:root {
    color-scheme: light;
    --bg: #ffffff;
    --surface: #ffffff;
    --surface-soft: #fafafa;
    --ink: #0f0f10;
    --ink-soft: #6b6b70;
    --line: #d4d4d4;
    --line-strong: #c0c0c0;
    --accent: #2f4ad0;
    --accent-soft: #eef1fc;
    --ok: #1f9d55;
    --ok-soft: #e7f6ec;
    --bad: #c53030;
    --bad-soft: #fdecec;
    --shadow-card: 0 8px 24px -12px rgba(15, 15, 16, 0.18);
    --shadow-focus: 0 0 0 4px rgba(15, 15, 16, 0.06);
    --shadow-toplink: 0 4px 14px -6px rgba(15, 15, 16, 0.12);
}

[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0c0c0e;
    --surface: #141418;
    --surface-soft: #1c1c21;
    --ink: #f5f5f7;
    --ink-soft: #9b9ba3;
    --line: #2e2e35;
    --line-strong: #44444c;
    --accent: #7c8fff;
    --accent-soft: #1c2244;
    --ok: #4ade80;
    --ok-soft: #102a1a;
    --bad: #f87171;
    --bad-soft: #2c1414;
    --shadow-card: 0 8px 24px -8px rgba(0, 0, 0, 0.6);
    --shadow-focus: 0 0 0 4px rgba(124, 143, 255, 0.18);
    --shadow-toplink: 0 4px 14px -6px rgba(0, 0, 0, 0.6);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "Inter", "Helvetica Neue", Helvetica, Arial, sans-serif;
    font-size: 16px;
    line-height: 1.55;
    letter-spacing: -0.005em;
    -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
button, input { font: inherit; }
p { margin-top: 0; }
p:last-child { margin-bottom: 0; }
.page,
.practice-shell {
    width: min(1120px, calc(100% - 40px));
    margin: 0 auto;
    padding: 20px 0 80px;
}
.skip-link {
    position: absolute;
    left: 16px;
    top: 16px;
    z-index: 30;
    transform: translateY(-140%);
    background: var(--ink);
    color: var(--bg);
    padding: 10px 14px;
    border-radius: 999px;
    text-decoration: none;
    transition: transform 0.15s;
}
.skip-link:focus { transform: translateY(0); }

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    border-bottom: 1px solid var(--line);
    padding-bottom: 20px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; font-weight: 600; }
.brand-mark {
    display: inline-grid;
    place-items: center;
    width: 28px;
    height: 28px;
    border-radius: 8px;
    background: var(--ink);
    color: var(--bg);
}
.nav-actions { display: flex; align-items: center; gap: 10px; }
.nav-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    min-height: 38px;
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 0 12px;
    color: var(--ink-soft);
    font-size: 0.9rem;
}
.theme-toggle {
    display: inline-grid;
    place-items: center;
    width: 38px;
    height: 38px;
    border: 1px solid var(--line);
    border-radius: 50%;
    background: var(--surface-soft);
    color: var(--ink);
    cursor: pointer;
    font-size: 14px;
    padding: 0;
}
.theme-toggle:hover,
.theme-toggle:focus-visible {
    background: var(--accent-soft);
    border-color: var(--accent);
    color: var(--accent);
    outline: 0;
}
.theme-toggle-icon { display: none; }
[data-theme="dark"] .theme-toggle-icon-light { display: inline-block; }
:root:not([data-theme="dark"]) .theme-toggle-icon-dark { display: inline-block; }

.breadcrumb { margin: 16px 0; }
.breadcrumb a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 40px;
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 0 14px;
    color: var(--ink-soft);
    text-decoration: none;
}
.breadcrumb a:hover,
.breadcrumb a:focus-visible {
    border-color: var(--accent);
    color: var(--accent);
    background: var(--accent-soft);
    outline: 0;
}

.hero { padding: 16px 0 56px; max-width: 880px; }
.hero h1 { font-size: clamp(2.2rem, 7vw, 5rem); line-height: 1.05; margin: 0 0 12px; letter-spacing: -0.035em; }
.hero p { color: var(--ink-soft); font-size: 1.1rem; }
.practice-hero { padding: 16px 0 24px; }
.practice-hero h1 { font-size: clamp(1.8rem, 5vw, 2.4rem); line-height: 1.1; margin: 8px 0; letter-spacing: -0.03em; }
.practice-hero p { color: var(--ink-soft); }
.practice-hero-center { text-align: center; }
.eyebrow {
    margin: 0 0 8px;
    color: var(--accent);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.18em;
    text-transform: uppercase;
}

.search-wrap { display: flex; justify-content: center; margin-bottom: 32px; }
.hero-search { position: relative; width: min(520px, 100%); }
.hero-search-icon {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--ink-soft);
}
.hero-search-input {
    width: 100%;
    height: 56px;
    border: 1px solid var(--line-strong);
    border-radius: 14px;
    background: var(--surface);
    color: var(--ink);
    padding: 10px 18px 10px 48px;
}
.hero-search-input:focus {
    border-color: var(--ink);
    box-shadow: var(--shadow-focus);
    outline: 0;
}
.projects-head { display: flex; justify-content: space-between; align-items: end; gap: 16px; margin-bottom: 16px; }
.projects-head h2 { font-size: clamp(1.3rem, 2vw, 1.6rem); margin: 0; }
.projects-count { color: var(--ink-soft); font-size: 0.95rem; }
.grid {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 16px;
}
.card {
    border: 1px solid var(--line);
    border-radius: 16px;
    background: var(--surface);
    padding: 22px;
    transition: transform 0.15s, border-color 0.15s, box-shadow 0.15s;
}
.card a { display: block; color: inherit; text-decoration: none; }
.card:hover { transform: translateY(-2px); border-color: var(--ink); box-shadow: var(--shadow-card); }
.card-top { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.card-icon {
    display: inline-grid;
    place-items: center;
    width: 44px;
    height: 44px;
    border-radius: 12px;
    background: var(--accent-soft);
    color: var(--accent);
    font-size: 18px;
}
.card:hover .card-icon { background: var(--accent); color: var(--bg); }
.card-num { color: var(--ink-soft); font-size: 0.85rem; font-weight: 600; }
.card-arrow { margin-left: auto; color: var(--ink-soft); }
.card-tag {
    display: inline-block;
    color: var(--accent);
    font-size: 0.78rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    margin-bottom: 6px;
    text-transform: uppercase;
}
.card-title { font-size: clamp(1.5rem, 2.5vw, 1.85rem); margin: 0 0 8px; }
.card-desc { color: var(--ink-soft); margin: 0 0 16px; }
.card-foot { display: flex; flex-wrap: wrap; gap: 12px; color: var(--ink-soft); font-size: 0.9rem; }
.empty { color: var(--ink-soft); text-align: center; padding: 32px 0; }

.practice-card {
    display: grid;
    gap: 24px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: var(--surface);
    padding: clamp(20px, 4vw, 32px);
    margin-bottom: 16px;
}
.practice-card[hidden] { display: none; }
.practice-status { display: flex; flex-wrap: wrap; gap: 16px; color: var(--ink-soft); font-size: 0.9rem; }
.practice-status p { margin: 0; }
.reading-passage { display: grid; gap: 8px; }
.reading-passage p { margin: 0; font-size: 1.08rem; line-height: 1.7; }
.practice-question h2 { font-size: clamp(1.3rem, 3vw, 1.6rem); margin: 0; }
.answer-options { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
.answer-button,
.restart-button {
    min-height: 56px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: var(--surface);
    color: var(--ink);
    cursor: pointer;
    font-weight: 600;
    padding: 12px 16px;
    text-align: left;
    transition: background 0.15s, border-color 0.15s, color 0.15s, box-shadow 0.15s;
}
.restart-button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; text-align: center; }
.answer-button:hover,
.answer-button:focus-visible,
.restart-button:hover,
.restart-button:focus-visible {
    background: var(--accent-soft);
    border-color: var(--accent);
    color: var(--accent);
    box-shadow: var(--shadow-focus);
    outline: 0;
}
.answer-button:disabled { cursor: default; }
.answer-button.correct,
.answer-button.correct:hover,
.answer-button.correct:focus-visible {
    background: var(--ok-soft);
    border-color: var(--ok);
    color: var(--ok);
    box-shadow: none;
}
.answer-button.incorrect,
.answer-button.incorrect:hover,
.answer-button.incorrect:focus-visible {
    background: var(--bad-soft);
    border-color: var(--bad);
    color: var(--bad);
    box-shadow: none;
}
.next-button {
    background: var(--ink);
    border-color: var(--ink);
    color: var(--bg);
}
.next-button:hover,
.next-button:focus-visible {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg);
}
.next-button[hidden] { display: none; }
.sequence-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.feedback { color: var(--ink-soft); margin: 0; min-height: 1.4em; }

.story-map {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 12px;
}
.map-slot {
    display: grid;
    gap: 8px;
    min-height: 112px;
    border: 1px dashed var(--line);
    border-radius: 14px;
    background: var(--surface-soft);
    padding: 14px;
}
.map-label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--ink-soft);
    font-size: 0.9rem;
    font-weight: 600;
}
.map-slot strong { color: var(--ink); line-height: 1.35; }
.map-slot.map-complete { border-style: solid; border-color: var(--ok); background: var(--ok-soft); }
.map-slot.map-review { border-style: solid; border-color: var(--bad); background: var(--bad-soft); }

.summary-card[hidden] { display: none; }
.summary-banner {
    margin: 0;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: var(--surface-soft);
    padding: 16px 20px;
    font-weight: 600;
}
.summary-list {
    display: grid;
    gap: 10px;
    margin: 0;
    padding-left: 20px;
}
.summary-list li { color: var(--ink-soft); }
.summary-list strong { color: var(--ink); }

.foot {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
    border-top: 1px solid var(--line);
    padding-top: 24px;
    margin-top: 48px;
    color: var(--ink-soft);
    font-size: 0.9rem;
}

@media (max-width: 760px) {
    .grid,
    .answer-options,
    .story-map { grid-template-columns: 1fr; }
    .hero-search-input { height: 52px; }
    .foot { flex-direction: column; }
    .nav { align-items: flex-start; }
    .nav-actions { flex-wrap: wrap; justify-content: flex-end; }
}