/* ====================================================================
   opensource.day — Neomorphic Commemorative
   Palette: Parchment #E8E0D0, Shadow warm #C8B8A0, Highlight cream #F8F0E8,
   Marble charcoal #3A3830, Classical gold #B89840, Vintage rose #C08070,
   Sage muted #808870
   Fonts: DM Serif Display (display), DM Sans (body)
   ==================================================================== */

:root {
    --parchment: #E8E0D0;
    --shadow-warm: #C8B8A0;
    --highlight-cream: #F8F0E8;
    --marble-charcoal: #3A3830;
    --classical-gold: #B89840;
    --vintage-rose: #C08070;
    --sage-muted: #808870;

    --font-display: "DM Serif Display", "Times New Roman", serif;
    --font-body: "DM Sans", system-ui, -apple-system, sans-serif;

    --column: 760px;

    /* Neomorphic shadow stacks */
    --neo-standard:
        4px 4px 12px var(--shadow-warm),
        -4px -4px 12px var(--highlight-cream);
    --neo-elevated:
        8px 8px 22px var(--shadow-warm),
        -8px -8px 22px var(--highlight-cream);
    --neo-deep:
        14px 14px 34px var(--shadow-warm),
        -14px -14px 34px var(--highlight-cream);
    --neo-inset:
        inset 5px 5px 12px var(--shadow-warm),
        inset -5px -5px 12px var(--highlight-cream);
    --neo-inset-deep:
        inset 9px 9px 18px var(--shadow-warm),
        inset -9px -9px 18px var(--highlight-cream);
    --neo-pill:
        inset 3px 3px 6px var(--shadow-warm),
        inset -3px -3px 6px var(--highlight-cream);
}

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

html {
    scroll-behavior: smooth;
}

body {
    background: var(--parchment);
    color: var(--marble-charcoal);
    font-family: var(--font-body);
    font-size: clamp(15px, 1vw, 17px);
    line-height: 1.8;
    overflow-x: hidden;
    min-height: 100vh;
}

img, svg {
    display: block;
}

/* ============== COMMEMORATIVE SEAL ============== */

.seal {
    position: relative;
    min-height: 100vh;
    width: 100%;
    display: grid;
    place-items: center;
    padding: 80px 24px;
    overflow: hidden;
}

.seal-floating-icons {
    position: absolute;
    inset: 0;
    pointer-events: none;
    color: var(--sage-muted);
}

.floating-icon {
    position: absolute;
    width: 80px;
    height: 80px;
    opacity: 0;
    transition: opacity 1400ms ease 1100ms;
    will-change: transform;
}

.seal.is-loaded .floating-icon {
    opacity: 0.18;
}

.icon-branch    { top: 12%; left: 8%;   animation: drift 14s ease-in-out infinite; }
.icon-merge     { top: 18%; right: 9%;  animation: drift 17s ease-in-out infinite reverse; }
.icon-community { bottom: 20%; left: 12%; animation: drift 19s ease-in-out infinite; }
.icon-fork      { bottom: 14%; right: 11%; animation: drift 16s ease-in-out infinite reverse; }
.icon-key       { top: 46%; left: 4%;  animation: drift 21s ease-in-out infinite; }

@keyframes drift {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50%      { transform: translate(14px, -10px) rotate(4deg); }
}

.seal-stage {
    position: relative;
    z-index: 2;
    width: min(620px, 100%);
    aspect-ratio: 1 / 1;
    display: grid;
    place-items: center;
}

.seal-medallion {
    position: relative;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: var(--parchment);
    box-shadow: 0 0 0 transparent;
    transform: scale(0.8);
    transition:
        transform 800ms cubic-bezier(.2,.8,.2,1) 200ms,
        box-shadow 800ms ease 200ms;
    display: grid;
    place-items: center;
}

.seal.is-loaded .seal-medallion {
    transform: scale(1);
    box-shadow: var(--neo-deep);
}

.seal-ornament {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    color: var(--classical-gold);
    pointer-events: none;
}

.orn-line,
.orn-laurel path,
.orn-laurel ellipse,
.orn-crest path,
.orn-crest circle,
.orn-ticks line {
    stroke-dasharray: 1400;
    stroke-dashoffset: 1400;
    transition: stroke-dashoffset 1200ms ease;
}

.seal.is-loaded .orn-line,
.seal.is-loaded .orn-laurel path,
.seal.is-loaded .orn-laurel ellipse,
.seal.is-loaded .orn-crest path,
.seal.is-loaded .orn-crest circle,
.seal.is-loaded .orn-ticks line {
    stroke-dashoffset: 0;
}

.seal-inscription {
    position: relative;
    z-index: 2;
    text-align: center;
    padding: 0 12%;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 800ms ease 700ms, transform 800ms ease 700ms;
}

.seal.is-loaded .seal-inscription {
    opacity: 1;
    transform: translateY(0);
}

.seal-eyebrow {
    display: block;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--sage-muted);
    margin-bottom: 18px;
}

.seal-domain {
    font-family: var(--font-display);
    font-weight: 400;
    font-size: clamp(36px, 5vw, 72px);
    letter-spacing: 0.02em;
    line-height: 1.05;
    color: var(--marble-charcoal);
    text-shadow:
        2px 2px 0 var(--shadow-warm),
        -1px -1px 0 var(--highlight-cream);
}

.seal-subscript {
    display: block;
    font-family: var(--font-body);
    font-style: italic;
    color: var(--sage-muted);
    font-size: clamp(13px, 1vw, 15px);
    margin-top: 10px;
    letter-spacing: 0.04em;
}

.seal-banner {
    display: inline-block;
    margin-top: 22px;
    padding: 8px 22px;
    font-family: var(--font-display);
    font-size: clamp(16px, 1.4vw, 20px);
    color: var(--classical-gold);
    letter-spacing: 0.28em;
    border-radius: 999px;
    background: var(--parchment);
    box-shadow: var(--neo-pill);
}

.seal-scroll-cue {
    position: absolute;
    bottom: 36px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    color: var(--sage-muted);
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    opacity: 0;
    transition: opacity 700ms ease 1700ms;
}

.seal.is-loaded .seal-scroll-cue { opacity: 0.85; }

.seal-scroll-cue svg {
    width: 22px;
    height: 36px;
    animation: bob 2.4s ease-in-out infinite;
}

@keyframes bob {
    0%, 100% { transform: translateY(0); }
    50%      { transform: translateY(6px); }
}

/* ============== SECTION HEADERS ============== */

.section-head {
    width: min(var(--column), 100%);
    margin: 0 auto 64px;
    text-align: center;
    padding: 0 24px;
}

.section-label {
    display: inline-block;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--classical-gold);
    margin-bottom: 18px;
    padding: 8px 22px;
    background: var(--parchment);
    border-radius: 999px;
    box-shadow: var(--neo-pill);
}

.section-title {
    font-family: var(--font-display);
    font-weight: 400;
    font-size: clamp(28px, 3.6vw, 48px);
    color: var(--marble-charcoal);
    letter-spacing: 0.01em;
    line-height: 1.2;
    margin-bottom: 18px;
    text-shadow:
        1px 1px 0 var(--shadow-warm),
        -1px -1px 0 var(--highlight-cream);
}

.section-lede {
    font-style: italic;
    color: var(--sage-muted);
    max-width: 580px;
    margin: 0 auto;
    line-height: 1.7;
}

/* ============== TIMELINE ============== */

.timeline {
    padding: 120px 24px 80px;
    background: var(--parchment);
}

.timeline-list {
    list-style: none;
    width: min(var(--column), 100%);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 64px;
    counter-reset: era;
}

.timeline-panel {
    position: relative;
    background: var(--parchment);
    border-radius: 18px;
    padding: 40px 48px;
    transition:
        transform 600ms cubic-bezier(.2,.8,.2,1),
        opacity 600ms ease,
        box-shadow 500ms ease;
    opacity: 0;
}

.panel-from-left  { transform: translateX(-30px); }
.panel-from-right { transform: translateX(30px); }

.timeline-panel.is-revealed {
    opacity: 1;
    transform: translateX(0);
}

.panel-standard { box-shadow: var(--neo-standard); }
.panel-elevated { box-shadow: var(--neo-elevated); }
.panel-deep     { box-shadow: var(--neo-deep); }

.timeline-panel.is-fully-in-view.panel-standard { box-shadow: var(--neo-elevated); }
.timeline-panel.is-fully-in-view.panel-elevated { box-shadow: var(--neo-deep); }
.timeline-panel.is-fully-in-view.panel-deep     {
    box-shadow:
        18px 18px 38px var(--shadow-warm),
        -18px -18px 38px var(--highlight-cream);
}

.timeline-panel:hover {
    transform: translateX(0) translateY(-2px);
    box-shadow:
        16px 16px 36px var(--shadow-warm),
        -16px -16px 36px var(--highlight-cream);
}

.panel-frame {
    position: absolute;
    inset: 12px;
    border: 1px solid transparent;
    border-radius: 12px;
    pointer-events: none;
    background:
        linear-gradient(135deg, transparent 0 calc(50% - 0.5px), var(--classical-gold) calc(50% - 0.5px) calc(50% + 0.5px), transparent calc(50% + 0.5px) 100%) top left/14px 14px no-repeat,
        linear-gradient(225deg, transparent 0 calc(50% - 0.5px), var(--classical-gold) calc(50% - 0.5px) calc(50% + 0.5px), transparent calc(50% + 0.5px) 100%) top right/14px 14px no-repeat,
        linear-gradient(45deg, transparent 0 calc(50% - 0.5px), var(--classical-gold) calc(50% - 0.5px) calc(50% + 0.5px), transparent calc(50% + 0.5px) 100%) bottom left/14px 14px no-repeat,
        linear-gradient(315deg, transparent 0 calc(50% - 0.5px), var(--classical-gold) calc(50% - 0.5px) calc(50% + 0.5px), transparent calc(50% + 0.5px) 100%) bottom right/14px 14px no-repeat;
    opacity: 0.4;
    transition: opacity 500ms ease;
}

.timeline-panel:hover .panel-frame { opacity: 1; }

.panel-era {
    display: inline-block;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--classical-gold);
    margin-bottom: 8px;
}

.panel-date {
    display: block;
    font-family: var(--font-display);
    font-size: clamp(20px, 2vw, 32px);
    color: var(--sage-muted);
    margin-bottom: 8px;
    letter-spacing: 0.02em;
}

.panel-title {
    font-family: var(--font-display);
    font-weight: 400;
    font-size: clamp(24px, 2.6vw, 36px);
    color: var(--marble-charcoal);
    margin-bottom: 16px;
    letter-spacing: 0.01em;
}

.panel-body {
    color: var(--marble-charcoal);
    margin-bottom: 22px;
    line-height: 1.8;
}

.panel-citations {
    list-style: none;
    border-top: 1px solid var(--shadow-warm);
    padding-top: 18px;
    display: grid;
    gap: 8px;
}

.panel-citations li {
    position: relative;
    padding-left: 20px;
    font-size: 13px;
    color: var(--sage-muted);
    font-style: italic;
}

.panel-citations li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 0.7em;
    width: 12px;
    height: 1px;
    background: var(--classical-gold);
}

/* ============== GALLERY ============== */

.gallery {
    padding: 120px 24px 80px;
    background: var(--parchment);
}

.gallery-grid {
    width: min(1080px, 100%);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 56px;
}

.gallery-piece {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 22px;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 600ms ease, transform 600ms ease;
}

.gallery-piece.is-revealed {
    opacity: 1;
    transform: translateY(0);
}

.piece-frame {
    position: relative;
    width: 220px;
    height: 220px;
    border-radius: 50%;
    background: var(--parchment);
    box-shadow: var(--neo-standard);
    display: grid;
    place-items: center;
    transition:
        box-shadow 500ms ease,
        transform 500ms ease;
}

.gallery-piece.is-revealed .piece-frame {
    transition-delay: 200ms;
    box-shadow: var(--neo-inset);
}

.gallery-piece:hover .piece-frame {
    box-shadow: var(--neo-standard);
    transform: translateY(-3px);
}

.piece-art {
    width: 64%;
    height: 64%;
    color: var(--sage-muted);
    transition: color 400ms ease, filter 400ms ease;
}

.gallery-piece:hover .piece-art {
    color: var(--vintage-rose);
    filter: drop-shadow(0 0 4px rgba(184, 152, 64, 0.35));
}

.piece-frame::before {
    content: "";
    position: absolute;
    inset: 8px;
    border-radius: 50%;
    border: 1px solid var(--classical-gold);
    opacity: 0.35;
    pointer-events: none;
    transition: opacity 400ms ease;
}

.gallery-piece:hover .piece-frame::before { opacity: 0.9; }

.gallery-piece figcaption {
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.piece-plate {
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--classical-gold);
}

.piece-title {
    font-family: var(--font-display);
    font-size: 22px;
    color: var(--marble-charcoal);
    letter-spacing: 0.01em;
}

.piece-note {
    font-style: italic;
    color: var(--sage-muted);
    font-size: 13px;
}

/* ============== CODEX ============== */

.codex {
    padding: 120px 24px 80px;
    background: var(--parchment);
}

.codex-panel {
    position: relative;
    width: min(var(--column), 100%);
    margin: 0 auto;
    background: var(--parchment);
    border-radius: 22px;
    padding: 64px 56px;
    box-shadow: var(--neo-inset-deep);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 700ms ease, transform 700ms ease;
}

.codex-panel.is-revealed {
    opacity: 1;
    transform: translateY(0);
}

.codex-frame {
    position: absolute;
    inset: 18px;
    border: 1px solid var(--classical-gold);
    border-radius: 14px;
    opacity: 0.35;
    pointer-events: none;
}

.codex-quote {
    position: relative;
    font-family: var(--font-display);
    font-size: clamp(18px, 1.6vw, 24px);
    line-height: 1.6;
    color: var(--marble-charcoal);
    text-align: center;
    margin-bottom: 16px;
    letter-spacing: 0.01em;
}

.codex-quote em {
    color: var(--vintage-rose);
    font-style: italic;
}

.codex-attribution {
    text-align: center;
    color: var(--sage-muted);
    font-style: italic;
    font-size: 13px;
    letter-spacing: 0.04em;
    margin-bottom: 32px;
}

.codex-divider {
    width: 220px;
    margin: 0 auto 32px;
    color: var(--classical-gold);
}

.codex-divider svg { width: 100%; height: 16px; }

/* ============== DEDICATION STONE ============== */

.dedication {
    padding: 80px 24px 100px;
    background: var(--parchment);
}

.dedication-stone {
    position: relative;
    width: min(880px, 100%);
    margin: 0 auto;
    background: var(--parchment);
    border-radius: 16px;
    padding: 72px 56px;
    box-shadow: var(--neo-inset-deep);
    text-align: center;
}

.dedication-border {
    position: absolute;
    inset: 18px;
    width: calc(100% - 36px);
    height: calc(100% - 36px);
    color: var(--classical-gold);
    opacity: 0.5;
    pointer-events: none;
}

.dedication-eyebrow {
    display: inline-block;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--classical-gold);
    margin-bottom: 20px;
}

.dedication-text {
    font-family: var(--font-display);
    font-size: clamp(17px, 1.4vw, 22px);
    color: var(--marble-charcoal);
    max-width: 640px;
    margin: 0 auto 36px;
    line-height: 1.7;
    letter-spacing: 0.01em;
}

.dedication-acks {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
    text-align: left;
}

.ack-block {
    padding: 18px 22px;
    background: var(--parchment);
    border-radius: 10px;
    box-shadow: var(--neo-pill);
    transition: box-shadow 400ms ease, transform 400ms ease;
}

.ack-block:hover {
    transform: translateY(-2px);
    box-shadow: var(--neo-standard);
}

.ack-label {
    display: block;
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--classical-gold);
    margin-bottom: 6px;
}

.ack-value {
    display: block;
    font-size: 13px;
    color: var(--marble-charcoal);
    line-height: 1.6;
    font-style: italic;
}

.dedication-mark {
    display: block;
    font-family: var(--font-display);
    font-size: 18px;
    letter-spacing: 0.4em;
    color: var(--vintage-rose);
}

/* ============== RESPONSIVE ============== */

@media (max-width: 720px) {
    .timeline-panel  { padding: 32px 28px; }
    .codex-panel     { padding: 48px 28px; }
    .dedication-stone{ padding: 56px 28px; }
    .panel-frame     { inset: 8px; }
    .codex-frame     { inset: 12px; }
    .seal-scroll-cue { bottom: 18px; }
}

@media (max-width: 480px) {
    .seal-stage      { width: 100%; }
    .gallery-grid    { gap: 40px; }
    .piece-frame     { width: 180px; height: 180px; }
    .dedication-acks { grid-template-columns: 1fr; }
}