:root {
    --bg: #0b0d13;
    --card-bg: rgba(22, 27, 38, 0.7);
    --card-border: rgba(255, 255, 255, 0.08);
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent: #38bdf8;
    --accent-glow: rgba(56, 189, 248, 0.15);
    --badge-bg: rgba(56, 189, 248, 0.12);
    --warning-border: rgba(245, 158, 11, 0.3);
    --warning-bg: rgba(245, 158, 11, 0.08);
    --warning-text: #fde68a;
    --maxw: 840px;
    --font-sans: "Plus Jakarta Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg);
    color: var(--text-primary);
    line-height: 1.7;
    background-image:
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(56, 189, 248, 0.12), transparent 70%),
        radial-gradient(ellipse 60% 40% at 90% 80%, rgba(99, 102, 241, 0.08), transparent 60%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
}

header {
    position: sticky;
    top: 0;
    z-index: 50;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    background: rgba(11, 13, 19, 0.75);
    border-bottom: 1px solid var(--card-border);
}

.nav-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 1rem clamp(1.25rem, 5vw, 2rem);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--text-primary);
    text-decoration: none;
}

.brand-badge {
    font-size: 0.75rem;
    background: var(--badge-bg);
    color: var(--accent);
    border: 1px solid rgba(56, 189, 248, 0.3);
    padding: 0.15rem 0.55rem;
    border-radius: 9999px;
    font-weight: 600;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.25rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.925rem;
    font-weight: 500;
    transition: color 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.nav-link:hover {
    color: var(--text-primary);
}

.back-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    color: var(--text-primary);
    padding: 0.45rem 0.9rem;
    border-radius: 8px;
    font-size: 0.875rem;
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    text-decoration: none;
}

main {
    max-width: var(--maxw);
    margin: 2rem auto 4rem;
    padding: 0 clamp(1.25rem, 5vw, 2rem);
    width: 100%;
    flex: 1;
}

.doc-header {
    margin-bottom: 2.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--card-border);
}

.doc-tag {
    display: inline-block;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.75rem;
    color: var(--accent);
    font-weight: 700;
    margin-bottom: 0.5rem;
}

h1 {
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.2;
    margin-bottom: 0.75rem;
}

.meta-info {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.nav-tabs {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.tab-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
}

.tab-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    text-decoration: none;
}

.doc-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: clamp(1.25rem, 4vw, 2.5rem);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
    margin-bottom: 2rem;
}

.doc-card section {
    margin-bottom: 2.25rem;
}

.doc-card section:last-child {
    margin-bottom: 0;
}

h2 {
    color: var(--text-primary);
    font-size: 1.35rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 0.85rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-size: 0.975rem;
}

ul {
    list-style: none;
    margin-bottom: 1rem;
    display: grid;
    gap: 0.75rem;
}

li {
    color: var(--text-secondary);
    font-size: 0.975rem;
    padding-left: 1.5rem;
    position: relative;
}

li::before {
    content: "•";
    color: var(--accent);
    font-weight: bold;
    font-size: 1.2rem;
    position: absolute;
    left: 0.4rem;
    top: -0.1rem;
}

strong {
    color: var(--text-primary);
    font-weight: 600;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: opacity 0.2s;
}

a:hover {
    text-decoration: underline;
}

.callout {
    background: rgba(56, 189, 248, 0.06);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: 12px;
    padding: 1.25rem 1.5rem;
    margin: 1.5rem 0;
}

.callout p {
    margin-bottom: 0;
    color: #bae6fd;
}

.alert-box {
    background: var(--warning-bg);
    border: 1px solid var(--warning-border);
    border-radius: 12px;
    padding: 1.25rem 1.5rem;
    margin: 1.5rem 0;
}

.alert-box h3 {
    color: var(--warning-text);
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.alert-box p {
    margin-bottom: 0;
    color: #fef3c7;
    font-size: 0.925rem;
}

footer {
    border-top: 1px solid var(--card-border);
    padding: 2rem 1.5rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
}

@media (max-width: 640px) {
    .doc-card {
        padding: 1.5rem;
    }
    .meta-info {
        gap: 0.75rem;
    }
}