:root {
    --bg: #f8f9fb;
    --card: #ffffff;
    --text: #1a1a2e;
    --muted: #64748b;
    --accent: #2196F3;
    --accent-dark: #1565C0;
    --accent-light: #90CAF9;
    --border: #e2e8f0;
    --section-bg: #EBF5FB;
    --green: #10b981;
    --orange: #f59e0b;
    --red: #ef4444;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
}
.hero {
    background: linear-gradient(135deg, #0a1628 0%, #0d47a1 50%, #2196F3 100%);
    color: #fff;
    padding: 80px 24px 60px;
    text-align: center;
}
.hero h1 { font-size: 2.4rem; font-weight: 800; margin-bottom: 12px; letter-spacing: -0.5px; }
.hero .subtitle { font-size: 1.15rem; opacity: 0.85; max-width: 750px; margin: 0 auto 24px; }
.hero .meta { font-size: 0.85rem; opacity: 0.6; }
.hero .back-link {
    display: inline-block; margin-top: 16px; color: rgba(255,255,255,0.7);
    text-decoration: none; font-size: 0.9rem; border: 1px solid rgba(255,255,255,0.3);
    padding: 6px 16px; border-radius: 20px; transition: all 0.2s;
}
.hero .back-link:hover { background: rgba(255,255,255,0.1); color: #fff; }
.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }
.intro {
    background: var(--card); border: 1px solid var(--border); border-radius: 16px;
    padding: 40px; margin: -30px auto 40px; position: relative; z-index: 1; max-width: 960px;
}
.intro h2 { font-size: 1.3rem; margin-bottom: 12px; color: var(--accent); }
.intro p { color: var(--muted); font-size: 0.95rem; }
.toc { background: var(--section-bg); border-radius: 12px; padding: 28px 32px; margin-bottom: 48px; }
.toc h3 { font-size: 1rem; text-transform: uppercase; letter-spacing: 1px; color: var(--accent); margin-bottom: 14px; }
.toc ol { padding-left: 20px; }
.toc li { margin-bottom: 6px; font-size: 0.92rem; }
.toc a { color: var(--text); text-decoration: none; border-bottom: 1px dashed var(--accent-light); }
.toc a:hover { color: var(--accent); }
.section { margin-bottom: 56px; }
.section-header { display: flex; align-items: center; gap: 14px; margin-bottom: 20px; }
.section-number {
    background: var(--accent); color: #fff; width: 36px; height: 36px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: 0.9rem; flex-shrink: 0;
}
.section h2 { font-size: 1.4rem; font-weight: 700; }
.section h3 { margin: 20px 0 12px; font-size: 1.1rem; }
.section p, .section li { color: var(--muted); font-size: 0.95rem; margin-bottom: 12px; }
.section ul, .section ol { padding-left: 20px; margin-bottom: 16px; }
.screenshot {
    border: 1px solid var(--border); border-radius: 12px; overflow: hidden;
    margin: 20px 0; box-shadow: 0 4px 20px rgba(0,0,0,0.06);
}
.screenshot img { width: 100%; display: block; }
.screenshot .caption {
    background: #f7f7fa; padding: 10px 16px; font-size: 0.82rem;
    color: var(--muted); border-top: 1px solid var(--border);
}
.highlight-box {
    background: var(--section-bg); border-left: 4px solid var(--accent);
    border-radius: 0 10px 10px 0; padding: 18px 22px; margin: 16px 0; font-size: 0.92rem;
}
.highlight-box strong { color: var(--accent-dark); }
.tip-box {
    background: #fef9e7; border-left: 4px solid var(--orange);
    border-radius: 0 10px 10px 0; padding: 18px 22px; margin: 16px 0; font-size: 0.92rem;
}
.tip-box strong { color: #b7791f; }
.warning-box {
    background: #fef2f2; border-left: 4px solid var(--red);
    border-radius: 0 10px 10px 0; padding: 18px 22px; margin: 16px 0; font-size: 0.92rem;
}
.warning-box strong { color: var(--red); }
.metrics-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 14px; margin: 16px 0;
}
.metric-card {
    background: var(--card); border: 1px solid var(--border);
    border-radius: 10px; padding: 18px; text-align: center;
}
.metric-card .value { font-size: 1.6rem; font-weight: 800; color: var(--accent); }
.metric-card .label { font-size: 0.78rem; color: var(--muted); margin-top: 4px; }
.steps {
    background: var(--card); border: 1px solid var(--border);
    border-radius: 12px; padding: 24px 28px; margin: 20px 0;
}
.steps h4 { color: var(--accent-dark); margin-bottom: 12px; font-size: 1rem; }
.steps ol { padding-left: 20px; }
.steps li { margin-bottom: 8px; font-size: 0.92rem; color: var(--muted); }
.divider { border: none; height: 1px; background: var(--border); margin: 48px 0; }
footer {
    text-align: center; padding: 40px 24px; color: var(--muted);
    font-size: 0.82rem; border-top: 1px solid var(--border);
}
footer a { color: var(--accent); }
@media (max-width: 600px) {
    .hero h1 { font-size: 1.6rem; }
    .intro { padding: 24px; margin: -20px 16px 30px; }
    .metrics-grid { grid-template-columns: 1fr 1fr; }
}