/* ===========================
   Course 06 — Квазиэксперименты
   Depends on: /assets/base.css (tokens)
   =========================== */
@import url("/assets/base.css");

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

body {
    font-family: var(--font-sans);
    line-height: var(--lh-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    padding: var(--space-2xl) var(--space-md);
}

.container {
    max-width: var(--max-container);
    margin: 0 auto;
}

/* ── Navigation ── */

.breadcrumbs {
    font-size: 0.85rem;
    color: var(--color-text-faint);
    margin-bottom: var(--space-md);
}
.breadcrumbs a {
    color: var(--color-text-muted);
    text-decoration: none;
    transition: color var(--t-default);
}
.breadcrumbs a:hover { color: var(--color-text); }

.back-to-home {
    display: inline-block;
    margin-bottom: var(--space-md);
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color var(--t-default);
}
.back-to-home:hover { color: var(--color-text); }

/* ── Typography ── */

h1 {
    font-size: 2rem;
    font-weight: 400;
    margin-bottom: var(--space-sm);
    color: var(--color-text);
}
h2 {
    font-size: 1.3rem;
    font-weight: 400;
    margin-top: var(--space-2xl);
    margin-bottom: var(--space-md);
    color: var(--color-text);
    padding-bottom: 0.3rem;
    border-bottom: 1px solid var(--color-border);
    scroll-margin-top: 2rem;
}
h2:first-of-type { margin-top: 0; }
h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--color-text);
    scroll-margin-top: 2rem;
}
h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-top: 1rem;
    margin-bottom: 0.35rem;
    color: #444;
}
p {
    font-size: 0.93rem;
    line-height: 1.65;
    margin-bottom: 0.75rem;
}
ul, ol {
    font-size: 0.93rem;
    line-height: 1.65;
    padding-left: 1.25rem;
    margin-bottom: 0.75rem;
}
li { margin-bottom: 0.25rem; }

.kicker {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-accent);
    margin-bottom: var(--space-sm);
}
.subtitle {
    font-size: 1rem;
    font-weight: 400;
    color: var(--color-text-muted);
    margin-bottom: var(--space-xl);
    font-style: italic;
    max-width: 700px;
}
section { margin-bottom: 2.5rem; }

/* ── TL;DR block ── */
.tldr {
    background: var(--color-bg-subtle);
    border-left: 3px solid var(--color-border);
    padding: 0.75rem 1rem;
    margin-bottom: 1rem;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.tldr p { margin-bottom: 0.25rem; font-size: 0.88rem; color: #444; }
.tldr strong { color: var(--color-text); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.04em; }

/* ── Tables ── */
table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
    margin-bottom: 1rem;
}
th, td {
    text-align: left;
    padding: 0.5rem 0.75rem;
    border-bottom: 1px solid var(--color-border);
    vertical-align: top;
}
th {
    font-weight: 600;
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--color-text-muted);
    background: var(--color-bg-subtle);
}
td { color: var(--color-text); }

/* ── Code blocks ── */
pre {
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 0.75rem 1rem;
    overflow-x: auto;
    margin-bottom: 1rem;
    font-size: 0.82rem;
    line-height: 1.5;
}
code {
    font-family: 'SF Mono', 'Menlo', 'Monaco', monospace;
    font-size: 0.82rem;
}
p code, li code, td code {
    background: rgba(0,0,0,.04);
    padding: 0.1rem 0.35rem;
    border-radius: 3px;
}

/* ── Decision tree ── */
.decision-tree {
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    margin-bottom: 1.5rem;
}
.decision-tree h3 { margin-top: 0; }
.dt-row {
    display: flex;
    gap: 0.5rem;
    align-items: baseline;
    padding: 0.35rem 0;
    font-size: 0.88rem;
    border-bottom: 1px solid rgba(0,0,0,.06);
}
.dt-row:last-child { border-bottom: none; }
.dt-cond { flex: 1; color: #444; }
.dt-arrow { color: #999; font-size: 0.75rem; }
.dt-method { font-weight: 600; color: var(--color-text); min-width: 140px; }

/* ── Interview Q&A ── */
.qa-list { list-style: none; padding-left: 0; counter-reset: qa; }
.qa-item {
    padding: 0.6rem 0;
    border-bottom: 1px solid rgba(0,0,0,.06);
    font-size: 0.88rem;
}
.qa-item:last-child { border-bottom: none; }
.qa-q { font-weight: 600; color: var(--color-text); margin-bottom: 0.2rem; }
.qa-q::before { counter-increment: qa; content: counter(qa) ". "; color: #999; }
.qa-a { color: #555; line-height: 1.55; }

/* ── Red flags ── */
.red-flags {
    background: rgba(220,38,38,.04);
    border-left: 3px solid rgba(220,38,38,.35);
    padding: 0.75rem 1rem;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    margin-bottom: 1rem;
}
.red-flags ul { margin-bottom: 0; }
.red-flags li { font-size: 0.88rem; color: #555; }

/* ── Case cards ── */
.case-card {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    margin-bottom: 1rem;
    background: var(--color-bg);
}
.case-card h4 { margin-top: 0; color: var(--color-text); font-size: 0.95rem; }
.case-meta {
    font-size: 0.72rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: #999;
    margin-bottom: 0.35rem;
}

/* ── details/summary ── */
details {
    margin-bottom: 0.75rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 0;
}
summary {
    padding: 0.5rem 0.75rem;
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--color-text);
    cursor: pointer;
    list-style: none;
}
summary::before { content: "\25B8 "; color: #999; }
details[open] summary::before { content: "\25BE "; }
details > div {
    padding: 0 0.75rem 0.75rem;
    font-size: 0.88rem;
    color: #444;
    line-height: 1.6;
}
details > div p { font-size: 0.88rem; }

/* ── Key terms bar ── */
.key-terms {
    display: flex;
    gap: 0.35rem;
    flex-wrap: wrap;
    align-items: center;
    margin-bottom: 1.5rem;
}
.key-terms-label {
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: #999;
    margin-right: 0.25rem;
}

/* ── Glossary links ── */
.glossary-link {
    font-size: 0.82rem;
    color: var(--color-accent);
    text-decoration: none;
    border-bottom: 1px dotted rgba(0,113,227,.35);
}
.glossary-link:hover { border-bottom-style: solid; }

.todo-list {
    background: var(--color-bg-subtle);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 0.75rem 1rem;
}
.todo-list code {
    font-size: 0.82rem;
    background: rgba(0,0,0,.04);
    padding: 0.1rem 0.3rem;
    border-radius: 3px;
}

/* ── Module cards grid (landing page) ── */
.modules-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-lg);
    margin-bottom: var(--space-2xl);
}
.module-card {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    background: var(--color-bg-subtle);
}
.module-title {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: var(--space-sm);
    color: var(--color-text);
}
.module-key-idea {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    font-style: italic;
    margin-bottom: 0.75rem;
    line-height: 1.5;
}
.module-card-meta {
    font-size: 0.8rem;
    color: var(--color-text-faint);
    margin-top: 0.75rem;
}
.module-card-links {
    display: flex;
    gap: var(--space-sm);
    margin-top: var(--space-md);
    flex-wrap: wrap;
}
.module-card-link {
    display: inline-block;
    padding: 0.35rem 0.75rem;
    font-size: 0.85rem;
    color: var(--color-text-muted);
    text-decoration: none;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: border-color var(--t-default), color var(--t-default);
}
.module-card-link:hover {
    border-color: var(--color-border-hover);
    color: var(--color-text);
}
.module-card-link-primary {
    color: var(--color-text);
    border-color: var(--color-accent);
    font-weight: 500;
}
.module-card-link-primary:hover {
    background: var(--color-accent);
    color: var(--color-bg);
}

/* ── Intro section (landing page) ── */
.intro {
    max-width: var(--max-content);
    margin-bottom: var(--space-2xl);
}
.intro p {
    font-size: 0.95rem;
    line-height: var(--lh-loose);
    color: var(--color-text);
    margin-bottom: var(--space-md);
}

/* ── Related / footer ── */
.related-section {
    margin-top: var(--space-3xl);
    margin-bottom: var(--space-2xl);
    padding-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
}
.related-links {
    list-style: none;
    padding-left: 0;
}
.related-links li { margin-bottom: 0.75rem; }
.related-links a {
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color var(--t-default);
}
.related-links a:hover { color: var(--color-text); }

.footer-note {
    margin-top: var(--space-3xl);
    padding-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
    font-size: 0.85rem;
    color: var(--color-text-muted);
    font-style: italic;
}

/* ── Module bottom navigation ── */
.module-nav {
    margin: var(--space-2xl) 0 var(--space-xl) 0;
    padding: var(--space-md) 0;
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
}
.module-nav a {
    display: inline-block;
    padding: var(--space-sm) var(--space-md);
    color: var(--color-text-muted);
    text-decoration: none;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    transition: border-color var(--t-default), color var(--t-default);
}
.module-nav a:hover {
    border-color: var(--color-border-hover);
    color: var(--color-text);
}
.module-nav .nav-disabled {
    color: #ccc;
    border-color: #f0f0f0;
    cursor: default;
    pointer-events: none;
}