:root {
    --lrx-cream: #F2EDE6;
    --lrx-umber: #2C2622;
    --lrx-bark: #4A3F36;
    --lrx-charcoal: #33291F;
    --lrx-ochre: #B8763A;
    --lrx-sage: #7A8B6D;
    --lrx-sand: #D9CEBD;
    --lrx-loam: #6B5B4F;
    --lrx-sienna: #8C7E72;
    --frame: 6px;
}

*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    background: var(--lrx-cream);
    color: var(--lrx-bark);
    font-family: 'Source Serif 4', Georgia, serif;
    font-size: clamp(0.95rem, 1.2vw, 1.1rem);
    line-height: 1.7;
    letter-spacing: 0.005em;
    overflow-x: hidden;
}

/* ── Film Grain Canvas ── */
#grain-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 9999;
    opacity: 0.04;
    mix-blend-mode: multiply;
}

/* ── Index Wall Grid ── */
#index-wall {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--frame);
    padding: calc(var(--frame) * 4);
    min-height: 100vh;
    position: relative;
}

/* ── Cards ── */
.card {
    position: relative;
    overflow: hidden;
    cursor: pointer;
    border-radius: 2px;
    transition: filter 600ms ease, box-shadow 600ms ease, transform 500ms ease-out, opacity 500ms ease-out;
    opacity: 0;
    filter: blur(8px);
    transform: scale(0.96);
}

.card.revealed {
    opacity: 1;
    filter: blur(0);
    transform: scale(1);
}

.card.focused {
    filter: blur(0) brightness(1);
    box-shadow: 0 4px 24px rgba(43, 38, 34, 0.15);
    z-index: 2;
}

.card.blurred {
    filter: blur(1.5px) brightness(0.97);
}

.hero-card {
    grid-column: span 2;
    aspect-ratio: 2.39 / 1;
}

.ref-card {
    aspect-ratio: 4 / 3;
}

/* ── Duotone Background ── */
.card-duotone {
    position: absolute;
    inset: 0;
    background: var(--lrx-umber);
    mix-blend-mode: multiply;
    z-index: 1;
    opacity: 0.15;
}

/* ── Card Patterns (CSS abstract imagery) ── */
.card-pattern {
    position: absolute;
    inset: 0;
    z-index: 0;
    filter: grayscale(100%) contrast(1.1);
    opacity: 0.12;
}

.card-pattern[data-pattern="circuits"] {
    background:
        repeating-linear-gradient(0deg, transparent, transparent 18px, var(--lrx-loam) 18px, var(--lrx-loam) 19px),
        repeating-linear-gradient(90deg, transparent, transparent 24px, var(--lrx-loam) 24px, var(--lrx-loam) 25px);
}

.card-pattern[data-pattern="topo"] {
    background:
        radial-gradient(ellipse 80px 80px at 30% 40%, transparent 50%, var(--lrx-loam) 51%, transparent 52%),
        radial-gradient(ellipse 120px 60px at 70% 60%, transparent 50%, var(--lrx-loam) 51%, transparent 52%),
        radial-gradient(ellipse 60px 100px at 50% 20%, transparent 50%, var(--lrx-loam) 51%, transparent 52%);
}

.card-pattern[data-pattern="library"] {
    background: repeating-linear-gradient(
        90deg,
        var(--lrx-loam) 0px,
        var(--lrx-loam) 3px,
        transparent 3px,
        transparent 8px,
        var(--lrx-loam) 8px,
        var(--lrx-loam) 10px,
        transparent 10px,
        transparent 18px
    );
}

.card-pattern[data-pattern="astro"] {
    background:
        radial-gradient(1px 1px at 20% 30%, var(--lrx-loam), transparent),
        radial-gradient(1.5px 1.5px at 50% 70%, var(--lrx-loam), transparent),
        radial-gradient(1px 1px at 80% 20%, var(--lrx-loam), transparent),
        radial-gradient(2px 2px at 35% 85%, var(--lrx-loam), transparent),
        radial-gradient(1px 1px at 65% 45%, var(--lrx-loam), transparent),
        radial-gradient(1.5px 1.5px at 10% 60%, var(--lrx-loam), transparent),
        radial-gradient(1px 1px at 90% 90%, var(--lrx-loam), transparent),
        radial-gradient(2px 2px at 45% 15%, var(--lrx-loam), transparent);
}

/* ── Card Content ── */
.card-content {
    position: relative;
    z-index: 2;
    padding: calc(var(--frame) * 4);
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    background: linear-gradient(to top, rgba(44, 38, 34, 0.7) 0%, rgba(44, 38, 34, 0.2) 50%, transparent 100%);
}

.card-meta {
    font-family: 'DM Mono', monospace;
    font-size: clamp(0.7rem, 0.9vw, 0.8rem);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--lrx-sienna);
    margin-bottom: calc(var(--frame) * 2);
}

.card-title {
    font-family: 'Libre Baskerville', serif;
    font-weight: 700;
    font-size: clamp(1.4rem, 3vw, 2.2rem);
    line-height: 1.25;
    letter-spacing: 0.01em;
    color: var(--lrx-cream);
    margin-bottom: calc(var(--frame) * 2);
}

.hero-card .card-title {
    font-size: clamp(2rem, 5vw, 4.5rem);
}

.card-body {
    font-family: 'Source Serif 4', Georgia, serif;
    font-size: clamp(0.85rem, 1vw, 0.95rem);
    line-height: 1.6;
    color: var(--lrx-sand);
    max-width: 60ch;
}

.card-citations {
    margin-top: calc(var(--frame) * 2);
    display: flex;
    gap: calc(var(--frame) * 2);
}

.citation {
    font-family: 'DM Mono', monospace;
    font-size: clamp(0.65rem, 0.8vw, 0.75rem);
    letter-spacing: 0.06em;
    color: var(--lrx-ochre);
    text-transform: uppercase;
}

/* ── Letterbox Bars ── */
.letterbox-top,
.letterbox-bottom {
    position: absolute;
    left: 0;
    right: 0;
    height: 12px;
    background: var(--lrx-umber);
    z-index: 3;
}

.letterbox-top { top: 0; }
.letterbox-bottom { bottom: 0; }

.ref-card .letterbox-top,
.ref-card .letterbox-bottom {
    display: none;
}

/* ── Circuit Traces SVG ── */
#circuit-traces {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
    opacity: 0;
    transition: opacity 600ms ease;
}

#circuit-traces.visible {
    opacity: 1;
}

#circuit-traces line,
#circuit-traces path {
    stroke: var(--lrx-loam);
    stroke-width: 1;
    stroke-opacity: 0.2;
    stroke-dasharray: 4 8;
    fill: none;
}

#circuit-traces .trace-line.highlighted {
    stroke-opacity: 0.5;
}

#circuit-traces .solder-point {
    fill: var(--lrx-ochre);
    r: 3;
    cursor: pointer;
    pointer-events: all;
}

@keyframes pulse {
    0%, 100% { opacity: 0.6; r: 3; }
    50% { opacity: 1; r: 4; }
}

#circuit-traces .solder-point {
    animation: pulse 3s ease-in-out infinite;
}

#circuit-traces .pulse-segment {
    stroke: var(--lrx-ochre);
    stroke-opacity: 0.6;
    stroke-width: 2;
    stroke-dasharray: 12 100;
    fill: none;
    filter: url(#glow);
}

/* ── Expanded Card Overlay ── */
#expanded-overlay {
    position: fixed;
    inset: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(44, 38, 34, 0.6);
    backdrop-filter: blur(4px);
    transition: opacity 600ms cubic-bezier(0.16, 1, 0.3, 1);
    opacity: 1;
}

#expanded-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

#expanded-card {
    width: 85%;
    max-width: 1200px;
    aspect-ratio: 2.39 / 1;
    background: var(--lrx-umber);
    border: 1px solid var(--lrx-ochre);
    border-radius: 2px;
    position: relative;
    overflow: hidden;
    transform: scale(0.9);
    transition: transform 600ms cubic-bezier(0.16, 1, 0.3, 1);
}

#expanded-overlay:not(.hidden) #expanded-card {
    transform: scale(1);
}

#expanded-content {
    padding: calc(var(--frame) * 8);
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    overflow-y: auto;
}

#expanded-content .card-meta {
    color: var(--lrx-sienna);
    margin-bottom: calc(var(--frame) * 3);
}

#expanded-content .card-title {
    font-family: 'Libre Baskerville', serif;
    font-weight: 700;
    font-size: clamp(1.8rem, 4vw, 3.5rem);
    line-height: 1.25;
    letter-spacing: 0.01em;
    color: var(--lrx-cream);
    margin-bottom: calc(var(--frame) * 4);
}

#expanded-content .card-body {
    font-family: 'Source Serif 4', Georgia, serif;
    font-size: clamp(0.95rem, 1.2vw, 1.1rem);
    line-height: 1.7;
    color: var(--lrx-sand);
    max-width: 72ch;
}

#expanded-content .card-citations {
    margin-top: calc(var(--frame) * 4);
}

/* ── Colophon Footer ── */
#colophon {
    background: var(--lrx-umber);
    padding: calc(var(--frame) * 8) calc(var(--frame) * 4);
    margin-top: calc(var(--frame) * 8);
}

.colophon-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: calc(var(--frame) * 4);
    max-width: 1200px;
    margin: 0 auto;
}

.colophon-cell {
    display: flex;
    flex-direction: column;
    gap: calc(var(--frame));
}

.colophon-label {
    font-family: 'DM Mono', monospace;
    font-size: clamp(0.6rem, 0.7vw, 0.7rem);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--lrx-sienna);
}

.colophon-value {
    font-family: 'DM Mono', monospace;
    font-size: clamp(0.7rem, 0.85vw, 0.8rem);
    color: var(--lrx-sand);
    letter-spacing: 0.02em;
}

/* ── Responsive ── */
@media (max-width: 900px) {
    #index-wall {
        grid-template-columns: repeat(2, 1fr);
    }
    .hero-card {
        grid-column: span 2;
    }
    .colophon-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 540px) {
    #index-wall {
        grid-template-columns: 1fr;
    }
    .hero-card {
        grid-column: span 1;
    }
    .colophon-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}