/* pi-book custom styles */

/* Better CJK typography */
:root {
    --content-max-width: 820px;
}

/* Body text: 18px for optimal reading experience (root 62.5% → 1rem=10px) */
.content main {
    font-size: 1.8rem;
    line-height: 1.85;
}

/* Mermaid diagram sizing */
.content main .mermaid {
    text-align: center;
    margin: 1.5em 0;
}

/* Blockquote positioning anchor styling */
.content main blockquote {
    border-left: 4px solid #4a9eff;
    background: #f0f7ff;
    padding: 0.8em 1.2em;
    margin: 1em 0;
}

/* Trade-off section emphasis */
.content main h3:has(+ p strong) {
    margin-top: 2em;
}

/* Code block with file reference */
.content main pre code {
    font-size: 0.88em;
    line-height: 1.5;
}

/* Version evolution note */
.content main blockquote:last-of-type {
    border-left-color: #9e9e9e;
    background: #f5f5f5;
    font-size: 0.92em;
}

/* === Sidebar TOC hierarchy === */

/* Part titles (篇): bold, distinct, no indent */
.chapter li.part-title {
    font-weight: 700;
    font-size: 1.5rem;
    margin-top: 1.2em;
    margin-bottom: 0.3em;
    color: var(--sidebar-fg);
    padding-left: 0;
    list-style: none;
}

/* Chapter items under parts: indent to show hierarchy */
.chapter li.chapter-item:not(.expanded):not(.affix) {
    padding-left: 1.5em;
}

/* Chapter links indentation */
.chapter li.chapter-item .chapter-link-wrapper {
    display: inline-block;
}