body { background: #f0f4ff; }

.navbar {
    border-bottom: 1px solid rgba(0,0,0,0.35);
    box-shadow: 0 4px 6px rgba(0,0,0,0.18);
}

.navbar::after {
    content: '';
    position: absolute;
    bottom: -18px;
    left: 0;
    right: 0;
    height: 18px;
    background: linear-gradient(to bottom, rgba(0,0,0,0.10), transparent);
    pointer-events: none;
    z-index: 999;
}

.page-wrapper {
    max-width: 860px;
    margin: 2.5rem auto;
    padding: 0 1.25rem 4rem;
    font-family: Inter, sans-serif;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    color: #fff;
    background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 700;
    padding: 0.5rem 1.2rem;
    border-radius: 8px;
    box-shadow: 0 4px 14px rgba(37, 99, 235, 0.45);
    transition: transform 0.2s, box-shadow 0.2s;
    letter-spacing: 0.02em;
}
.back-link .back-arrow { display: inline-block; transition: transform 0.2s; }
.back-link:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(37, 99, 235, 0.6); }
.back-link:hover .back-arrow { transform: translateX(-4px); }
.back-link:active { transform: translateY(0); box-shadow: 0 4px 14px rgba(37, 99, 235, 0.45); }

h1 {
    font-size: 2rem;
    color: #1e1e2e;
    margin-bottom: 0.3rem;
}

.subtitle {
    color: #555;
    margin-bottom: 2.5rem;
    font-size: 1rem;
}

.toc {
    background: white;
    border: 1px solid #dde3f0;
    border-left: 4px solid #2563eb;
    border-radius: 10px;
    padding: 1.25rem 1.5rem;
    margin-bottom: 2.5rem;
}
.toc h2 { font-size: 1rem; color: #444; margin-bottom: 0.75rem; text-transform: uppercase; letter-spacing: 0.05em; }
.toc ol { margin: 0; padding-left: 1.4rem; }
.toc li { margin-bottom: 0.3rem; }
.toc a { color: #2563eb; text-decoration: none; font-size: 0.95rem; }
.toc a:hover { text-decoration: underline; }

.section {
    background: white;
    border-radius: 12px;
    border: 1px solid #dde3f0;
    padding: 1.75rem 2rem;
    margin-bottom: 1.75rem;
}

.section h2 {
    font-size: 1.3rem;
    color: #1e1e2e;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #e0e7ff;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.section h3 {
    font-size: 1rem;
    color: #374151;
    margin: 1.25rem 0 0.5rem;
}

.section p, .section li {
    font-size: 0.95rem;
    color: #444;
    line-height: 1.65;
}

.section ul, .section ol {
    padding-left: 1.4rem;
    margin-bottom: 0.75rem;
}

pre {
    background: #1e1e2e;
    color: #cdd6f4;
    border-radius: 8px;
    padding: 1.1rem 1.25rem;
    overflow-x: auto;
    font-size: 0.88rem;
    line-height: 1.6;
    margin: 0.75rem 0;
    font-family: 'Courier New', Courier, monospace;
}

code {
    background: #e8ecf8;
    color: #2563eb;
    padding: 0.15em 0.4em;
    border-radius: 4px;
    font-size: 0.88em;
    font-family: 'Courier New', Courier, monospace;
}

pre code {
    background: none;
    color: inherit;
    padding: 0;
    font-size: inherit;
}

.kw  { color: #cba6f7; }
.fn  { color: #89b4fa; }
.st  { color: #a6e3a1; }
.cm  { color: #6c7086; font-style: italic; }
.nm  { color: #fab387; }
.vr  { color: #f38ba8; }
.op  { color: #89dceb; }

.note {
    background: #eff6ff;
    border-left: 4px solid #2563eb;
    border-radius: 0 8px 8px 0;
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    color: #1e40af;
    margin: 0.75rem 0;
}

.tip {
    background: #f0fdf4;
    border-left: 4px solid #16a34a;
    border-radius: 0 8px 8px 0;
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    color: #166534;
    margin: 0.75rem 0;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.92rem;
    margin-top: 0.75rem;
}
th {
    background: #f1f5fb;
    padding: 0.6rem 0.85rem;
    text-align: left;
    color: #374151;
    border-bottom: 2px solid #dde3f0;
}
td {
    padding: 0.55rem 0.85rem;
    border-bottom: 1px solid #eef0f6;
    color: #444;
}
tr:last-child td { border-bottom: none; }