:root {
    --bg: #faf7f2;
    --surface: #fffdf9;
    --ink: #1f2933;
    --muted: #5d6b78;
    --line: #e6ded2;
    --accent: #b4532a;
    --accent-soft: #f6e7dc;
    --ok: #2f6f4f;
    --ok-soft: #e2efe7;
    --fail: #a33a2a;
    --fail-soft: #f7e4e0;
    --radius: 14px;
    --serif: ui-serif, Georgia, "Times New Roman", serif;
    --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    --mono: ui-monospace, "SF Mono", "Cascadia Code", Menlo, monospace;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #16191c;
        --surface: #1e2327;
        --ink: #e9e6e0;
        --muted: #a5afb8;
        --line: #2e353b;
        --accent: #e08a5f;
        --accent-soft: #33251d;
        --ok: #7cc39d;
        --ok-soft: #1c2c24;
        --fail: #e58b7c;
        --fail-soft: #33201d;
    }
}

* {
    box-sizing: border-box;
}

html {
    color-scheme: light dark;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: var(--serif);
    font-size: 1.06rem;
    line-height: 1.65;
    -webkit-text-size-adjust: 100%;
}

a {
    color: var(--accent);
    text-decoration-thickness: 1px;
    text-underline-offset: 3px;
}

.site-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    max-width: 72ch;
    margin: 0 auto;
    padding: 1.25rem 1.25rem 0.5rem;
    font-family: var(--sans);
    font-size: 0.92rem;
}

.brand {
    font-family: var(--serif);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--ink);
    text-decoration: none;
    letter-spacing: 0.01em;
}

.who {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--muted);
}

main {
    max-width: 72ch;
    margin: 0 auto;
    padding: 1rem 1.25rem 4rem;
}

.site-footer {
    max-width: 72ch;
    margin: 0 auto;
    padding: 1.5rem 1.25rem 2.5rem;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.82rem;
    border-top: 1px solid var(--line);
}

.panel {
    padding-top: 1rem;
}

.panel.narrow {
    max-width: 60ch;
}

.eyebrow {
    margin: 0 0 0.25rem;
    color: var(--accent);
    font-family: var(--sans);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

h1 {
    margin: 0 0 0.6rem;
    font-size: clamp(1.7rem, 4vw, 2.3rem);
    line-height: 1.2;
    font-weight: 600;
}

h2 {
    margin: 1.75rem 0 0.5rem;
    font-size: 1.3rem;
    line-height: 1.3;
    font-weight: 600;
}

.lede {
    margin: 0 0 1.25rem;
    color: var(--muted);
    font-size: 1.08rem;
}

.hint {
    margin-top: 1rem;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.86rem;
}

.stack {
    display: grid;
    gap: 0.5rem;
    margin: 1.5rem 0;
}

label {
    font-family: var(--sans);
    font-size: 0.9rem;
    color: var(--muted);
}

input[type="text"] {
    width: 100%;
    padding: 0.8rem 0.9rem;
    border: 1px solid var(--line);
    border-radius: 10px;
    background: var(--surface);
    color: var(--ink);
    font-family: var(--sans);
    font-size: 1rem;
}

input[type="text"]:focus-visible,
button:focus-visible,
.button:focus-visible,
.option:focus-within {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

button,
.button {
    display: inline-block;
    padding: 0.65rem 1.2rem;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: var(--surface);
    color: var(--ink);
    font-family: var(--sans);
    font-size: 0.92rem;
    text-decoration: none;
    cursor: pointer;
}

button.primary,
.button.primary {
    border-color: transparent;
    background: var(--accent);
    color: #fff;
}

button.link {
    padding: 0;
    border: 0;
    background: none;
    color: var(--muted);
    text-decoration: underline;
}

.inline {
    display: inline;
}

/* Программа */

.progress {
    margin: 1.5rem 0 2rem;
}

.progress-text {
    font-family: var(--sans);
    font-size: 0.92rem;
    color: var(--muted);
    margin-bottom: 0.5rem;
}

.progress-text strong {
    color: var(--ink);
}

.progress-track {
    height: 8px;
    border-radius: 999px;
    background: var(--line);
    overflow: hidden;
}

.progress-track span {
    display: block;
    height: 100%;
    background: var(--accent);
}

.lesson-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.6rem;
}

.lesson {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.9rem 1rem;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--surface);
}

.lesson-main {
    display: flex;
    align-items: center;
    gap: 0.9rem;
}

.lesson-number {
    display: grid;
    place-items: center;
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    background: var(--accent-soft);
    color: var(--accent);
    font-family: var(--sans);
    font-size: 0.9rem;
    font-weight: 600;
}

.lesson.studied .lesson-number {
    background: var(--ok-soft);
    color: var(--ok);
}

.lesson-title {
    font-weight: 600;
    text-decoration: none;
    color: var(--ink);
}

.lesson-title:hover {
    text-decoration: underline;
}

.lesson-meta {
    margin: 0.15rem 0 0;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.82rem;
}

.crumbs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.85rem;
}

/* Урок */

.lesson-body {
    max-width: 68ch;
}

.slide {
    margin: 0 0 1.75rem;
    padding: 1.25rem 1.4rem;
    border: 1px solid var(--line);
    border-left: 3px solid var(--accent);
    border-radius: var(--radius);
    background: var(--surface);
}

.slide h2 {
    margin-top: 0;
}

.block {
    margin: 0.75rem 0;
}

.block-text {
    white-space: pre-wrap;
}

.block-code {
    padding: 0.9rem 1rem;
    border-radius: 10px;
    background: #1f2328;
    color: #e6e1d8;
    overflow-x: auto;
    font-family: var(--mono);
    font-size: 0.88rem;
    line-height: 1.55;
}

.block-math {
    overflow-x: auto;
    padding: 0.35rem 0;
}

.block-image img {
    max-width: 100%;
    border-radius: 10px;
}

.block-image figcaption {
    margin-top: 0.4rem;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.82rem;
}

.block-check {
    margin: 1rem 0 0.25rem;
    padding: 1rem 1.1rem;
    border-radius: var(--radius);
    background: var(--accent-soft);
}

.check-label {
    margin: 0 0 0.35rem;
    color: var(--accent);
    font-family: var(--sans);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.check-prompt {
    margin: 0 0 0.5rem;
    font-weight: 600;
}

.check-options {
    margin: 0 0 0.5rem;
    padding-left: 1.2rem;
}

.check-note {
    margin: 0;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.8rem;
}

.lesson-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}

/* Квиз */

.quiz-form {
    margin-top: 1.5rem;
    display: grid;
    gap: 1.25rem;
}

.question {
    margin: 0;
    padding: 1.1rem 1.2rem;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--surface);
}

.question legend {
    padding: 0 0.35rem;
    font-weight: 600;
    font-size: 1.02rem;
}

.question-number {
    display: inline-grid;
    place-items: center;
    width: 1.7rem;
    height: 1.7rem;
    margin-right: 0.35rem;
    border-radius: 50%;
    background: var(--accent-soft);
    color: var(--accent);
    font-family: var(--sans);
    font-size: 0.82rem;
}

.option {
    display: flex;
    align-items: flex-start;
    gap: 0.6rem;
    padding: 0.55rem 0.6rem;
    border-radius: 10px;
    cursor: pointer;
    font-family: var(--sans);
    font-size: 0.95rem;
    color: var(--ink);
}

.option:hover {
    background: var(--accent-soft);
}

.option input {
    margin-top: 0.25rem;
    accent-color: var(--accent);
}

.score {
    display: flex;
    align-items: baseline;
    gap: 0.75rem;
    margin: 1.25rem 0 1.75rem;
    padding: 1rem 1.2rem;
    border-radius: var(--radius);
}

.score.pass {
    background: var(--ok-soft);
}

.score.fail {
    background: var(--fail-soft);
}

.score-value {
    font-size: 2rem;
    font-weight: 600;
}

.score.pass .score-value {
    color: var(--ok);
}

.score.fail .score-value {
    color: var(--fail);
}

.score-label {
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.88rem;
}

.review {
    margin: 0;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 0.75rem;
}

.review-item {
    padding: 0.9rem 1.05rem;
    border-radius: var(--radius);
    border-left: 3px solid var(--line);
    background: var(--surface);
}

.review-item.ok {
    border-left-color: var(--ok);
}

.review-item.wrong {
    border-left-color: var(--fail);
}

.review-prompt {
    margin: 0 0 0.35rem;
    font-weight: 600;
}

.review-answer {
    margin: 0;
}

.review-item.wrong .review-answer {
    color: var(--fail);
}

.review-note {
    margin: 0.4rem 0 0;
    color: var(--muted);
    font-family: var(--sans);
    font-size: 0.85rem;
}

/* Опекун */

.table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.25rem 0;
    font-family: var(--sans);
    font-size: 0.92rem;
}

.table th,
.table td {
    padding: 0.65rem 0.5rem;
    border-bottom: 1px solid var(--line);
    text-align: left;
}

.table th {
    color: var(--muted);
    font-weight: 600;
    font-size: 0.8rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

@media (max-width: 560px) {
    .lesson {
        flex-direction: column;
        align-items: flex-start;
    }

    .lesson-actions {
        align-items: flex-start;
        flex-direction: column;
    }
}