/* ===== Reset & Base ===== */
* { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; }
body { font-family:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; background:#f8faff; color:#1a2639; line-height:1.6; padding-top:68px; }
a { color:#2563eb; text-decoration:none; }
a:hover { text-decoration:underline; }
img { max-width:100%; height:auto; display:block; }
.container { max-width:1200px; margin:0 auto; padding:0 24px; }

/* ===== Header ===== */
.site-header { position:fixed; top:0; left:0; right:0; z-index:1000; background:rgba(255,255,255,0.92); backdrop-filter:blur(12px); border-bottom:1px solid rgba(0,0,0,0.06); box-shadow:0 2px 16px rgba(0,0,0,0.04); height:68px; display:flex; align-items:center; }
.header-inner { display:flex; align-items:center; justify-content:space-between; width:100%; }
.logo { display:flex; align-items:center; gap:10px; font-weight:700; font-size:1.2rem; color:#1a2639; }
.logo img { width:32px; height:32px; border-radius:8px; }
.logo span { letter-spacing:-0.3px; }
.logo small { font-weight:400; font-size:0.75rem; color:#6b7280; margin-left:4px; }

.nav { display:flex; align-items:center; gap:28px; }
.nav a { color:#374151; font-size:0.95rem; font-weight:500; transition:color 0.2s; position:relative; }
.nav a:hover { color:#2563eb; text-decoration:none; }
.nav a.active { color:#2563eb; }
.nav a.active::after { content:''; position:absolute; bottom:-4px; left:0; right:0; height:2px; background:#2563eb; border-radius:4px; }

.btn { display:inline-flex; align-items:center; justify-content:center; padding:10px 24px; border-radius:10px; font-weight:600; font-size:0.95rem; border:none; cursor:pointer; transition:all 0.25s ease; gap:6px; }
.btn-primary { background:linear-gradient(135deg,#2563eb,#1d4ed8); color:#fff; box-shadow:0 4px 14px rgba(37,99,235,0.3); }
.btn-primary:hover { background:linear-gradient(135deg,#1d4ed8,#1e40af); color:#fff; box-shadow:0 8px 28px rgba(37,99,235,0.35); transform:translateY(-1px); }
.btn-secondary { background:#eef2ff; color:#2563eb; border:1px solid #dbeafe; }
.btn-secondary:hover { background:#dbeafe; color:#1d4ed8; box-shadow:0 4px 12px rgba(37,99,235,0.12); }
.btn-lg { padding:14px 36px; font-size:1.05rem; border-radius:12px; }

.header-cta { display:flex; }
.nav-toggle { display:none; flex-direction:column; gap:5px; background:none; border:none; cursor:pointer; padding:6px; }
.nav-toggle span { display:block; width:26px; height:2.5px; background:#1a2639; border-radius:4px; transition:all 0.25s; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform:rotate(45deg) translate(5px,5px); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity:0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform:rotate(-45deg) translate(5px,-5px); }

/* ===== Hero (首页) ===== */
.hero { padding:60px 0 40px; background:linear-gradient(180deg,#f0f5ff 0%,#f8faff 100%); }
.hero-grid { display:grid; grid-template-columns:1fr 1fr; gap:48px; align-items:center; }
.eyebrow { display:inline-block; background:#dbeafe; color:#1d4ed8; font-size:0.8rem; font-weight:600; padding:4px 14px; border-radius:20px; margin-bottom:16px; }
.hero h1 { font-size:2.8rem; font-weight:800; line-height:1.15; color:#0f172a; margin-bottom:16px; }
.hero-lead { font-size:1.15rem; color:#374151; max-width:520px; margin-bottom:28px; line-height:1.7; }
.hero-actions { display:flex; flex-wrap:wrap; gap:16px; margin-bottom:28px; }
.trust-list { display:flex; flex-wrap:wrap; gap:20px 36px; list-style:none; font-size:0.9rem; color:#4b5563; }
.trust-list li { display:flex; align-items:center; gap:8px; }
.trust-list li::before { content:'✓'; display:inline-flex; align-items:center; justify-content:center; width:20px; height:20px; background:#dbeafe; color:#2563eb; border-radius:50%; font-weight:700; font-size:0.7rem; flex-shrink:0; }
.hero-visual img { border-radius:20px; box-shadow:0 20px 60px rgba(0,0,0,0.08); }

/* ===== 通用 Sections ===== */
.section { padding:64px 0; }
.section-alt { background:#ffffff; }
.section-head { text-align:center; max-width:640px; margin:0 auto 48px; }
.section-head h2 { font-size:2rem; font-weight:700; color:#0f172a; margin-bottom:10px; }
.section-head p { color:#4b5563; font-size:1.05rem; }

.grid-3 { display:grid; grid-template-columns:repeat(3,1fr); gap:32px; }
.card { background:#fff; border-radius:20px; padding:32px 28px; box-shadow:0 4px 20px rgba(0,0,0,0.04); border:1px solid rgba(0,0,0,0.04); transition:transform 0.2s, box-shadow 0.2s; }
.card:hover { transform:translateY(-4px); box-shadow:0 12px 40px rgba(0,0,0,0.06); }
.card-icon { font-size:2.4rem; font-weight:700; color:#2563eb; margin-bottom:12px; }
.card h3 { font-size:1.2rem; font-weight:700; margin-bottom:8px; }
.card p { color:#4b5563; font-size:0.95rem; }

.steps { display:flex; flex-direction:column; gap:20px; max-width:820px; margin:0 auto; }
.step { display:flex; gap:20px; align-items:flex-start; background:#fff; padding:20px 28px; border-radius:16px; box-shadow:0 2px 12px rgba(0,0,0,0.04); border:1px solid rgba(0,0,0,0.04); }
.step-num { flex-shrink:0; width:44px; height:44px; background:#2563eb; color:#fff; font-weight:700; font-size:1.1rem; border-radius:50%; display:flex; align-items:center; justify-content:center; margin-top:2px; }
.step h3 { font-size:1.05rem; font-weight:700; margin-bottom:4px; }
.step p { color:#4b5563; font-size:0.95rem; }
.step .kbd { display:inline-block; background:#f1f5f9; padding:0 8px; border-radius:4px; font-weight:600; font-size:0.85rem; border:1px solid #e2e8f0; }

.notice { max-width:820px; margin:24px auto 0; padding:16px 24px; background:#fffbeb; border-left:4px solid #f59e0b; border-radius:8px; color:#78350f; font-size:0.9rem; }

.table-wrap { overflow-x:auto; border-radius:16px; border:1px solid #e5e7eb; background:#fff; box-shadow:0 2px 12px rgba(0,0,0,0.03); }
table { width:100%; border-collapse:collapse; font-size:0.95rem; min-width:480px; }
thead { background:#f8fafc; }
th { padding:14px 20px; text-align:left; font-weight:600; color:#0f172a; border-bottom:2px solid #e5e7eb; }
td { padding:14px 20px; border-bottom:1px solid #f1f5f9; color:#1e293b; }
tr:last-child td { border-bottom:none; }
tbody tr:hover { background:#f8fafc; }

.cover-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:24px; }
.cover-grid figure { background:#fff; border-radius:16px; overflow:hidden; box-shadow:0 2px 12px rgba(0,0,0,0.04); border:1px solid rgba(0,0,0,0.04); transition:transform 0.2s; }
.cover-grid figure:hover { transform:translateY(-4px); }
.cover-grid img { width:100%; aspect-ratio:1/1; object-fit:cover; background:#f1f5f9; }
.cover-grid figcaption { padding:12px 16px; font-weight:500; font-size:0.9rem; text-align:center; color:#1e293b; background:#fff; }

.faq { max-width:780px; margin:0 auto; display:flex; flex-direction:column; gap:8px; }
.faq details { background:#fff; border-radius:12px; border:1px solid #e5e7eb; padding:4px 0; }
.faq details[open] { border-color:#2563eb; box-shadow:0 2px 12px rgba(37,99,235,0.06); }
.faq summary { padding:16px 24px; font-weight:600; cursor:pointer; display:flex; align-items:center; justify-content:space-between; user-select:none; list-style:none; }
.faq summary::-webkit-details-marker { display:none; }
.faq summary::after { content:'▾'; font-size:1.1rem; color:#6b7280; transition:transform 0.25s; }
.faq details[open] summary::after { transform:rotate(180deg); }
.faq details p { padding:0 24px 20px; color:#4b5563; font-size:0.95rem; margin:0; }

.cta-band { display:flex; align-items:center; justify-content:space-between; background:linear-gradient(135deg,#1e293b,#0f172a); border-radius:24px; padding:48px 56px; color:#fff; gap:32px; flex-wrap:wrap; }
.cta-band h2 { font-size:1.8rem; font-weight:700; margin-bottom:6px; }
.cta-band p { color:#cbd5e1; font-size:1.05rem; }
.cta-band .btn-primary { background:linear-gradient(135deg,#3b82f6,#2563eb); flex-shrink:0; }
.cta-band .btn-primary:hover { background:linear-gradient(135deg,#2563eb,#1d4ed8); }

/* ===== Footer ===== */
.site-footer { background:#0f172a; color:#94a3b8; padding:48px 0 24px; border-top:1px solid #1e293b; }
.footer-grid { display:grid; grid-template-columns:2fr 1fr 1fr; gap:48px; margin-bottom:32px; }
.footer-brand { font-size:1.3rem; font-weight:700; color:#fff; margin-bottom:12px; }
.footer-note { font-size:0.9rem; line-height:1.7; max-width:360px; }
.footer-note a { color:#60a5fa; }
.footer-note a:hover { color:#93bbfc; }
.footer-grid h3 { color:#fff; font-size:1rem; font-weight:600; margin-bottom:14px; }
.footer-grid ul { list-style:none; display:flex; flex-direction:column; gap:8px; }
.footer-grid ul a { color:#94a3b8; font-size:0.9rem; transition:color 0.2s; }
.footer-grid ul a:hover { color:#fff; text-decoration:none; }

.friend-links { border-top:1px solid #1e293b; padding-top:20px; margin-top:8px; display:flex; flex-wrap:wrap; align-items:center; gap:8px 20px; font-size:0.85rem; }
.friend-links-label { color:#64748b; font-weight:500; }
.friend-links a { color:#94a3b8; transition:color 0.2s; }
.friend-links a:hover { color:#fff; text-decoration:none; }

.footer-bottom { border-top:1px solid #1e293b; padding-top:20px; margin-top:20px; display:flex; justify-content:space-between; align-items:center; flex-wrap:wrap; gap:12px; font-size:0.85rem; }
.footer-bottom a { color:#94a3b8; }
.footer-bottom a:hover { color:#fff; text-decoration:none; }
.download-stats { color:#94a3b8; font-size:0.85rem; }
.download-stats span { margin:0 4px; font-weight:600; color:#e2e8f0; }

.footer-sponsor { text-align:center; margin-top:20px; padding-top:16px; border-top:1px solid #1e293b; }
.footer-sponsor-link { display:inline-block; opacity:0.6; transition:opacity 0.2s; }
.footer-sponsor-link:hover { opacity:1; }
.footer-sponsor-link img { border-radius:8px; }

/* ===== 非官方声明 ===== */
.official-disclaimer { background:#fef2f2; border:1px solid #fca5a5; border-radius:8px; padding:12px 20px; margin:16px 0; color:#991b1b; font-weight:bold; text-align:center; font-size:0.95rem; }

/* ===== Float Download ===== */
.float-download { position:fixed; bottom:28px; left:50%; transform:translateX(-50%); z-index:999; background:rgba(255,255,255,0.96); backdrop-filter:blur(12px); box-shadow:0 8px 40px rgba(0,0,0,0.12); border-radius:16px; padding:14px 24px; border:1px solid rgba(0,0,0,0.04); display:flex; align-items:center; gap:24px; transition:all 0.3s ease; max-width:90%; opacity:0; transform:translateX(-50%) translateY(20px); pointer-events:none; }
.float-download.show { opacity:1; transform:translateX(-50%) translateY(0); pointer-events:auto; }
.float-download strong { color:#0f172a; font-size:0.95rem; }
.float-download span { font-size:0.8rem; color:#6b7280; display:block; font-weight:400; }
.float-download .btn { flex-shrink:0; padding:8px 20px; font-size:0.85rem; }

/* ===== 教程页专用 ===== */
.breadcrumb-wrap { padding-top:20px; }
.breadcrumb { font-size:0.9rem; color:#6b7280; padding:8px 0; }
.breadcrumb a { color:#2563eb; }
.breadcrumb a:hover { text-decoration:underline; }

.page-hero { padding:20px 0 8px; }
.page-hero h1 { font-size:2.2rem; font-weight:800; color:#0f172a; margin-bottom:8px; }
.page-hero p { font-size:1.1rem; color:#4b5563; max-width:720px; }

.guide-steps { display:flex; flex-direction:column; gap:48px; max-width:1000px; margin:0 auto; }
.guide-step { display:grid; grid-template-columns:1fr 1fr; gap:40px; align-items:center; background:#fff; border-radius:20px; padding:32px; box-shadow:0 4px 24px rgba(0,0,0,0.04); border:1px solid rgba(0,0,0,0.04); }
.guide-step-copy { display:flex; gap:16px; align-items:flex-start; }
.guide-step-copy .step-num { flex-shrink:0; width:44px; height:44px; background:#2563eb; color:#fff; font-weight:700; font-size:1.2rem; border-radius:50%; display:flex; align-items:center; justify-content:center; }
.guide-step-copy h3 { font-size:1.2rem; font-weight:700; margin-bottom:6px; }
.guide-step-copy p { color:#4b5563; margin-bottom:8px; }
.tip-list { list-style:none; padding:0; display:flex; flex-wrap:wrap; gap:8px 16px; }
.tip-list li { font-size:0.9rem; color:#374151; display:flex; align-items:center; }
.tip-list li::before { content:'•'; color:#2563eb; font-weight:bold; margin-right:6px; }
.guide-shot { margin:0; }
.guide-shot img { width:100%; border-radius:12px; box-shadow:0 8px 24px rgba(0,0,0,0.08); background:#f1f5f9; }
.guide-shot figcaption { text-align:center; font-size:0.85rem; color:#6b7280; margin-top:8px; }

/* ===== Responsive ===== */
@media (max-width:992px) {
    .hero-grid { grid-template-columns:1fr; text-align:center; }
    .hero-lead { margin-left:auto; margin-right:auto; }
    .hero-actions { justify-content:center; }
    .trust-list { justify-content:center; }
    .hero-visual { order:-1; }
    .hero h1 { font-size:2.2rem; }
    .grid-3 { grid-template-columns:repeat(2,1fr); }
    .cover-grid { grid-template-columns:repeat(2,1fr); }
    .footer-grid { grid-template-columns:1fr 1fr; gap:32px; }
    .cta-band { flex-direction:column; text-align:center; padding:36px 28px; }
    .guide-step { grid-template-columns:1fr; gap:24px; }
}
@media (max-width:768px) {
    body { padding-top:60px; }
    .site-header { height:60px; }
    .header-cta { display:none; }
    .nav-toggle { display:flex; }
    .nav { display:none; position:absolute; top:60px; left:0; right:0; background:rgba(255,255,255,0.98); backdrop-filter:blur(12px); flex-direction:column; padding:20px 24px; gap:16px; border-bottom:1px solid rgba(0,0,0,0.06); box-shadow:0 12px 32px rgba(0,0,0,0.06); }
    .nav.open { display:flex; }
    .nav a { font-size:1rem; padding:6px 0; }
    .nav a.active::after { display:none; }
    .hero { padding:40px 0 24px; }
    .hero h1 { font-size:1.8rem; }
    .hero-lead { font-size:1rem; }
    .grid-3 { grid-template-columns:1fr; }
    .section { padding:40px 0; }
    .section-head h2 { font-size:1.6rem; }
    .step { flex-direction:column; padding:16px 20px; }
    .step-num { width:36px; height:36px; font-size:0.95rem; }
    .cover-grid { grid-template-columns:1fr 1fr; gap:16px; }
    .footer-grid { grid-template-columns:1fr; gap:24px; }
    .float-download { bottom:16px; padding:12px 16px; gap:12px; flex-wrap:wrap; justify-content:center; border-radius:12px; }
    .float-download strong { font-size:0.85rem; }
    .float-download span { font-size:0.7rem; }
    .float-download .btn { padding:6px 16px; font-size:0.8rem; }
    .cta-band { padding:28px 20px; }
    .cta-band h2 { font-size:1.4rem; }
    .friend-links { gap:4px 12px; font-size:0.8rem; }
    .footer-bottom { flex-direction:column; text-align:center; }
    .table-wrap { border-radius:12px; }
    table { font-size:0.85rem; min-width:360px; }
    th,td { padding:10px 14px; }
    .guide-step { padding:20px; }
    .guide-step-copy { flex-direction:column; }
    .page-hero h1 { font-size:1.8rem; }
}
@media (max-width:480px) {
    .container { padding:0 16px; }
    .hero h1 { font-size:1.5rem; }
    .hero-actions .btn { width:100%; justify-content:center; }
    .cover-grid { grid-template-columns:1fr 1fr; gap:12px; }
    .cover-grid figcaption { font-size:0.75rem; padding:8px 10px; }
    .float-download { padding:10px 12px; gap:8px; bottom:12px; border-radius:10px; width:calc(100% - 32px); max-width:100%; }
    .float-download .btn { padding:5px 12px; font-size:0.75rem; }
    .float-download strong { font-size:0.8rem; }
    .float-download span { font-size:0.65rem; }
    .guide-step { padding:16px; }
    .guide-step-copy .step-num { width:36px; height:36px; font-size:1rem; }
}