:root {
    color-scheme: light;
    --color-bg: #f7f6f2;
    --color-surface: #ffffff;
    --color-surface-muted: #efeee9;
    --color-text: #171717;
    --color-text-muted: #686868;
    --color-text-subtle: #929292;
    --color-border: #deddd7;
    --color-border-strong: #c9c7bf;
    --color-accent: #d97706;
    --color-accent-hover: #b45309;
    --color-success: #16803c;
    --color-warning: #a16207;
    --color-error: #b42318;
    --color-code-bg: #1c1c1c;
    --color-code-text: #ededed;
    --font-sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;
    --font-serif: "Source Serif 4", Georgia, serif;
    --container-max: 1200px;
    --content-max: 760px;
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;
    --space-5xl: 8rem;
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 10px;
    --shadow-sm: 0 1px 2px rgb(0 0 0 / 4%);
    --shadow-md: 0 8px 24px rgb(0 0 0 / 8%);
}

[data-theme="dark"] {
    color-scheme: dark;
    --color-bg: #111110;
    --color-surface: #191918;
    --color-surface-muted: #222220;
    --color-text: #f1f0eb;
    --color-text-muted: #a5a39b;
    --color-text-subtle: #77766f;
    --color-border: #32322f;
    --color-border-strong: #484842;
    --color-accent: #f59e0b;
    --color-accent-hover: #fbbf24;
    --color-success: #4ade80;
    --color-warning: #facc15;
    --color-error: #f87171;
    --color-code-bg: #0b0b0a;
    --color-code-text: #f1f1ed;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    background: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-sans);
    line-height: 1.6;
}

a { color: inherit; }

a,
button { transition: color 160ms ease, background-color 160ms ease, border-color 160ms ease, transform 160ms ease; }

a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 3px;
}

button { color: inherit; font: inherit; }

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.site-header,
.site-footer,
.site-main {
    width: min(100% - 2rem, var(--container-max));
    margin-inline: auto;
}

.site-header {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-lg);
    min-height: 4.5rem;
    border-bottom: 1px solid var(--color-border);
}

.site-brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 700;
    text-decoration: none;
}

.site-brand__mark {
    display: grid;
    width: 2rem;
    height: 2rem;
    place-items: center;
    border: 1px solid var(--color-border-strong);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.7rem;
}

.site-brand__name { letter-spacing: -0.02em; }

.site-nav {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.site-nav__link {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    text-decoration: none;
}

.site-nav__link:hover,
.site-nav__link:focus-visible { color: var(--color-accent); }

.site-nav__link--external { font-family: var(--font-mono); font-size: 0.75rem; }

.site-nav__toggle,
.theme-toggle {
    border: 0;
    background: transparent;
    cursor: pointer;
}

.site-nav__toggle { display: none; font-size: 1.25rem; }
.theme-toggle {
    display: inline-flex;
    width: 2.75rem;
    min-height: 2.75rem;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) var(--space-md);
    border: 1px solid var(--color-border-strong);
    border-radius: var(--radius-sm);
    background: var(--color-surface);
    cursor: pointer;
    justify-content: center;
}
.theme-toggle:hover { border-color: var(--color-accent); color: var(--color-accent); }
.theme-toggle__icon { font-size: 1.5rem; line-height: 1; }

.site-main { min-height: 70vh; }

.blog-page { padding-block: var(--space-4xl); }
.blog-page > h1 { max-width: 18ch; }
.blog-layout { display: grid; grid-template-columns: 13rem minmax(0, 1fr); gap: var(--space-3xl); margin-top: var(--space-2xl); }
.blog-sidebar { display: grid; align-content: start; gap: var(--space-sm); }
.blog-sidebar h2 { margin: 0 0 var(--space-sm); font-size: 1rem; }
.blog-sidebar a { color: var(--color-text-muted); text-decoration: none; }
.blog-sidebar a:hover { color: var(--color-accent); }
.article-list { display: grid; gap: var(--space-lg); margin-top: var(--space-xl); }
.article-card { padding: var(--space-xl); border: 1px solid var(--color-border); background: var(--color-surface); }
.article-card h2 { margin-block: var(--space-sm); font-size: 1.5rem; }
.article-card h2 a { text-decoration: none; }
.text-link { color: var(--color-accent); }
.article-detail { max-width: var(--content-max); padding-block: var(--space-4xl); }
.article-detail h1 { max-width: none; }
.prose { margin-top: var(--space-2xl); }
.search-page { max-width: var(--content-max); padding-block: var(--space-4xl); }
.search-page > h1 { max-width: 20ch; }
.search-form { display: flex; gap: var(--space-sm); margin-top: var(--space-2xl); }
.search-form input { flex: 1; min-height: 2.75rem; padding: 0.65rem 0.8rem; border: 1px solid var(--color-border-strong); background: var(--color-surface); color: var(--color-text); font: inherit; }
.search-filters { display: flex; flex-wrap: wrap; gap: var(--space-sm); margin-block: var(--space-xl); }
.search-filters a { padding: 0.35rem 0.65rem; border: 1px solid var(--color-border); text-decoration: none; }
.search-filters a:hover { border-color: var(--color-accent); color: var(--color-accent); }
.search-results { display: grid; gap: var(--space-md); }
.search-results__count { color: var(--color-text-muted); }
.search-result { padding: var(--space-lg); border: 1px solid var(--color-border); background: var(--color-surface); }
.search-result h2 { margin-block: var(--space-xs) var(--space-sm); font-size: 1.35rem; }
.search-result h2 a { text-decoration: none; }
.search-result p { color: var(--color-text-muted); }

/* — Certificates — */
.cert-overview { margin-top: var(--space-md); max-width: 65ch; }
.cert-filters {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-top: var(--space-xl);
    margin-bottom: var(--space-2xl);
}
.cert-filters a { padding: 0.35rem 0.65rem; border: 1px solid var(--color-border); text-decoration: none; color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.8rem; transition: border-color 150ms, color 150ms; }
.cert-filters a:hover,
.cert-filters a.is-active { border-color: var(--color-accent); color: var(--color-accent); }
.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(20rem, 1fr));
    gap: var(--space-xl);
    list-style: none;
    padding: 0;
    margin: var(--space-lg) 0 0;
}
.cert-card { border: 1px solid var(--color-border); background: var(--color-surface); box-shadow: var(--shadow-sm); overflow: hidden; display: flex; flex-direction: column; transition: box-shadow 150ms, border-color 150ms, transform 150ms; }
.cert-card:hover { border-color: var(--color-accent); box-shadow: var(--shadow-md, 0 4px 14px rgb(0 0 0 / .15)); transform: translateY(-2px); }
.cert-card__link { display: flex; flex-direction: column; height: 100%; text-decoration: none; color: inherit; }
.cert-card__figure { margin: 0; display: flex; flex-direction: column; flex: 1; }
.cert-card__media { background: var(--color-surface-muted); border-bottom: 1px solid var(--color-border); overflow: hidden; display: flex; align-items: center; justify-content: center; height: 14rem; }
.cert-card__img { display: block; max-width: 100%; max-height: 100%; object-fit: contain; padding: var(--space-sm); transition: transform 200ms ease; }
.cert-card:hover .cert-card__img { transform: scale(1.02); }
.cert-card__caption { display: flex; flex-direction: column; flex: 1; gap: var(--space-xs); padding: var(--space-lg); }
.cert-card__meta { display: flex; align-items: center; justify-content: space-between; gap: var(--space-sm); }
.cert-card__category { font-family: var(--font-mono); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--color-accent); }
.cert-card__date { font-family: var(--font-mono); font-size: 0.75rem; color: var(--color-text-muted); }
.cert-card__title { font-size: 1.15rem; font-weight: 600; color: var(--color-text); margin: var(--space-xs) 0 0; line-height: 1.3; }
.cert-card__issuer { margin: 0; font-size: 0.85rem; color: var(--color-text-muted); }
.cert-card__footer { margin-top: auto; padding-top: var(--space-md); }
.cert-card__footer .text-link { font-size: 0.85rem; font-weight: 500; }

/* — Certificate Detail — */
.cert-detail { max-width: 100%; padding-block: var(--space-4xl); }
.cert-detail__header { max-width: none; padding-bottom: var(--space-2xl); }
.cert-detail__header h1 {
    max-width: none;
    font-size: clamp(1.65rem, 3vw, 2.25rem);
    line-height: 1.2;
    margin-block: var(--space-xs) var(--space-md);
    letter-spacing: -0.02em;
}
.cert-detail__layout {
    display: grid;
    grid-template-columns: minmax(14rem, 18rem) minmax(0, 1fr);
    gap: var(--space-3xl);
    border-top: 1px solid var(--color-border);
    padding-top: var(--space-2xl);
}
.cert-detail__metadata {
    align-self: start;
    position: sticky;
    top: var(--space-xl);
    display: flex;
    flex-direction: column;
    gap: var(--space-xl);
}
.cert-detail__preview {
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    padding: var(--space-md);
}
.cert-detail__preview-link { display: block; text-decoration: none; color: inherit; }
.cert-detail__preview-img {
    display: block;
    width: 100%;
    max-height: 16rem;
    object-fit: contain;
    background: var(--color-surface-muted);
    border: 1px solid var(--color-border);
}
.cert-detail__preview-hint {
    display: block;
    margin-top: var(--space-xs);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--color-accent);
    text-align: right;
}
.cert-detail__content {
    min-width: 0;
    width: 100%;
}
.cert-detail__content .markdown-content {
    max-width: none;
    width: 100%;
    line-height: 1.7;
}
.cert-detail__content .markdown-content h1 {
    max-width: none;
    font-size: clamp(1.35rem, 2.2vw, 1.75rem);
    line-height: 1.25;
    margin-top: var(--space-lg);
    margin-bottom: var(--space-xs);
    letter-spacing: -0.02em;
}
.cert-detail__content .markdown-content h2 {
    max-width: none;
    font-size: clamp(1.15rem, 1.8vw, 1.35rem);
    line-height: 1.3;
    margin-top: var(--space-xl);
    margin-bottom: var(--space-xs);
    letter-spacing: -0.01em;
}
.cert-detail__content .markdown-content h3 {
    max-width: none;
    font-size: 1.05rem;
    line-height: 1.35;
    margin-top: var(--space-md);
    margin-bottom: var(--space-xs);
}
.cert-detail__content .markdown-content p,
.cert-detail__content .markdown-content ul,
.cert-detail__content .markdown-content ol,
.cert-detail__content .markdown-content blockquote {
    max-width: none;
}
.cert-detail__content .markdown-content img {
    max-width: 100%;
    max-height: 28rem;
    object-fit: contain;
    border: 1px solid var(--color-border);
    background: var(--color-surface-muted);
    padding: var(--space-xs);
}

.hero {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(16rem, 22rem);
    gap: var(--space-4xl);
    align-items: center;
    padding-block: var(--space-5xl);
}

.hero__content { max-width: 42rem; }

.hero__system {
    padding: var(--space-xl);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    font-family: var(--font-mono);
    box-shadow: var(--shadow-sm);
}

.eyebrow,
.metadata,
.section-label,
.empty-state__label {
    color: var(--color-text-muted);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

h1,
h2,
h3 { line-height: 1.1; letter-spacing: -0.03em; }

h1 {
    max-width: 13ch;
    margin-block: var(--space-sm) var(--space-lg);
    font-size: clamp(2.5rem, 7vw, 5rem);
}
h1.blog-heading {
    font-size: clamp(0.9rem, 6vw, 1.5rem);
    max-width: 20ch;
}
h2 { max-width: 24ch; margin-block: var(--space-sm) var(--space-xl); font-size: clamp(1.75rem, 4vw, 2.5rem); }

.lede { color: var(--color-text-muted); font-size: 0.9125rem; }

.hero__actions { display: flex; flex-wrap: wrap; gap: var(--space-sm); margin-top: var(--space-xl); }

.button {
    display: inline-flex;
    min-height: 2.75rem;
    align-items: center;
    gap: var(--space-sm);
    justify-content: center;
    padding: 0.65rem 1rem;
    border: 1px solid var(--color-border-strong);
    border-radius: var(--radius-sm);
    text-decoration: none;
}

.button:hover { border-color: var(--color-accent); color: var(--color-accent); }
.button--primary { border-color: var(--color-text); background: var(--color-text); color: var(--color-bg); }
.button--primary:hover { border-color: var(--color-accent); background: var(--color-accent); color: #171717; }
.button--secondary { background: transparent; }

.metadata-list { display: grid; gap: var(--space-sm); margin: var(--space-lg) 0 0; }
.metadata-list div { display: flex; justify-content: space-between; gap: var(--space-md); }
.metadata-list dt { color: var(--color-text-muted); }
.metadata-list dd { margin: 0; }
.metadata-list__stack { text-align: right; }

.section-block { padding-block: var(--space-4xl); border-top: 1px solid var(--color-border); }
.empty-state { max-width: var(--content-max); padding: var(--space-xl); border: 1px dashed var(--color-border-strong); background: var(--color-surface-muted); }
.empty-state p:last-child { max-width: 55ch; margin-bottom: 0; color: var(--color-text-muted); }
.page-intro { max-width: var(--content-max); padding-block: var(--space-4xl); }
.page-intro h1 { max-width: 16ch; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: var(--space-xl); }
.section-heading h2 { margin-bottom: 0; }
.filter-label { color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.8rem; }
.project-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-lg); margin-top: var(--space-xl); }
.project-card { display: flex; min-height: 15rem; flex-direction: column; padding: var(--space-xl); border: 1px solid var(--color-border); background: var(--color-surface); box-shadow: var(--shadow-sm); }
.project-card__heading { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-md); }
.project-card h3 { margin: 0; font-size: 1.35rem; }
.project-card__title { color: var(--color-text); text-decoration: none; }
.project-card__title:hover { color: var(--color-accent); }
.project-card p { color: var(--color-text-muted); }
.project-card__muted { font-style: italic; }
.project-card__link { color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.75rem; text-decoration: none; }
.project-card__link:hover { color: var(--color-accent); }
.project-card__meta { display: flex; flex-wrap: wrap; gap: var(--space-xs) var(--space-sm); margin-top: auto; font-family: var(--font-mono); font-size: 0.75rem; }
.project-card__meta span,
.project-card__meta a { padding: 0.2rem 0.45rem; border: 1px solid var(--color-border); color: var(--color-text-muted); text-decoration: none; }
.project-card__meta a:hover { border-color: var(--color-accent); color: var(--color-accent); }
.project-card__stats { display: flex; flex-wrap: wrap; gap: var(--space-lg); margin: var(--space-lg) 0 0; color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.7rem; }
.project-card__stats div { display: flex; gap: var(--space-xs); }
.project-card__stats dt { text-transform: lowercase; }
.project-card__stats dd { margin: 0; color: var(--color-text); }
.project-card__actions { margin-top: var(--space-lg); }
.project-card__actions .button { width: 100%; }
.project-detail { max-width: var(--content-max); padding-block: var(--space-4xl); }
.project-detail__header { max-width: 52rem; padding-bottom: var(--space-3xl); }
.project-detail__header h1 { margin-bottom: var(--space-md); }
.project-detail__layout { display: grid; grid-template-columns: minmax(12rem, 16rem) minmax(0, 1fr); gap: var(--space-3xl); border-top: 1px solid var(--color-border); padding-top: var(--space-3xl); }
.project-detail__metadata { align-self: start; position: sticky; top: var(--space-xl); }
.project-detail__metadata .metadata-list { margin-bottom: var(--space-xl); }
.project-detail__topics-label { margin-top: var(--space-xl); }
.project-detail__readme { min-width: 0; }
.markdown-content { max-width: 72ch; line-height: 1.75; }
.markdown-content h1, .markdown-content h2, .markdown-content h3, .markdown-content h4 { margin-top: var(--space-2xl); }
.markdown-content h1:first-child, .markdown-content h2:first-child { margin-top: 0; }
.markdown-content pre { overflow-x: auto; padding: var(--space-lg); background: var(--color-surface-muted); border: 1px solid var(--color-border); }
.markdown-content code { font-family: var(--font-mono); font-size: 0.9em; }
.markdown-content img { max-width: 100%; height: auto; }
.markdown-content blockquote { margin-inline: 0; padding-left: var(--space-lg); border-left: 3px solid var(--color-accent); color: var(--color-text-muted); }
.docs-layout { display: grid; grid-template-columns: 14rem minmax(0, 1fr) 12rem; gap: var(--space-2xl); max-width: var(--content-max); padding-block: var(--space-3xl); }
.docs-sidebar, .docs-toc { align-self: start; position: sticky; top: var(--space-xl); }
.docs-sidebar__nav, .docs-toc { display: grid; gap: var(--space-sm); }
.docs-sidebar__nav a, .docs-toc a { color: var(--color-text-muted); font-size: 0.85rem; text-decoration: none; }
.docs-sidebar__nav a:hover, .docs-sidebar__nav a.is-active, .docs-toc a:hover { color: var(--color-accent); }
.docs-sidebar__nav a.is-active { border-left: 2px solid var(--color-accent); padding-left: var(--space-sm); }
.docs-content { min-width: 0; }
.docs-content__header { padding-block: var(--space-2xl); border-bottom: 1px solid var(--color-border); }
.docs-content__header h1 { margin-bottom: 0; }
.docs-content__body { padding-block: var(--space-2xl); }
.breadcrumbs { display: flex; flex-wrap: wrap; gap: var(--space-xs); color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.75rem; }
.breadcrumbs a { color: inherit; text-decoration: none; }
.breadcrumbs a:hover, .source-link:hover { color: var(--color-accent); }
.source-link { color: var(--color-text-muted); font-family: var(--font-mono); font-size: 0.8rem; }

.error-page { max-width: var(--content-max); padding-block: var(--space-5xl); }
.error-page p:not(.eyebrow) { max-width: 50ch; color: var(--color-text-muted); }

.site-footer {
    display: flex;
    justify-content: space-between;
    gap: var(--space-xl);
    padding-block: var(--space-2xl);
    border-top: 1px solid var(--color-border);
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

.site-footer p { margin: 0; }
.site-footer__name { color: var(--color-text); font-weight: 700; }
.site-footer__links { display: flex; flex-wrap: wrap; gap: var(--space-lg); }
.site-footer__links a { text-decoration: none; }
.site-footer__links a:hover { color: var(--color-accent); }

@media (max-width: 767px) {
    .blog-layout { grid-template-columns: 1fr; gap: var(--space-xl); }
    .site-header { min-height: 4rem; }
    .site-nav__toggle { display: block; }
    .site-nav {
        position: absolute;
        z-index: 2;
        top: calc(100% + 1px);
        right: 0;
        left: 0;
        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: var(--space-sm);
        border: 1px solid var(--color-border);
        background: var(--color-surface);
        box-shadow: var(--shadow-md);
    }
    .site-nav[data-open="true"] { display: flex; }
    .site-nav__link,
    .theme-toggle { min-height: 2.75rem; padding: var(--space-sm); }
    .theme-toggle { align-self: flex-start; }
    .hero { grid-template-columns: 1fr; gap: var(--space-2xl); padding-block: var(--space-4xl); }
    .project-grid { grid-template-columns: 1fr; }
    .section-heading { align-items: flex-start; flex-direction: column; gap: var(--space-sm); }
    .project-detail__layout { grid-template-columns: 1fr; gap: var(--space-2xl); }
    .project-detail__metadata { position: static; }
    .cert-detail__layout { grid-template-columns: 1fr; gap: var(--space-2xl); }
    .cert-detail__metadata { position: static; }
    .docs-layout { grid-template-columns: 1fr; gap: var(--space-xl); }
    .docs-sidebar, .docs-toc { position: static; }
    .docs-toc { border-top: 1px solid var(--color-border); padding-top: var(--space-lg); }
    h1 { font-size: clamp(2.5rem, 14vw, 4rem); }
}

@media (max-width: 639px) {
    .site-header,
    .site-footer,
    .site-main { width: min(100% - 1.5rem, var(--container-max)); }
    .site-footer { flex-direction: column; }
    .hero__system { padding: var(--space-lg); }
    .section-block { padding-block: var(--space-3xl); }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}