px -12px rgba(15, 23, 42, .18);
    --shadow-lg: 0 24px 60px -24px rgba(15, 23, 42, .35);
    --mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    background: var(--bg);
    color: var(--fg);
    font: 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei UI", "PingFang SC", "Hiragino Sans GB", sans-serif;
    -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
h1, h2, h3, h4 { line-height: 1.28; margin: 0 0 .5em; font-weight: 700; letter-spacing: -.01em; }
h1 { font-size: clamp(30px, 4.4vw, 52px); }
h2 { font-size: clamp(23px, 2.8vw, 34px); }
h3 { font-size: 19px; }
p { margin: 0 0 1em; }
ul, ol { margin: 0 0 1em; padding-left: 1.35em; }
code, pre { font-family: var(--mono); }

.wrap { width: min(1160px, 100% - 40px); margin: 0 auto; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.center { text-align: center; }
.nowrap { white-space: nowrap; }
.hidden { display: none !important; }

/* ───────────────────────── 头部 ───────────────────────── */

.site-header {
    position: sticky; top: 0; z-index: 40;
    background: rgba(255, 255, 255, .88);
    backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; gap: 18px; min-height: 66px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--fg); font-weight: 700; }
.brand-mark {
    display: inline-grid; place-items: center; width: 34px; height: 34px;
    background: linear-gradient(135deg, var(--brand), #7c3aed);
    color: #fff; border-radius: 10px; font-size: 12px; letter-spacing: .5px;
}
.brand-text { font-size: 17px; }
.main-nav { display: flex; gap: 4px; margin-left: 8px; flex: 1; }
.main-nav a {
    padding: 8px 12px; border-radius: var(--radius-sm); color: var(--fg-soft);
    font-size: 15px; font-weight: 500; white-space: nowrap;
}
.main-nav a:hover { background: var(--bg-soft); color: var(--fg); }
.main-nav a.active { background: var(--brand-soft); color: var(--brand); }
.header-actions { display: flex; align-items: center; gap: 8px; }
.nav-toggle { display: none; background: none; border: 1px solid var(--line); border-radius: 8px; padding: 6px 10px; cursor: pointer; }
.lang-switch { display: inline-flex; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; }
.lang-switch a { padding: 5px 12px; font-size: 13px; color: var(--fg-soft); }
.lang-switch a.active { background: var(--brand); color: #fff; }

/* ───────────────────────── 按钮 ───────────────────────── */

.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 11px 20px; border-radius: var(--radius-sm); border: 1px solid transparent;
    font: inherit; font-weight: 600; cursor: pointer; transition: .16s ease;
    text-align: center;
}
.btn-sm { padding: 7px 14px; font-size: 14px; }
.btn-lg { padding: 14px 28px; font-size: 17px; }
.btn-primary { background: var(--brand); color: #fff; box-shadow: 0 8px 20px -10px rgba(37, 99, 235, .8); }
.btn-primary:hover { background: var(--brand-dark); color: #fff; transform: translateY(-1px); }
.btn-ghost { background: #fff; border-color: var(--line-strong); color: var(--fg); }
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }
.btn-dark { background: var(--bg-dark); color: #fff; }
.btn-dark:hover { background: #1e293b; color: #fff; }
.btn-block { width: 100%; }
.btn[disabled] { opacity: .55; cursor: not-allowed; transform: none; }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; }
.btn-row.center { justify-content: center; }

/* ───────────────────────── 通用块 ───────────────────────── */

section { padding: 66px 0; }
section.tight { padding: 40px 0; }
section.soft { background: var(--bg-soft); }
section.dark { background: var(--bg-dark); color: #e2e8f0; }
section.dark h1, section.dark h2, section.dark h3 { color: #fff; }
section.dark .muted { color: #94a3b8; }

.section-head { max-width: 760px; margin: 0 auto 40px; text-align: center; }
.section-head p { color: var(--muted); font-size: 17px; margin: 0; }

.card {
    background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
    padding: 24px; box-shadow: var(--shadow);
}
.card.flat { box-shadow: none; }
.card.pad-lg { padding: 30px; }

.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(268px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(228px, 1fr)); }

.pill {
    display: inline-block; padding: 4px 11px; border-radius: 999px;
    background: var(--brand-soft); color: var(--brand); font-size: 12.5px; font-weight: 600;
}
.pill.ok { background: var(--ok-soft); color: var(--ok); }
.pill.warn { background: var(--warn-soft); color: var(--warn); }
.pill.mono { font-family: var(--mono); }

.tick { color: var(--ok); font-weight: 700; }

/* ───────────────────────── 首页 Hero ───────────────────────── */

.hero {
    padding: 78px 0 66px;
    background:
        radial-gradient(1100px 460px at 12% -10%, #dbeafe 0%, transparent 62%),
        radial-gradient(900px 420px at 92% 0%, #ede9fe 0%, transparent 58%);
}
.hero-grid { display: grid; grid-template-columns: 1.08fr .92fr; gap: 46px; align-items: center; }
.hero h1 { margin-bottom: 18px; }
.hero-sub { font-size: 18px; color: var(--fg-soft); max-width: 560px; }
.hero-trust { display: flex; flex-wrap: wrap; gap: 10px 20px; margin-top: 22px; padding: 0; list-style: none; }
.hero-trust li { font-size: 13.5px; color: var(--muted); }
.hero-trust li::before { content: "✓"; color: var(--ok); font-weight: 700; margin-right: 6px; }

.hero-card {
    background: #fff; border: 1px solid var(--line); border-radius: 18px;
    padding: 22px; box-shadow: var(--shadow-lg);
}
.hero-card img { border-radius: 10px; border: 1px solid var(--line); display: block; }
.hero-card .caption { font-size: 12.5px; color: var(--muted); margin-top: 10px; text-align: center; }

/* ───────────────────────── 定价 ───────────────────────── */

.price-card { position: relative; display: flex; flex-direction: column; }
.price-card.featured { border-color: var(--brand); box-shadow: 0 0 0 3px rgba(37, 99, 235, .12), var(--shadow-lg); }
.price-card .badge {
    position: absolute; top: -13px; left: 24px; background: var(--brand); color: #fff;
    font-size: 12px; font-weight: 700; padding: 4px 12px; border-radius: 999px;
}
.price-amount { display: flex; align-items: baseline; gap: 8px; margin: 6px 0 4px; }
.price-amount .num { font-size: 40px; font-weight: 800; letter-spacing: -.02em; }
.price-amount .unit { color: var(--muted); font-size: 15px; }
.price-cny { color: var(--muted); font-size: 14px; margin-bottom: 16px; }
.price-list { list-style: none; padding: 0; margin: 0 0 22px; }
.price-list li { padding: 6px 0; font-size: 15px; color: var(--fg-soft); }
.price-list li::before { content: "✓"; color: var(--ok); font-weight: 700; margin-right: 8px; }

.feature-picker { display: grid; gap: 10px; }
.feature-pick {
    display: flex; gap: 12px; align-items: flex-start; padding: 13px 15px;
    border: 1px solid var(--line); border-radius: var(--radius-sm); cursor: pointer;
    background: #fff; transition: .15s ease;
}
.feature-pick:hover { border-color: var(--line-strong); background: #fcfdff; }
.feature-pick.checked { border-color: var(--brand); background: var(--brand-soft); }
.feature-pick.locked { opacity: .72; cursor: default; background: var(--bg-soft); }
.feature-pick input { margin-top: 4px; width: 17px; height: 17px; accent-color: var(--brand); flex: none; }
.feature-pick .fname { font-weight: 600; font-size: 15px; }
.feature-pick .fdesc { font-size: 13px; color: var(--muted); }
.feature-pick .fprice { margin-left: auto; font-family: var(--mono); font-size: 13.5px; color: var(--fg-soft); white-space: nowrap; }

.quote-box { position: sticky; top: 84px; }
.quote-line { display: flex; justify-content: space-between; padding: 8px 0; border-bottom: 1px dashed var(--line); font-size: 14.5px; }
.quote-line:last-of-type { border-bottom: 0; }
.quote-total { display: flex; justify-content: space-between; align-items: baseline; margin-top: 12px; padding-top: 14px; border-top: 2px solid var(--fg); }
.quote-total .num { font-size: 30px; font-weight: 800; }
.quote-cny { color: var(--muted); font-size: 13.5px; text-align: right; }

/* ───────────────────────── 表单 ───────────────────────── */

.field { margin-bottom: 16px; }
.field label { display: block; font-size: 13.5px; font-weight: 600; color: var(--fg-soft); margin-bottom: 6px; }
.field .hint { font-size: 12.5px; color: var(--muted); margin-top: 5px; }
.field.req label::after { content: " *"; color: var(--danger); }
input[type=text], input[type=email], input[type=tel], input[type=number], input[type=password], input[type=date],
select, textarea {
    width: 100%; padding: 11px 13px; border: 1px solid var(--line-strong); border-radius: var(--radius-sm);
    font: inherit; color: var(--fg); background: #fff; transition: .15s ease;
}
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px rgba(37, 99, 235, .15); }
textarea { min-height: 130px; resize: vertical; line-height: 1.65; }
.checkline { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; color: var(--fg-soft); }
.checkline input { margin-top: 4px; width: 17px; height: 17px; accent-color: var(--brand); flex: none; }
.form-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 0 16px; }

.alert { padding: 13px 16px; border-radius: var(--radius-sm); margin-bottom: 18px; font-size: 14.5px; }
.alert.err { background: var(--danger-soft); color: #991b1b; border: 1px solid #fecaca; }
.alert.ok { background: var(--ok-soft); color: #065f46; border: 1px solid #a7f3d0; }
.alert.warn { background: var(--warn-soft); color: #92400e; border: 1px solid #fde68a; }
.alert.info { background: var(--brand-soft); color: #1e40af; border: 1px solid #bfdbfe; }

/* ───────────────────────── 支付页 ───────────────────────── */

.pay-grid { display: grid; grid-template-columns: 1fr 340px; gap: 26px; align-items: start; }
.pay-box {
    background: var(--bg-dark); color: #e2e8f0; border-radius: var(--radius); padding: 24px;
    text-align: center;
}
.pay-box .qr { background: #fff; padding: 12px; border-radius: 12px; display: inline-block; }
.pay-box .qr img { display: block; width: 220px; height: 220px; }
.kv { display: flex; gap: 12px; align-items: center; justify-content: space-between; padding: 11px 0; border-bottom: 1px solid rgba(255, 255, 255, .1); text-align: left; }
.kv:last-child { border-bottom: 0; }
.kv .k { color: #94a3b8; font-size: 13px; flex: none; }
.kv .v { font-family: var(--mono); font-size: 13.5px; word-break: break-all; text-align: right; }
.copy-btn {
    border: 1px solid rgba(255, 255, 255, .25); background: rgba(255, 255, 255, .08); color: #e2e8f0;
    border-radius: 7px; padding: 4px 10px; font-size: 12px; cursor: pointer; flex: none;
}
.copy-btn:hover { background: rgba(255, 255, 255, .18); }
.amount-big { font-size: 40px; font-weight: 800; color: #fff; letter-spacing: -.02em; margin: 4px 0 2px; }
.amount-unit { color: #94a3b8; font-size: 14px; }

.status-bar { display: flex; align-items: center; gap: 12px; padding: 14px 18px; border-radius: var(--radius-sm); background: var(--bg-soft); border: 1px solid var(--line); }
.status-dot { width: 11px; height: 11px; border-radius: 50%; background: var(--warn); flex: none; animation: pulse 1.6s infinite; }
.status-dot.ok { background: var(--ok); animation: none; }
.status-dot.bad { background: var(--danger); animation: none; }
@keyframes pulse { 0%, 100% { opacity: 1; transform: scale(1); } 50% { opacity: .45; transform: scale(.82); } }

.cred-box { background: linear-gradient(135deg, #0b1220, #16233c); color: #e2e8f0; border-radius: var(--radius); padding: 26px; }
.cred-box .kv .v { color: #fff; }
.license-key {
    display: block; width: 100%; padding: 14px; margin-top: 8px; border-radius: 10px;
    background: rgba(255, 255, 255, .07); border: 1px dashed rgba(255, 255, 255, .28);
    font-family: var(--mono); font-size: 12.5px; line-height: 1.7; color: #fff;
    word-break: break-all; white-space: pre-wrap;
}
.steps { counter-reset: s; list-style: none; padding: 0; margin: 0; }
.steps li { position: relative; padding: 0 0 16px 40px; font-size: 15px; color: var(--fg-soft); }
.steps li::before {
    counter-increment: s; content: counter(s); position: absolute; left: 0; top: 1px;
    width: 26px; height: 26px; border-radius: 50%; background: var(--brand-soft); color: var(--brand);
    display: grid; place-items: center; font-size: 13px; font-weight: 700;
}
.steps li:last-child { padding-bottom: 0; }

/* ───────────────────────── 内容页 ───────────────────────── */

.prose { max-width: 780px; font-size: 16.5px; color: var(--fg-soft); }
.prose h2 { color: var(--fg); margin-top: 1.6em; }
.prose h3 { color: var(--fg); margin-top: 1.4em; }
.prose ul li, .prose ol li { margin-bottom: 6px; }
.prose img { border-radius: var(--radius-sm); border: 1px solid var(--line); }

.page-hero { padding: 52px 0 34px; background: var(--bg-soft); border-bottom: 1px solid var(--line); }
.page-hero h1 { margin-bottom: 8px; }
.page-hero p { color: var(--muted); font-size: 17px; max-width: 720px; margin: 0; }

.sop-step { display: grid; grid-template-columns: 54px 1fr; gap: 18px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.sop-step:last-child { border-bottom: 0; }
.sop-step .num {
    width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center;
    background: var(--brand-soft); color: var(--brand); font-size: 19px; font-weight: 800;
}
.sop-step h3 { margin-bottom: 4px; }
.sop-step .tab-tag { font-family: var(--mono); font-size: 12px; color: var(--brand); background: var(--brand-soft); padding: 2px 8px; border-radius: 6px; }

.gate { display: flex; gap: 14px; padding: 16px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: #fff; }
.gate .gi { font-size: 20px; flex: none; }
.gate strong { display: block; margin-bottom: 3px; }

.faq-item { border-bottom: 1px solid var(--line); }
.faq-item:last-child { border-bottom: 0; }
.faq-item summary { cursor: pointer; padding: 17px 0; font-weight: 600; font-size: 16.5px; list-style: none; display: flex; gap: 10px; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::before { content: "+"; color: var(--brand); font-weight: 800; }
.faq-item[open] summary::before { content: "−"; }
.faq-item .answer { padding: 0 0 18px 22px; color: var(--fg-soft); font-size: 15.5px; }

.post-card { display: flex; flex-direction: column; overflow: hidden; padding: 0; }
.post-card .thumb { aspect-ratio: 16 / 9; background: var(--bg-soft); object-fit: cover; width: 100%; }
.post-card .body { padding: 18px 20px 22px; display: flex; flex-direction: column; flex: 1; }
.post-card h3 { font-size: 17.5px; margin-bottom: 8px; }
.post-card .meta { font-size: 12.5px; color: var(--muted); margin-bottom: 10px; }
.post-card .excerpt { font-size: 14.5px; color: var(--fg-soft); flex: 1; }

.screen-card { padding: 0; overflow: hidden; }
.screen-card img { display: block; width: 100%; border-bottom: 1px solid var(--line); background: var(--bg-soft); }
.screen-card .body { padding: 14px 16px 18px; }
.screen-card h4 { font-size: 15.5px; margin-bottom: 4px; }
.screen-card p { font-size: 13px; color: var(--muted); margin: 0; }

.tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 22px; }
.tabs a { padding: 7px 15px; border-radius: 999px; border: 1px solid var(--line); font-size: 14px; color: var(--fg-soft); }
.tabs a.active { background: var(--brand); border-color: var(--brand); color: #fff; }

.pager { display: flex; gap: 8px; justify-content: center; margin-top: 32px; }
.pager a, .pager span { padding: 7px 14px; border: 1px solid var(--line); border-radius: 8px; font-size: 14px; }
.pager .cur { background: var(--brand); border-color: var(--brand); color: #fff; }

table.data { width: 100%; border-collapse: collapse; font-size: 14.5px; }
table.data th, table.data td { padding: 11px 12px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
table.data th { color: var(--muted); font-weight: 600; font-size: 13px; background: var(--bg-soft); }
table.data td.num { font-family: var(--mono); white-space: nowrap; }
table.data tr:last-child td { border-bottom: 0; }

/* ───────────────────────── 页脚 ───────────────────────── */

.site-footer { border-top: 1px solid var(--line); background: var(--bg-soft); padding: 46px 0 24px; margin-top: 20px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.4fr; gap: 28px; }
.footer-grid h4 { font-size: 14px; margin-bottom: 12px; }
.footer-grid a { display: block; font-size: 14px; color: var(--fg-soft); padding: 3px 0; }
.footer-grid a:hover { color: var(--brand); }
.footer-brand { font-weight: 700; font-size: 16px; margin-bottom: 8px; }
.footer-bottom { border-top: 1px solid var(--line); margin-top: 30px; padding-top: 18px; font-size: 13px; color: var(--muted); }

.cta-band { background: linear-gradient(135deg, #0b1220, #1e3a8a); color: #fff; border-radius: 20px; padding: 46px; text-align: center; }
.cta-band h2 { color: #fff; margin-bottom: 10px; }
.cta-band p { color: #cbd5e1; max-width: 620px; margin: 0 auto 24px; }

/* ───────────────────────── 响应式 ───────────────────────── */

@media (max-width: 980px) {
    .hero-grid { grid-template-columns: 1fr; gap: 30px; }
    .pay-grid { grid-template-columns: 1fr; }
    .quote-box { position: static; }
    .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
    .wrap { width: min(1160px, 100% - 28px); }
    section { padding: 46px 0; }
    .main-nav {
        display: none; position: absolute; top: 66px; left: 0; right: 0;
        flex-direction: column; background: #fff; border-bottom: 1px solid var(--line);
        padding: 10px 14px; box-shadow: var(--shadow);
    }
    .main-nav.open { display: flex; }
    .nav-toggle { display: block; }
    .header-actions .btn-ghost { display: none; }
    .cta-band { padding: 32px 22px; }
    .footer-grid { grid-template-columns: 1fr; }
    .sop-step { grid-template-columns: 42px 1fr; gap: 12px; }
    .grid-3, .grid-4 { grid-template-columns: 1fr; }
    h1 { font-size: 30px; }
}

@media print {
    .site-header, .site-footer, .btn { display: none !important; }
}