/* Adam Bien's Workshops — index page
   web-static: no JS, no dependencies, Baseline 2025 CSS */

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: system-ui, -apple-system, sans-serif; line-height: 1.5; }

:root {
    /* Brand palette (oklch — Baseline Widely Available) */
    --color-primary: oklch(67% 0.18 49);        /* #F07102 orange */
    --color-primary-strong: oklch(60% 0.18 49);
    --color-secondary: oklch(48% 0.06 230);      /* #40697c slate */
    --color-accent: oklch(72% 0.11 230);         /* #3EB0D8 */

    --color-bg: oklch(98% 0.005 230);
    --color-surface: oklch(100% 0 0);
    --color-text: oklch(28% 0.02 250);
    --color-muted: oklch(55% 0.02 250);
    --color-border: oklch(90% 0.01 250);

    --space: clamp(1rem, 0.6rem + 1.6vw, 1.75rem);
    --radius: 14px;
    --shadow: 0 1px 2px oklch(0% 0 0 / 0.06), 0 8px 24px oklch(0% 0 0 / 0.08);
    --shadow-hover: 0 2px 4px oklch(0% 0 0 / 0.08), 0 16px 40px oklch(0% 0 0 / 0.14);

    --max-inline: 64rem;
}

@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: oklch(20% 0.02 250);
        --color-surface: oklch(25% 0.02 250);
        --color-text: oklch(93% 0.01 250);
        --color-muted: oklch(72% 0.02 250);
        --color-border: oklch(34% 0.02 250);
        --shadow: 0 1px 2px oklch(0% 0 0 / 0.3), 0 8px 24px oklch(0% 0 0 / 0.4);
        --shadow-hover: 0 2px 4px oklch(0% 0 0 / 0.4), 0 16px 40px oklch(0% 0 0 / 0.55);
    }
}

body {
    color: var(--color-text);
    background:
        radial-gradient(120% 60% at 100% 0%, oklch(67% 0.18 49 / 0.10), transparent 60%),
        var(--color-bg);
    min-block-size: 100dvh;
    padding-inline: clamp(1rem, 5vw, 3rem);
    padding-block: clamp(1.5rem, 4vw, 3rem);
}

.page {
    inline-size: 100%;
    max-inline-size: var(--max-inline);
    margin-inline: auto;
}

/* Skip link */
.skip-link {
    position: absolute;
    inset-block-start: -3rem;
    inset-inline-start: 1rem;
    background: var(--color-secondary);
    color: #fff;
    padding: 0.5rem 1rem;
    border-radius: 0 0 8px 8px;
    z-index: 10;
    transition: inset-block-start 0.2s ease;
}
.skip-link:focus-visible { inset-block-start: 0; }

/* Header */
.site-header {
    margin-block-end: clamp(2rem, 5vw, 3.5rem);
}
.site-header h1 {
    display: inline-block;
    font-size: clamp(2rem, 1.2rem + 4vw, 3.5rem);
    line-height: 1.1;
    color: #fff;
    padding: 0.4em 0.7em;
    border-radius: var(--radius);
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    box-shadow: var(--shadow);
    text-shadow: 1px 1px 2px oklch(0% 0 0 / 0.4);
}
.tagline {
    margin-block-start: 1rem;
    color: var(--color-secondary);
    font-weight: 600;
    font-size: clamp(1.1rem, 0.95rem + 0.8vw, 1.5rem);
    font-style: italic;
}

.venue-note {
    margin-block-start: 0.75rem;
    font-size: 0.9rem;
    color: var(--color-muted);
    padding-inline-start: 0.85rem;
    border-inline-start: 3px solid var(--color-accent);
}
.venue-note strong { color: var(--color-secondary); }

/* In-person CTA (airhacks.university) — shown after the virtual workshops */
.inperson-cta {
    margin-block-start: clamp(2rem, 5vw, 3rem);
    padding: clamp(1.5rem, 1rem + 2vw, 2.5rem);
    border-radius: var(--radius);
    color: #fff;
    background: linear-gradient(135deg, var(--color-secondary), var(--color-primary));
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
    contain: layout style paint;
}
.inperson-cta .inperson-badge {
    display: inline-block;
    margin-block-end: 0.85rem;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.03em;
    text-transform: uppercase;
    color: var(--color-secondary);
    background: #fff;
    padding: 0.3em 0.85em;
    border-radius: 999px;
    box-shadow: var(--shadow);
    white-space: nowrap;
}
.inperson-cta h2 {
    font-size: clamp(1.3rem, 1.1rem + 1.4vw, 2rem);
    line-height: 1.15;
    margin-block-end: 0.75rem;
}
.inperson-cta p { max-inline-size: 48ch; }
.inperson-cta strong { color: #fff; }

.inperson-link {
    display: inline-block;
    margin-block-start: 1.25rem;
    font-weight: 700;
    color: var(--color-secondary);
    background: #fff;
    text-decoration: none;
    padding: 0.7rem 1.4rem;
    border-radius: 999px;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.inperson-link:hover,
.inperson-link:focus-visible {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

/* Season groups */
.season { margin-block-end: clamp(2rem, 5vw, 3rem); }
.season > h2 {
    display: flex;
    align-items: baseline;
    gap: 0.6rem;
    font-size: clamp(1.1rem, 0.9rem + 1vw, 1.5rem);
    color: var(--color-secondary);
    margin-block-end: 1.25rem;
    padding-block-end: 0.5rem;
    border-block-end: 2px solid var(--color-border);
}
.season > h2 .new {
    font-size: 0.7rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #fff;
    background: var(--color-primary);
    padding: 0.2em 0.6em;
    border-radius: 999px;
    box-shadow: var(--shadow);
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 22rem), 1fr));
    gap: clamp(1rem, 2vw, 1.5rem);
}

/* Workshop card (anchor as block) */
.card {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    padding: clamp(1.25rem, 1rem + 1vw, 1.75rem);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-decoration: none;
    color: inherit;
    position: relative;
    overflow: hidden;
    contain: layout style paint;
    transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.card::before {
    content: "";
    position: absolute;
    inset-block: 0;
    inset-inline-start: 0;
    inline-size: 5px;
    background: linear-gradient(var(--color-primary), var(--color-accent));
}
.card:hover,
.card:focus-visible {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
    border-color: var(--color-primary);
}
.card h3 {
    font-size: clamp(1.1rem, 1rem + 0.6vw, 1.4rem);
    line-height: 1.25;
    color: var(--color-text);
}
.card .date {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    width: fit-content;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--color-primary-strong);
}
.card .arrow {
    margin-block-start: auto;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--color-secondary);
}
.card:hover .arrow,
.card:focus-visible .arrow { color: var(--color-primary); }

/* Catalog link */
.more {
    margin-block-start: clamp(1.5rem, 4vw, 2.5rem);
}
.catalog-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    color: var(--color-secondary);
    text-decoration: none;
    padding: 0.6rem 1.1rem;
    border: 1px solid var(--color-border);
    border-radius: 999px;
    background: var(--color-surface);
    transition: color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}
.catalog-link:hover,
.catalog-link:focus-visible {
    color: var(--color-primary);
    border-color: var(--color-primary);
    transform: translateY(-2px);
}

/* Registration badge (Mustache-conditional) */
.badge {
    margin-block-end: 2rem;
    padding: 1rem 1.25rem;
    border-radius: var(--radius);
    background: var(--color-secondary);
    color: #fff;
    font-weight: 600;
    box-shadow: var(--shadow);
}

/* Footer */
.site-footer {
    margin-block-start: clamp(3rem, 8vw, 5rem);
    padding-block-start: 1.5rem;
    border-block-start: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-muted);
    font-size: 0.85rem;
}

/* Focus visibility for keyboard users */
:focus-visible {
    outline: 3px solid var(--color-accent);
    outline-offset: 3px;
    border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
    }
    .card:hover,
    .card:focus-visible,
    .catalog-link:hover,
    .catalog-link:focus-visible,
    .inperson-link:hover,
    .inperson-link:focus-visible { transform: none; }
}