:root {
    --canvas: #f7f7f4;
    --canvas-soft: #fafaf7;
    --surface-card: #ffffff;
    --surface-strong: #e6e5e0;
    --hairline: #e6e5e0;
    --hairline-soft: #efeee8;
    --hairline-strong: #cfcdc4;
    --ink: #26251e;
    --body: #5a5852;
    --muted: #807d72;
    --primary: #f54e00;
    --primary-active: #d04200;
    --on-primary: #ffffff;
    --thinking: #dfa88f;
    --grep: #9fc9a2;
    --read: #9fbbe0;
    --edit: #c0a8dd;
    --done: #c08532;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--canvas);
    color: var(--body);
    font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 16px;
    line-height: 1.55;
}

img {
    display: block;
    max-width: 100%;
}

a {
    color: inherit;
    text-decoration: none;
}

h1,
h2,
h3 {
    color: var(--ink);
    font-weight: 400;
    letter-spacing: -0.018em;
    line-height: 1.12;
    margin: 0;
}

h1 {
    font-size: clamp(2.25rem, 12vw, 4.8rem);
}

h2 {
    font-size: clamp(1.8rem, 7vw, 2.4rem);
}

h3 {
    font-size: 1.35rem;
}

p {
    margin: 0;
}

.site-header {
    align-items: center;
    border-bottom: 1px solid var(--hairline);
    display: flex;
    gap: 16px;
    justify-content: space-between;
    min-height: 64px;
    padding: 12px 20px;
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(247, 247, 244, 0.96);
}

.brand {
    align-items: center;
    color: var(--ink);
    display: inline-flex;
    font-size: 0.95rem;
    font-weight: 600;
    gap: 10px;
}

.brand-mark {
    align-items: center;
    background: var(--primary);
    border-radius: 8px;
    color: var(--on-primary);
    display: inline-flex;
    font-size: 0.78rem;
    height: 32px;
    justify-content: center;
    letter-spacing: 0.02em;
    text-transform: uppercase;
    width: 32px;
}

.nav-toggle {
    background: var(--surface-card);
    border: 1px solid var(--hairline-strong);
    border-radius: 8px;
    color: var(--ink);
    cursor: pointer;
    min-height: 40px;
    padding: 8px 14px;
}

.primary-nav {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: 12px;
    display: none;
    flex-direction: column;
    gap: 4px;
    left: 20px;
    padding: 10px;
    position: absolute;
    right: 20px;
    top: 70px;
}

.primary-nav.is-open {
    display: flex;
}

.primary-nav a {
    border-radius: 8px;
    color: var(--body);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 10px 12px;
}

.primary-nav a[aria-current="page"] {
    background: var(--surface-strong);
    color: var(--ink);
}

main {
    overflow: hidden;
}

.hero,
.page-hero,
.editorial-band,
.related-section,
.site-footer,
.breadcrumb {
    margin-inline: auto;
    max-width: 1200px;
    padding-inline: 20px;
}

.hero {
    display: grid;
    gap: 32px;
    padding-block: 56px 40px;
}

.hero-copy {
    display: grid;
    gap: 20px;
    max-width: 880px;
}

.hero-copy p,
.page-hero p {
    font-size: clamp(1.05rem, 2.5vw, 1.25rem);
    max-width: 720px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.button-primary,
.button-secondary {
    align-items: center;
    border-radius: 8px;
    display: inline-flex;
    font-size: 0.9rem;
    font-weight: 500;
    justify-content: center;
    min-height: 40px;
    padding: 10px 18px;
}

.button-primary {
    background: var(--primary);
    color: var(--on-primary);
}

.button-primary:active {
    background: var(--primary-active);
}

.button-secondary {
    background: var(--surface-card);
    border: 1px solid var(--hairline-strong);
    color: var(--ink);
}

.section-kicker,
.card-kicker {
    color: var(--primary);
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.magazine-grid {
    display: grid;
    gap: 16px;
}

.feature-card,
.article-card,
.related-card,
.toc,
.note-card,
.check-card,
.faq-card,
.image-card,
.timeline-panel {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: 12px;
}

.feature-card,
.article-card,
.note-card,
.check-card,
.faq-card,
.timeline-panel {
    display: grid;
    gap: 14px;
    padding: 22px;
}

.feature-card a,
.article-card a,
.related-card span {
    color: var(--ink);
    font-weight: 600;
}

.image-card {
    margin: 0;
    overflow: hidden;
}

.image-card img {
    aspect-ratio: 16 / 10;
    object-fit: cover;
    width: 100%;
}

.image-card figcaption {
    color: var(--muted);
    font-size: 0.78rem;
    padding: 10px 12px;
}

.editorial-band,
.related-section {
    display: grid;
    gap: 24px;
    padding-block: 56px;
}

.section-heading {
    display: grid;
    gap: 12px;
    max-width: 760px;
}

.split-layout {
    display: grid;
    gap: 24px;
}

.content-flow {
    display: grid;
    gap: 18px;
    max-width: 760px;
}

.content-flow ul {
    display: grid;
    gap: 10px;
    margin: 0;
    padding-left: 20px;
}

.toc {
    display: grid;
    gap: 10px;
    padding: 18px;
}

.toc a {
    border-top: 1px solid var(--hairline-soft);
    color: var(--ink);
    padding-top: 10px;
}

.breadcrumb {
    align-items: center;
    color: var(--muted);
    display: flex;
    flex-wrap: wrap;
    font-size: 0.88rem;
    gap: 8px;
    padding-top: 28px;
}

.breadcrumb a {
    color: var(--ink);
}

.page-hero {
    display: grid;
    gap: 16px;
    padding-block: 42px 34px;
}

.timeline-list {
    display: grid;
    gap: 12px;
}

.timeline-item {
    align-items: start;
    border-top: 1px solid var(--hairline-soft);
    display: grid;
    gap: 8px;
    padding-top: 14px;
}

.timeline-pill {
    border-radius: 999px;
    color: var(--ink);
    display: inline-flex;
    font-size: 0.68rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    padding: 4px 10px;
    text-transform: uppercase;
    width: fit-content;
}

.timeline-pill.thinking {
    background: var(--thinking);
}

.timeline-pill.read {
    background: var(--read);
}

.timeline-pill.edit {
    background: var(--edit);
}

.timeline-pill.done {
    background: var(--done);
    color: var(--on-primary);
}

.check-filter {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.filter-button {
    background: var(--surface-card);
    border: 1px solid var(--hairline-strong);
    border-radius: 999px;
    color: var(--ink);
    cursor: pointer;
    min-height: 40px;
    padding: 8px 14px;
}

.filter-button.is-active {
    background: var(--ink);
    color: var(--canvas);
}

.check-grid,
.related-grid {
    display: grid;
    gap: 14px;
}

.check-card[data-hidden="true"] {
    display: none;
}

.faq-card details {
    border-top: 1px solid var(--hairline-soft);
    padding-top: 12px;
}

.faq-card summary {
    color: var(--ink);
    cursor: pointer;
    font-weight: 600;
    min-height: 40px;
}

.related-card {
    display: grid;
    gap: 8px;
    padding: 18px;
}

.related-card small {
    color: var(--body);
    font-size: 0.9rem;
}

.site-footer {
    border-top: 1px solid var(--hairline);
    display: grid;
    gap: 24px;
    padding-block: 48px;
}

.footer-title {
    color: var(--ink);
    font-weight: 600;
    margin-bottom: 8px;
}

.site-footer nav {
    display: grid;
    gap: 8px;
}

@media (min-width: 768px) {
    .site-header {
        padding-inline: 32px;
    }

    .nav-toggle {
        display: none;
    }

    .primary-nav {
        align-items: center;
        background: transparent;
        border: 0;
        display: flex;
        flex-direction: row;
        gap: 2px;
        padding: 0;
        position: static;
    }

    .hero,
    .page-hero,
    .editorial-band,
    .related-section,
    .site-footer,
    .breadcrumb {
        padding-inline: 32px;
    }

    .hero,
    .editorial-band,
    .related-section {
        padding-block: 80px;
    }

    .magazine-grid,
    .check-grid,
    .related-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .split-layout {
        align-items: start;
        grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    }

    .site-footer {
        grid-template-columns: 1.2fr 1fr;
    }
}