/* docs 站点基础样式：极简讲义风 */

:root {
    --ink: #1a1a2e;
    --ink-light: #4a4a6a;
    --ink-muted: #6b6b8a;
    --paper: #fafaf9;
    --paper-elevated: #ffffff;
    --accent: #0d9488;
    --accent-hover: #0f766e;
    --theory: #0369a1;
    --lab: #a21caf;
    --border: #e7e5e4;
    --radius: 0px;
    --font-sans: system-ui, -apple-system, "Segoe UI", Arial, sans-serif;
    --font-serif: var(--font-sans);
    --shadow-sm: none;
    --shadow-md: none;
    --tint: transparent;
}

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

body {
    font-family: var(--font-sans);
    background: var(--paper);
    color: var(--ink);
    line-height: 1.7;
    font-weight: 400;
}

/* 极简风：不使用背景色带、阴影、气泡 */

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    color: var(--accent-hover);
    text-decoration: none;
}

/* ---- 极简布局（index/文章页可复用） ---- */
.book-shell {
    height: 100vh;
    display: grid;
    grid-template-columns: 300px 1fr;
}

.book-sidebar {
    border-right: 1px solid var(--border);
    background: #f7f7f7;
    overflow: auto;
    padding: 12px 0;
}

.book-main {
    overflow: auto;
    padding: 26px 28px;
}

.book-brand {
    padding: 10px 18px 12px;
    font-size: 13px;
    font-weight: 700;
    color: var(--ink);
    border-bottom: 1px solid var(--border);
    margin-bottom: 10px;
}

.book-nav {
    list-style: none;
    margin: 0;
    padding: 0;
}

.book-nav a {
    display: block;
    padding: 8px 18px;
    color: var(--ink-light);
    text-decoration: none !important;
    font-size: 13px;
}

.book-nav a:hover {
    color: var(--ink);
}

.book-nav a.is-active {
    color: var(--accent-hover);
    font-weight: 700;
    border-left: 3px solid var(--accent);
    padding-left: 15px;
    background: transparent;
}

.book-main h1 {
    font-size: 28px;
    font-weight: 700;
    margin: 0 0 14px;
    letter-spacing: -0.01em;
}

.book-main h2 {
    font-size: 18px;
    font-weight: 700;
    margin: 26px 0 12px;
}

.book-main h3 {
    font-size: 15px;
    font-weight: 700;
    margin: 18px 0 8px;
}

.book-main p,
.book-main li {
    color: var(--ink-light);
}

.book-main code {
    background: #f2f2f2;
    border: 1px solid #e5e5e5;
    padding: 0 6px;
    border-radius: 6px;
    color: var(--ink);
}

.book-main pre {
    border: 1px solid #e5e5e5;
    background: #fff;
    padding: 12px;
    overflow: auto;
    margin: 12px 0 16px;
    position: relative;
}

.book-main pre code {
    background: transparent;
    border: 0;
    padding: 0;
}

.book-callout {
    border-left: 3px solid var(--accent);
    padding: 10px 12px;
    margin: 12px 0 16px;
    background: transparent;
    color: var(--ink);
}

.book-footer {
    margin-top: 22px;
    font-size: 12px;
    color: var(--ink-muted);
}

@media (max-width: 980px) {
    .book-shell {
        grid-template-columns: 1fr;
        height: auto;
    }

    .book-sidebar {
        position: relative;
        max-height: 40vh;
        border-right: 0;
        border-bottom: 1px solid var(--border);
    }

    .book-main {
        overflow: visible;
        padding: 18px 16px;
    }
}

/* ----- Header ----- */
.site-header {
    padding: 4rem 0 3rem;
    text-align: center;
    border-bottom: 1px solid var(--border);
}

.kicker {
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--ink-muted);
    margin-bottom: 0.5rem;
}

.title {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 400;
    color: var(--ink);
    line-height: 1.25;
    margin-bottom: 1rem;
}

.lead {
    font-size: 1.05rem;
    color: var(--ink-light);
    max-width: 640px;
    margin: 0 auto 1.5rem;
}

.cta {
    display: inline-block;
    padding: 0.65rem 1.5rem;
    background: var(--ink);
    color: var(--paper) !important;
    font-weight: 500;
    border-radius: var(--radius);
    text-decoration: none !important;
}

.cta:hover {
    background: var(--ink-light);
    text-decoration: none !important;
}

.cta--secondary {
    background: var(--accent);
}

.cta--secondary:hover {
    background: var(--accent-hover);
}

/* ----- Blocks ----- */
.block {
    padding: 2.5rem 0;
}

.block-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 1.25rem;
    letter-spacing: -0.01em;
}

/* Intro */
.intro-text {
    color: var(--ink-light);
    font-size: 1rem;
}

/* Modules */
.block--modules {
    background: var(--paper-elevated);
    border-top: 1px solid var(--border);
}

.modules {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.module {
    padding: 1.25rem 1.5rem;
    background: var(--paper);
    border: 1px solid var(--border);
    border-radius: var(--radius);
}

.module-num {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.module h3 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 0.5rem;
}

.module p {
    font-size: 0.95rem;
    color: var(--ink-light);
}

/* Calendar */
.calendar {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.cal-row {
    display: grid;
    grid-template-columns: 6em 10em 1fr;
    gap: 1rem;
    align-items: baseline;
    padding: 0.6rem 0;
    border-bottom: 1px solid var(--border);
    font-size: 0.95rem;
}

.cal-row:last-child {
    border-bottom: none;
}

.cal-period {
    font-weight: 500;
    color: var(--ink);
}

.cal-date {
    color: var(--ink-muted);
    font-size: 0.9rem;
}

.cal-desc {
    color: var(--ink-light);
}

.cal-desc strong {
    color: var(--ink);
}

.cal-row--theory .cal-period {
    color: var(--theory);
}

.cal-row--lab .cal-period {
    color: var(--lab);
}

/* Outcomes */
.outcome-list {
    list-style: none;
}

.outcome-list li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--ink-light);
}

.outcome-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.6em;
    width: 6px;
    height: 6px;
    background: var(--accent);
    border-radius: 50%;
}

/* Materials */
.block--materials {
    background: var(--paper-elevated);
    border-top: 1px solid var(--border);
}

.materials-intro {
    color: var(--ink-light);
    margin-bottom: 1.25rem;
    font-size: 0.95rem;
}

.materials-grid {
    display: grid;
    gap: 1rem;
}

.material-item {
    padding: 1rem 1.25rem;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--paper);
}

.material-item h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 0.35rem;
}

.material-item p {
    font-size: 0.9rem;
    color: var(--ink-light);
}

/* Instructor */
.instructor-card {
    display: flex;
    gap: 1.5rem;
    align-items: flex-start;
    padding: 1.5rem;
    background: var(--paper-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius);
}

.instructor-avatar {
    width: 72px;
    height: 72px;
    min-width: 72px;
    border-radius: 50%;
    background: linear-gradient(145deg, #e2e8f0, #cbd5e1);
    color: var(--ink-light);
    font-size: 1.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
}

.instructor-info h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 0.5rem;
}

.instructor-info p {
    font-size: 0.95rem;
    color: var(--ink-light);
    margin-bottom: 0.5rem;
}

.instructor-info p:last-child {
    margin-bottom: 0;
}

.instructor-philosophy {
    font-size: 0.9rem;
    color: var(--ink-muted);
    font-style: italic;
}

/* Start */
.block--start {
    text-align: center;
    padding: 3rem 0;
    border-top: 1px solid var(--border);
}

.start-text {
    color: var(--ink-light);
    margin-bottom: 1.25rem;
    max-width: 560px;
    margin-left: auto;
    margin-right: auto;
}

/* Footer */
.site-footer {
    padding: 2rem 0;
    text-align: center;
    font-size: 0.85rem;
    color: var(--ink-muted);
    border-top: 1px solid var(--border);
}

/* ----- Responsive ----- */
@media (max-width: 640px) {
    .site-header {
        padding: 3rem 0 2rem;
    }

    .cal-row {
        grid-template-columns: 1fr;
        gap: 0.25rem;
    }

    .cal-date {
        font-size: 0.85rem;
    }

    .instructor-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
}

/* -------------------- 目录页（参考图：顶栏 + 侧栏 + 卡片区） -------------------- */
.app-header {
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(250, 250, 249, 0.88);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
}

.app-header__inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 14px 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.app-header__title {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
}

.app-badge {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    background: radial-gradient(circle at 30% 30%, rgba(13,148,136,0.22), rgba(13,148,136,0.10) 55%, rgba(13,148,136,0.04));
    border: 1px solid rgba(13,148,136,0.18);
    box-shadow: var(--shadow-sm);
}

.app-header__kicker {
    font-size: 12px;
    color: var(--ink-muted);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    line-height: 1.2;
}

.app-header__name {
    font-size: 16px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.2;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 70vw;
}

.app-header__actions {
    display: flex;
    gap: 10px;
    align-items: center;
}

.app-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 10px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: rgba(255,255,255,0.65);
    box-shadow: var(--shadow-sm);
    color: var(--ink);
    text-decoration: none !important;
}

.app-link:hover {
    background: rgba(255,255,255,0.95);
    text-decoration: none !important;
}

.app-shell {
    max-width: 1200px;
    margin: 0 auto;
    padding: 18px;
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 18px;
    align-items: start;
}

.app-panel {
    background: rgba(255,255,255,0.86);
    border: 1px solid var(--border);
    border-radius: 14px;
    box-shadow: var(--shadow-md);
}

.app-sidebar__panel {
    padding: 14px;
}

.app-panel__header {
    padding: 16px 18px 10px;
    border-bottom: 1px solid var(--border);
}

.app-panel__title {
    font-weight: 700;
    color: var(--ink);
    font-size: 16px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.app-panel__sub {
    margin-top: 4px;
    color: var(--ink-muted);
    font-size: 12.5px;
}

.app-sidebar__links {
    margin-top: 10px;
    display: grid;
    gap: 8px;
}

.app-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    border-radius: 12px;
    border: 1px solid rgba(231,229,228,0.8);
    background: rgba(250,250,249,0.7);
    color: var(--ink);
    text-decoration: none !important;
}

.app-nav:hover {
    background: rgba(255,255,255,0.95);
    border-color: rgba(13,148,136,0.25);
}

.app-main > .app-panel {
    padding-bottom: 16px;
}

.app-grid {
    padding: 16px 18px 4px;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.app-card {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 14px;
    border-radius: 14px;
    border: 1px solid rgba(231,229,228,0.9);
    background: rgba(250,250,249,0.75);
    text-decoration: none !important;
    color: var(--ink);
    box-shadow: var(--shadow-sm);
}

.app-card:hover {
    background: rgba(255,255,255,0.98);
    border-color: rgba(13,148,136,0.28);
    transform: translateY(-1px);
}

.app-card__icon {
    width: 34px;
    height: 34px;
    border-radius: 12px;
    background: radial-gradient(circle at 30% 30%, rgba(13,148,136,0.22), rgba(13,148,136,0.10) 55%, rgba(13,148,136,0.04));
    border: 1px solid rgba(13,148,136,0.16);
}

.app-card__label {
    font-weight: 700;
    letter-spacing: 0.02em;
    font-size: 16px;
}

.app-footer {
    margin-top: 12px;
    color: var(--ink-muted);
    font-size: 12px;
    padding: 0 6px;
}

@media (max-width: 980px) {
    .app-shell {
        grid-template-columns: 1fr;
    }

    .app-sidebar {
        order: 0;
    }

    .app-main {
        order: 1;
    }

    .app-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 560px) {
    body::before {
        width: 0;
    }

    .app-header__inner {
        padding: 12px 14px;
    }

    .app-shell {
        padding: 14px;
        gap: 14px;
    }

    .app-grid {
        grid-template-columns: 1fr;
    }
}