/* ===== Paper Archive Room — geepity ===== */

:root {
    --bg: #fbfaf7;
    --bg-elevated: #ffffff;
    --bg-warm: #f3eee2;
    --ink: #15212e;
    --ink-soft: #3a4a5c;
    --ink-muted: #6b7785;
    --rule: #e3e0d8;
    --rule-soft: #ece9e0;
    --upstream: #1f3a52;
    --midmarket: #4a7396;
    --downstream: #7aa6cc;
    --feedback: #16a085;
    --accent: #c8392c;
    --accent-soft: rgba(200, 57, 44, 0.08);
    --gold: #b88a2c;
    --gold-light: #f5edd6;
    --shadow-soft: 0 1px 2px rgba(21, 33, 46, 0.04), 0 4px 12px rgba(21, 33, 46, 0.06);
    --shadow-hover: 0 2px 4px rgba(21, 33, 46, 0.06), 0 12px 28px rgba(21, 33, 46, 0.10);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 18px; }
body {
    font-family: 'Newsreader', Georgia, 'Times New Roman', serif;
    background: var(--bg);
    color: var(--ink);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
}

a { color: var(--ink); }
img { max-width: 100%; display: block; }

/* ===== Top nav ===== */
.nav-bar {
    position: sticky; top: 0; z-index: 100;
    background: rgba(251, 250, 247, 0.92);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--rule);
}
.nav-inner {
    max-width: 1100px; margin: 0 auto;
    padding: 1rem 1.5rem;
    display: flex; align-items: center; gap: 0.5rem;
    font-family: 'Inter', sans-serif; font-size: 0.85rem;
}
.nav-home {
    font-weight: 700; color: var(--ink); text-decoration: none;
    letter-spacing: -0.01em;
}
.nav-home:hover { color: var(--accent); }
.nav-sep { color: var(--ink-muted); }
.nav-section { color: var(--ink-soft); font-weight: 500; }

/* ===== Page wrapper ===== */
.page {
    max-width: 1100px; margin: 0 auto;
    padding: 0 1.5rem 4rem;
}

/* ===== Hero ===== */
.archive-hero {
    padding: 4.5rem 0 3rem;
    border-bottom: 1px solid var(--rule);
    margin-bottom: 3rem;
}
.archive-eyebrow {
    font-family: 'Inter', sans-serif;
    font-size: 0.72rem; font-weight: 600;
    text-transform: uppercase; letter-spacing: 0.14em;
    color: var(--accent);
    margin-bottom: 1.2rem;
}
.archive-title {
    font-family: 'Newsreader', serif;
    font-size: clamp(2.2rem, 4.5vw, 3.6rem);
    font-weight: 600; line-height: 1.05; letter-spacing: -0.015em;
    color: var(--ink);
    margin-bottom: 1.4rem;
    max-width: 880px;
}
.archive-title em {
    font-style: italic; color: var(--accent);
}
.archive-lede {
    font-size: 1.18rem;
    color: var(--ink-soft);
    line-height: 1.55;
    max-width: 720px;
    margin-bottom: 1.4rem;
}
.archive-meta {
    font-family: 'Inter', sans-serif;
    font-size: 0.82rem;
    color: var(--ink-muted);
    display: flex; align-items: center; gap: 0.6rem;
    flex-wrap: wrap;
}
.archive-count {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 500; color: var(--ink-soft);
}
.archive-meta-sep { opacity: 0.5; }

/* ===== Foundation reference (math) — distinct treatment ===== */
.archive-foundation {
    margin-bottom: 3rem;
    padding: 2rem;
    background: linear-gradient(135deg, var(--gold-light) 0%, #fbf6e6 100%);
    border: 1px solid #e6dcb6;
    border-radius: 10px;
    box-shadow: var(--shadow-soft);
    position: relative;
    overflow: hidden;
}
.archive-foundation::before {
    content: ""; position: absolute;
    top: 0; right: 0; width: 200px; height: 200px;
    background: radial-gradient(circle, rgba(184, 138, 44, 0.18), transparent 70%);
    pointer-events: none;
}
.foundation-tag {
    display: inline-block;
    font-family: 'Inter', sans-serif;
    font-size: 0.66rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.16em;
    color: var(--gold);
    background: rgba(184, 138, 44, 0.15);
    padding: 0.3rem 0.7rem;
    border-radius: 999px;
    margin-bottom: 1.2rem;
    position: relative;
}
.foundation-card {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 1.8rem;
    align-items: center;
    text-decoration: none;
    color: inherit;
    position: relative;
    z-index: 2;
}
.foundation-card:hover .foundation-card-title { color: var(--accent); }
.foundation-card-image {
    aspect-ratio: 1200 / 630;
    border-radius: 8px;
    overflow: hidden;
    background: var(--bg-elevated);
    border: 1px solid var(--rule);
}
.foundation-card-image img { width: 100%; height: 100%; object-fit: cover; }
.foundation-card-image-placeholder {
    width: 100%; height: 100%;
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, var(--upstream), var(--downstream));
    color: white; font-family: 'Newsreader', serif; font-size: 1.4rem; font-weight: 600;
}
.foundation-card-title {
    font-family: 'Newsreader', serif;
    font-size: 1.85rem; font-weight: 600;
    line-height: 1.15; letter-spacing: -0.01em;
    color: var(--ink);
    margin-bottom: 0.6rem;
    transition: color 0.2s;
}
.foundation-card-tagline {
    font-family: 'Inter', sans-serif;
    font-size: 0.72rem; font-weight: 600;
    text-transform: uppercase; letter-spacing: 0.1em;
    color: var(--gold);
    margin-bottom: 0.8rem;
}
.foundation-card-desc {
    font-family: 'Newsreader', serif;
    font-size: 1.02rem;
    color: var(--ink-soft);
    line-height: 1.5;
}
@media (max-width: 720px) {
    .foundation-card { grid-template-columns: 1fr; }
}

/* ===== Search controls ===== */
.archive-controls {
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}
.archive-search {
    width: 100%;
    font-family: 'Inter', sans-serif;
    font-size: 1rem;
    padding: 0.85rem 1.1rem;
    background: var(--bg-elevated);
    color: var(--ink);
    border: 1px solid var(--rule);
    border-radius: 8px;
    outline: none;
    transition: border-color 0.15s, box-shadow 0.15s;
}
.archive-search:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-soft);
}
.archive-results-meta {
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    color: var(--ink-muted);
    min-height: 1.2em;
}

/* ===== Paper grid ===== */
.archive-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.6rem;
}

/* ===== Paper card ===== */
.paper-card {
    background: var(--bg-elevated);
    border: 1px solid var(--rule);
    border-radius: 10px;
    overflow: hidden;
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    transition: transform 0.15s, box-shadow 0.2s, border-color 0.2s;
    box-shadow: var(--shadow-soft);
}
.paper-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
    border-color: #d4cebd;
}
.paper-card-image {
    aspect-ratio: 1200 / 630;
    background: var(--bg-warm);
    overflow: hidden;
    border-bottom: 1px solid var(--rule);
}
.paper-card-image img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.4s; }
.paper-card:hover .paper-card-image img { transform: scale(1.02); }
.paper-card-image-placeholder {
    width: 100%; height: 100%;
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, #2d4156 0%, #1f3a52 100%);
    color: rgba(255, 255, 255, 0.85);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem; letter-spacing: 0.04em;
    padding: 1rem;
    text-align: center;
}
.paper-card-body {
    padding: 1.3rem 1.4rem 1.5rem;
    display: flex; flex-direction: column;
    flex: 1;
}
.paper-card-arxiv {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.7rem;
    color: var(--accent);
    margin-bottom: 0.6rem;
    letter-spacing: 0.02em;
}
.paper-card-title {
    font-family: 'Newsreader', serif;
    font-size: 1.18rem; font-weight: 600;
    line-height: 1.2; letter-spacing: -0.005em;
    color: var(--ink);
    margin-bottom: 0.6rem;
    transition: color 0.2s;
}
.paper-card:hover .paper-card-title { color: var(--accent); }
.paper-card-authors {
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    color: var(--ink-muted);
    margin-bottom: 0.9rem;
    line-height: 1.4;
}
.paper-card-hook {
    font-family: 'Newsreader', serif;
    font-size: 0.95rem;
    line-height: 1.45;
    color: var(--ink-soft);
    flex: 1;
}
.paper-card-footer {
    margin-top: 1rem;
    padding-top: 0.8rem;
    border-top: 1px solid var(--rule-soft);
    font-family: 'Inter', sans-serif;
    font-size: 0.74rem;
    color: var(--ink-muted);
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.paper-card-cta {
    color: var(--ink-soft); font-weight: 500;
    transition: color 0.2s, transform 0.2s;
    display: inline-flex; align-items: center; gap: 0.3rem;
}
.paper-card:hover .paper-card-cta { color: var(--accent); }
.paper-card:hover .paper-card-cta-arrow { transform: translateX(3px); }
.paper-card-cta-arrow { transition: transform 0.2s; }

/* ===== Empty state ===== */
.archive-empty {
    text-align: center;
    font-family: 'Newsreader', serif;
    font-size: 1.05rem;
    color: var(--ink-muted);
    padding: 3rem 1rem;
    font-style: italic;
}

/* ===== Footer ===== */
.archive-footer {
    max-width: 1100px;
    margin: 0 auto;
    padding: 2.5rem 1.5rem 3rem;
    font-family: 'Inter', sans-serif;
    font-size: 0.82rem;
    color: var(--ink-muted);
    border-top: 1px solid var(--rule);
}
.archive-footer a { color: var(--ink-soft); text-decoration: none; }
.archive-footer a:hover { color: var(--accent); }

/* ===== Responsive ===== */
@media (max-width: 600px) {
    .page { padding: 0 1rem 3rem; }
    .archive-hero { padding: 2.5rem 0 2rem; }
    .archive-foundation { padding: 1.4rem; }
    .foundation-card-title { font-size: 1.4rem; }
}