/* ============================================
   heisei.boo — Swiss-Heisei Hybrid
   ============================================ */

/* --- Reset & Base --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --ivory-ground: #F5F0E8;
    --deep-umber: #3D352D;
    --warm-brown: #5A4F44;
    --faded-stone: #9B8E80;
    --dusty-rose: #C4A58A;
    --ochre-ember: #D4A054;
    --aged-indigo: #4A5568;
    --warm-charcoal: #2E2820;
    --warm-taupe: #7A6B5D;
    --pale-stone: #B8A898;

    /* Typography */
    --font-display: 'Newsreader', Georgia, serif;
    --font-body: 'Libre Franklin', 'Helvetica Neue', sans-serif;
    --font-mono: 'DM Mono', 'Courier New', monospace;

    /* Spacing (8px base unit) */
    --space-1: 8px;
    --space-2: 16px;
    --space-3: 24px;
    --space-4: 32px;
    --space-5: 40px;
    --space-6: 48px;
    --space-8: 64px;
    --space-10: 80px;
    --space-12: 96px;

    /* Spring easing */
    --spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-out: cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-weight: 400;
    font-size: clamp(0.95rem, 1.1vw, 1.1rem);
    line-height: 1.75;
    color: var(--warm-brown);
    background-color: var(--ivory-ground);
    overflow-x: hidden;
    position: relative;
}

/* --- Scroll Progress Indicator --- */
#scroll-progress {
    position: fixed;
    top: 0;
    right: 24px;
    width: 2px;
    height: 100vh;
    background: rgba(184, 168, 152, 0.2); /* #B8A898 at 20% */
    z-index: 1000;
}

#scroll-progress-fill {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 0%;
    background: var(--ochre-ember);
    transition: height 0.1s linear;
}

.scroll-label {
    position: absolute;
    right: 12px;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #B8A898;
    white-space: nowrap;
    opacity: 0.7;
    transform: translateX(100%);
    padding-right: 4px;
}

.scroll-label[data-stratum="0"] { top: 0%; }
.scroll-label[data-stratum="1"] { top: 20%; }
.scroll-label[data-stratum="2"] { top: 40%; }
.scroll-label[data-stratum="3"] { top: 60%; }
.scroll-label[data-stratum="4"] { top: 80%; }

/* --- Persistent Header --- */
#persistent-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 48px;
    display: flex;
    align-items: center;
    padding-left: 8vw;
    background: rgba(245, 240, 232, 0.9);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: 900;
    opacity: 0;
    transform: translateY(-48px);
    transition: opacity 0.4s var(--spring), transform 0.5s var(--spring);
    pointer-events: none;
    border-bottom: 1px solid rgba(122, 107, 93, 0.1);
}

#persistent-header.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.header-title {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1.1rem;
    letter-spacing: 0.12em;
    color: var(--deep-umber);
}

/* --- Geometric Background Accents --- */
#geo-accents {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
    overflow: hidden;
}

.geo-circle {
    position: absolute;
    border-radius: 50%;
    border: 1px solid var(--faded-stone);
    opacity: 0.08;
}

.geo-rect {
    position: absolute;
    border: 1px solid var(--faded-stone);
    opacity: 0.06;
}

.geo-line {
    position: absolute;
    height: 1px;
    background: var(--faded-stone);
    opacity: 0.1;
    transform-origin: left center;
}

.geo-1 { width: 200px; height: 200px; top: 15vh; left: 5vw; }
.geo-2 { width: 120px; height: 80px; top: 35vh; right: 12vw; transform: rotate(12deg); }
.geo-3 { width: 300px; top: 55vh; left: 20vw; transform: rotate(-8deg); }
.geo-4 { width: 80px; height: 80px; top: 70vh; right: 25vw; }
.geo-5 { width: 160px; height: 100px; top: 85vh; left: 8vw; transform: rotate(5deg); }
.geo-6 { width: 250px; top: 25vh; right: 30vw; transform: rotate(15deg); }
.geo-7 { width: 140px; height: 140px; bottom: 10vh; right: 8vw; }

/* --- Linen Background Texture --- */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 2px,
            rgba(155, 142, 128, 0.015) 2px,
            rgba(155, 142, 128, 0.015) 3px
        ),
        repeating-linear-gradient(
            90deg,
            transparent,
            transparent 2px,
            rgba(155, 142, 128, 0.015) 2px,
            rgba(155, 142, 128, 0.015) 3px
        );
    pointer-events: none;
    z-index: 0;
}

/* --- Strata --- */
.stratum {
    position: relative;
    min-height: 100vh;
    z-index: 2;
}

.stratum-inner {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: var(--space-12) 8vw;
}

/* --- Stratum 0: Title Plane --- */
#stratum-0 {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding-left: 8vw;
    min-height: 100vh;
}

.stratum-content {
    position: relative;
}

#hero-title {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: clamp(3.5rem, 8vw, 7rem);
    letter-spacing: -0.02em;
    color: var(--deep-umber);
    line-height: 1.05;
    opacity: 0;
    transform: translateY(24px);
}

#hero-title.animate-in {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.7s ease, transform 0.8s var(--spring);
}

#hero-rule {
    width: 0%;
    max-width: 60vw;
    height: 1px;
    background: #7A6B5D;
    margin-top: var(--space-4);
    margin-bottom: var(--space-3);
    transition: width 0.6s var(--ease-out);
}

#hero-rule.animate-in {
    width: 60vw;
}

#hero-dates {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--faded-stone);
    opacity: 0;
    transition: opacity 0.5s ease;
}

#hero-dates.animate-in {
    opacity: 1;
}

/* --- Temporal Dot Markers --- */
.temporal-dot {
    position: absolute;
    left: 8vw;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--ochre-ember);
    animation: pulse-dot 3s ease-in-out infinite;
}

.temporal-dot[data-position="bottom"] {
    bottom: 0;
}

@keyframes pulse-dot {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(212, 160, 84, 0.4);
        opacity: 1;
    }
    50% {
        box-shadow: 0 0 8px 4px rgba(212, 160, 84, 0.1);
        opacity: 0.7;
    }
}

/* --- Swiss Grid (12-column) --- */
.swiss-grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 2vw;
    width: 100%;
    align-items: start;
}

.col-2-5 {
    grid-column: 2 / 6;
}

.col-7-11 {
    grid-column: 7 / 12;
}

.col-1-5 {
    grid-column: 1 / 6;
}

/* --- Grid Lines (Swiss structural guides) --- */
.grid-lines {
    position: absolute;
    top: 0;
    left: 8vw;
    right: 8vw;
    height: 100%;
    pointer-events: none;
    z-index: 0;
}

.grid-lines::before,
.grid-lines::after {
    content: '';
    position: absolute;
    background: rgba(155, 142, 128, 0.08);
}

.grid-lines::before {
    top: 50%;
    left: 0;
    width: 100%;
    height: 1px;
    clip-path: inset(0 50% 0 50%);
    transition: clip-path 1s var(--ease-out);
}

.grid-lines::after {
    top: 0;
    left: 50%;
    width: 1px;
    height: 100%;
    clip-path: inset(50% 0 50% 0);
    transition: clip-path 1s var(--ease-out);
}

.grid-lines.visible::before {
    clip-path: inset(0 0% 0 0%);
}

.grid-lines.visible::after {
    clip-path: inset(0% 0 0% 0);
}

/* --- Stratum Labels & Titles --- */
.stratum-label {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--faded-stone);
    margin-bottom: var(--space-2);
}

.stratum-title {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: clamp(2rem, 4vw, 3.5rem);
    letter-spacing: -0.02em;
    color: var(--deep-umber);
    line-height: 1.15;
    margin-bottom: var(--space-4);
}

/* --- Text Block --- */
.text-block p {
    margin-bottom: var(--space-3);
    max-width: 540px;
}

.text-block p:last-child {
    margin-bottom: 0;
}

/* --- Glassmorphic Archive Cards --- */
.glass-card {
    border-radius: 4px;
    backdrop-filter: blur(12px) saturate(120%);
    -webkit-backdrop-filter: blur(12px) saturate(120%);
    background: rgba(245, 240, 232, 0.55);
    border: 1px solid rgba(122, 107, 93, 0.15);
    box-shadow: 0 8px 32px rgba(61, 53, 45, 0.08);
    padding: var(--space-4);
    margin-bottom: var(--space-3);
    transition: transform 0.3s var(--spring),
                box-shadow 0.3s ease,
                border-color 0.3s ease;
    position: relative;
    z-index: 3;
}

.glass-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(61, 53, 45, 0.08),
                inset 0 0 20px rgba(212, 160, 84, 0.1);
    border-color: rgba(196, 165, 138, 0.4);
}

.card-date {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--ochre-ember);
    margin-bottom: var(--space-1);
}

.card-text {
    font-family: var(--font-body);
    font-weight: 300;
    font-size: 0.95rem;
    line-height: 1.65;
    color: var(--warm-brown);
}

/* --- Stratum 2: Mirrored Grid --- */
#stratum-2 .col-1-5 {
    grid-column: 1 / 6;
}

#stratum-2 .col-7-11 {
    grid-column: 7 / 12;
}

/* --- Stratum 3: Centered Narrow Layout --- */
#stratum-3 {
    color: var(--aged-indigo);
}

#stratum-3 .stratum-title {
    color: var(--aged-indigo);
}

#stratum-3 .card-text {
    color: var(--aged-indigo);
}

.centered-grid {
    max-width: 680px;
    margin: 0 auto;
    width: 100%;
}

#stratum-3 .stratum-title {
    font-size: clamp(1.7rem, 3.4vw, 3rem);
}

#stratum-3 .text-block p {
    font-size: clamp(0.85rem, 1vw, 1rem);
}

#stratum-3 .glass-card {
    margin-bottom: var(--space-8);
}

/* --- Stratum 4: The Farewell (Dark) --- */
#stratum-4 {
    background: var(--warm-charcoal);
    color: var(--ivory-ground);
    min-height: 100vh;
    transition: background 0.6s ease;
}

#stratum-4 .stratum-inner {
    flex-direction: column;
    justify-content: center;
}

#stratum-4 .stratum-label {
    color: var(--faded-stone);
}

#stratum-4 .stratum-title {
    color: var(--ivory-ground);
}

#stratum-4 .text-block p {
    color: rgba(245, 240, 232, 0.8);
}

#stratum-4 .card-text {
    color: rgba(245, 240, 232, 0.8);
}

.glass-card-dark {
    background: rgba(46, 40, 32, 0.6);
    border: 1px solid rgba(245, 240, 232, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

.glass-card-dark:hover {
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2),
                inset 0 0 20px rgba(212, 160, 84, 0.1);
    border-color: rgba(196, 165, 138, 0.3);
}

.glass-card-dark .card-date {
    color: var(--ochre-ember);
}

#stratum-4 .centered-grid {
    max-width: 680px;
    margin: 0 auto;
}

/* --- Final Moment --- */
#final-moment {
    text-align: center;
    padding: var(--space-12) 0;
    margin-top: var(--space-12);
}

.final-text {
    font-family: var(--font-display);
    font-weight: 300;
    font-style: italic;
    font-size: 1.5rem;
    color: var(--ivory-ground);
    opacity: 0.9;
}

/* --- Reveal Animations --- */
.reveal-fade {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.7s ease, transform 0.7s var(--ease-out);
}

.reveal-fade.visible {
    opacity: 1;
    transform: translateY(0);
}

.reveal-spring {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.5s ease, transform 0.7s var(--spring);
}

.reveal-spring.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- Stratum 4 Gradient Transition Zone --- */
#stratum-3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 30vh;
    background: linear-gradient(to bottom, transparent, var(--warm-charcoal));
    pointer-events: none;
    z-index: 1;
}

/* --- Responsive --- */
@media (max-width: 900px) {
    .swiss-grid {
        display: flex;
        flex-direction: column;
        gap: var(--space-5);
    }

    .col-2-5,
    .col-7-11,
    .col-1-5 {
        grid-column: auto;
    }

    .stratum-inner {
        padding: var(--space-8) 6vw;
    }

    #stratum-0 {
        padding-left: 6vw;
    }

    #scroll-progress {
        right: 12px;
    }

    .scroll-label {
        display: none;
    }
}

@media (max-width: 600px) {
    .stratum-inner {
        padding: var(--space-6) 5vw;
    }

    #stratum-0 {
        padding-left: 5vw;
    }

    .centered-grid {
        max-width: 100%;
        padding: 0;
    }

    #persistent-header {
        padding-left: 5vw;
    }
}

/* --- State: Rest (applied to body after reaching end) --- */
body.at-rest .temporal-dot {
    animation: none;
    opacity: 0.5;
}