/* ==========================================================================
   daitoua.com — 大東亜 Archive
   Swiss-rationalist bones, pastoral-romantic skin.
   Midnight-blue dominant palette; broken-grid layout; micro-interactions.
   Typography annotations: IBM Plex Mono 13px/20px. This mathematical
   consistency is the Swiss-rationalist backbone that keeps the broken-grid
   displacement from feeling chaotic. IBM Plex Mono" (Google Fonts; IBM Plex
   Sans body: 17px/28.8px; IBM Plex Sans" (Google Fonts. Interaction
   System System: System:: System:* System:** IntersectionObserver` for wave-form activation — only animate
   waves that are within or near the viewport (rootMargin: 200px. Interstitial
   Waves Waves: Waves:: Waves:* Waves:** Between archive segments.
   ========================================================================== */

:root {
    /* Palette */
    --deep-ocean: #0a1628;
    --slate-water: #2d3a4f;
    --horizon-line: #3a4a6b;
    --body-text: #c8d0dc;
    --lantern-gold: #d4a55a;
    --wave-foam: #7b9bb8;
    --paper-ash: #e8e4df;
    --charcoal-ink: #1a1e26;
    --hair-line: #6a7b9e;

    /* Type */
    --display: "Bebas Neue", "Inter", "Space Grotesk", sans-serif;
    --body: "IBM Plex Sans", "Inter", system-ui, sans-serif;
    --mono: "IBM Plex Mono", ui-monospace, "Menlo", monospace;
    --jp: "Noto Serif JP", "IBM Plex Sans", serif;

    /* Rhythm — baseline 8px */
    --s1: 8px;
    --s2: 16px;
    --s3: 24px;
    --s4: 32px;
    --s5: 48px;
    --s6: 64px;
    --s7: 96px;
    --s8: 128px;
    --s9: 192px;
}

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

html {
    background: var(--deep-ocean);
    color: var(--body-text);
    font-family: var(--body);
    font-weight: 300;
    font-size: 17px;
    line-height: 1.8;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

body {
    background: var(--deep-ocean);
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

/* Subtle fog grain across the whole page */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    background:
        radial-gradient(ellipse at 50% 50%, transparent 40%, rgba(10, 22, 40, 0.55) 100%),
        radial-gradient(ellipse at 20% 80%, rgba(123, 155, 184, 0.04), transparent 40%);
    mix-blend-mode: multiply;
}

/* ==========================================================================
   Scroll rail
   ========================================================================== */
.scroll-rail {
    position: fixed;
    top: 0;
    right: 24px;
    height: 100vh;
    width: 60px;
    z-index: 20;
    pointer-events: none;
}

.scroll-rail-line {
    position: absolute;
    right: 24px;
    top: 10vh;
    bottom: 10vh;
    width: 2px;
    background: var(--horizon-line);
    opacity: 0.55;
}

.scroll-progress {
    position: absolute;
    right: 22px;
    top: 10vh;
    width: 6px;
    height: 0;
    background: linear-gradient(180deg, transparent 0%, var(--wave-foam) 40%, var(--wave-foam) 100%);
    opacity: 0.85;
    pointer-events: none;
    transition: height 0.06s linear;
}

.notch {
    position: absolute;
    right: 18px;
    width: 14px;
    height: 14px;
    padding: 0;
    border: none;
    background: transparent;
    cursor: pointer;
    pointer-events: auto;
    transform: translateY(-50%);
}

.notch::before {
    content: "";
    position: absolute;
    right: 4px;
    top: 50%;
    width: 10px;
    height: 1px;
    background: var(--horizon-line);
    transform: translateY(-50%);
    transition: background 0.3s, width 0.3s;
}

.notch.active::before,
.notch:hover::before {
    background: var(--lantern-gold);
    width: 16px;
    right: 0;
}

.notch::after {
    content: "";
    position: absolute;
    right: 9px;
    top: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--lantern-gold);
    transform: translate(50%, -50%);
    opacity: 0;
    pointer-events: none;
}

.notch.pulse::after {
    animation: notch-pulse 600ms ease-out forwards;
}

@keyframes notch-pulse {
    0%   { width: 6px;  height: 6px;  opacity: 0.9; }
    100% { width: 12px; height: 12px; opacity: 0; }
}

.notch-label {
    position: absolute;
    right: 26px;
    top: 50%;
    transform: translateY(-50%);
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.12em;
    color: var(--hair-line);
    opacity: 0;
    transition: opacity 0.3s, color 0.3s;
    white-space: nowrap;
    pointer-events: none;
}

.notch:hover .notch-label,
.notch.active .notch-label {
    opacity: 1;
    color: var(--lantern-gold);
}

/* ==========================================================================
   Threshold / Hero
   ========================================================================== */
.threshold {
    position: relative;
    min-height: 100vh;
    width: 100%;
    display: flex;
    align-items: flex-end;
    justify-content: flex-start;
    padding: var(--s7) var(--s6) var(--s8);
    overflow: hidden;
    background: var(--deep-ocean);
}

.threshold-figure {
    position: absolute;
    inset: 0;
    z-index: 0;
    overflow: hidden;
}

.threshold-image {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 30% 40%, rgba(123, 155, 184, 0.35) 0%, transparent 55%),
        radial-gradient(ellipse at 75% 25%, rgba(58, 74, 107, 0.55) 0%, transparent 60%),
        linear-gradient(180deg,
            #0a1628 0%,
            #132238 25%,
            #1d2f4a 45%,
            #2d3a4f 60%,
            #3a4a6b 68%,
            #1d2f4a 72%,
            #0a1628 100%);
    mix-blend-mode: luminosity;
    filter: contrast(1.1) brightness(0.9);
}

/* horizon suggestion */
.threshold-image::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 66%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(123, 155, 184, 0.55), transparent);
    box-shadow: 0 0 24px rgba(123, 155, 184, 0.2);
}

/* thin wave-form ripple suggestion */
.threshold-image::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 78%;
    height: 180px;
    background:
        repeating-linear-gradient(
            180deg,
            transparent 0px,
            transparent 18px,
            rgba(123, 155, 184, 0.035) 18px,
            rgba(123, 155, 184, 0.035) 19px
        );
    mask-image: linear-gradient(180deg, transparent, black 30%, black 70%, transparent);
    -webkit-mask-image: linear-gradient(180deg, transparent, black 30%, black 70%, transparent);
}

.threshold-content {
    position: relative;
    z-index: 2;
    max-width: 52em;
    margin-bottom: 30vh;
}

.threshold-meta {
    font-family: var(--mono);
    font-weight: 300;
    font-size: 13px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--hair-line);
    margin-bottom: var(--s3);
}

.threshold-title {
    font-family: var(--display);
    font-weight: 400;
    font-size: clamp(2.5rem, 6.5vw, 5.5rem);
    line-height: 1.02;
    letter-spacing: 0.02em;
    color: var(--body-text);
    margin-bottom: var(--s4);
}

.threshold-caption {
    max-width: 38em;
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--body-text);
    opacity: 0.85;
}

.threshold-descent {
    position: absolute;
    left: 50%;
    bottom: var(--s5);
    transform: translateX(-50%);
    z-index: 3;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--s2);
}

.descent-line {
    display: block;
    width: 1px;
    height: 64px;
    background: linear-gradient(180deg, transparent, var(--wave-foam));
    opacity: 0.6;
    animation: descent-slide 2.6s ease-in-out infinite;
}

@keyframes descent-slide {
    0%   { transform: translateY(-10px); opacity: 0; }
    40%  { opacity: 0.6; }
    100% { transform: translateY(14px); opacity: 0; }
}

.descent-label {
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--hair-line);
}

/* ==========================================================================
   Archive / Era
   ========================================================================== */
.archive {
    position: relative;
    z-index: 2;
    padding: 0;
}

.era {
    position: relative;
    padding: var(--s9) var(--s6) var(--s8);
    contain: layout style paint;
    background: var(--deep-ocean);
    overflow: visible;
}

/* radial fog overlay per era */
.era::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(ellipse at 50% 40%, transparent 20%, rgba(10, 22, 40, 0.5) 90%);
    z-index: 1;
}

.era-grid {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    grid-auto-rows: min-content;
    gap: var(--s4) var(--s3);
    max-width: 1440px;
    margin: 0 auto;
}

/* ---- Odd eras: shift content left ---- */
.era-odd .era-header       { grid-column: 1 / span 5;  grid-row: 1; }
.era-odd .era-photo-lead   { grid-column: 6 / span 7;  grid-row: 1 / span 2; margin-top: var(--s4); }
.era-odd .era-body         { grid-column: 1 / span 6;  grid-row: 2; padding-top: var(--s5); }
.era-odd .era-margin       { grid-column: 8 / span 4;  grid-row: 3; padding-top: var(--s2); }
.era-odd .era-photo-detail { grid-column: 2 / span 5;  grid-row: 3; }

/* ---- Even eras: shift content right ---- */
.era-even .era-header       { grid-column: 4 / span 6;  grid-row: 1; text-align: right; }
.era-even .era-photo-lead   { grid-column: 1 / span 6;  grid-row: 2; }
.era-even .era-body         { grid-column: 6 / span 7;  grid-row: 2; padding-top: var(--s5); }
.era-even .era-margin       { grid-column: 1 / span 4;  grid-row: 3; padding-top: var(--s2); }
.era-even .era-photo-detail { grid-column: 6 / span 6;  grid-row: 3; }

/* ---- Era header ---- */
.era-header {
    position: relative;
}

.era-kanji {
    display: block;
    font-family: var(--jp);
    font-weight: 200;
    font-size: clamp(2rem, 4vw, 3rem);
    color: var(--horizon-line);
    opacity: 0.7;
    letter-spacing: 0.15em;
    margin-bottom: var(--s2);
}

.era-label {
    font-family: var(--display);
    font-weight: 400;
    font-size: clamp(3rem, 8vw, 7rem);
    line-height: 1;
    letter-spacing: 0.08em;
    color: var(--body-text);
    margin-bottom: var(--s4);
    will-change: transform;
}

.era-dash {
    display: inline-block;
    color: var(--lantern-gold);
    padding: 0 0.15em;
    font-weight: 400;
}

.era-subtitle {
    font-family: var(--mono);
    font-weight: 300;
    font-size: 13px;
    line-height: 1.5;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--hair-line);
    max-width: 28em;
}

.era-even .era-subtitle {
    margin-left: auto;
}

/* ---- Era body text ---- */
.era-body {
    max-width: 38em;
}

.lede {
    font-size: 1.25rem;
    line-height: 1.65;
    font-weight: 400;
    color: var(--body-text);
    margin-bottom: var(--s3);
}

.era-body p {
    font-size: 1.0625rem;
    line-height: 1.8;
    font-weight: 300;
    color: var(--body-text);
    margin-bottom: var(--s3);
}

.era-body em {
    font-style: italic;
    color: var(--wave-foam);
}

/* ---- Blockquote ---- */
.era-quote {
    position: relative;
    margin: var(--s5) 0 var(--s4);
    padding: var(--s4) var(--s5);
    border-left: 1px solid var(--horizon-line);
    background: linear-gradient(180deg, rgba(45, 58, 79, 0.35), rgba(45, 58, 79, 0.1));
}

.quote-mark {
    font-family: var(--jp);
    font-weight: 300;
    font-size: 2.5rem;
    color: var(--horizon-line);
    line-height: 1;
    position: absolute;
    top: 8px;
    left: 8px;
}

.quote-mark.quote-close {
    top: auto;
    left: auto;
    bottom: 4px;
    right: 8px;
}

.quote-jp {
    font-family: var(--jp);
    font-weight: 300;
    font-size: 1.25rem;
    line-height: 1.9;
    color: var(--body-text);
    margin-bottom: var(--s2) !important;
    letter-spacing: 0.05em;
}

.quote-en {
    font-family: var(--body);
    font-weight: 300;
    font-style: italic;
    font-size: 1rem;
    line-height: 1.7;
    color: var(--wave-foam);
    margin-bottom: var(--s2) !important;
}

.era-quote cite {
    display: block;
    font-family: var(--mono);
    font-style: normal;
    font-size: 0.8125rem;
    line-height: 1.5;
    color: var(--hair-line);
    letter-spacing: 0.04em;
    margin-top: var(--s2);
}

.cite-source {
    color: var(--wave-foam);
}

/* ---- Margin / metadata ---- */
.era-margin {
    padding-left: var(--s2);
    border-left: 1px solid rgba(58, 74, 107, 0.4);
}

.meta-list {
    font-family: var(--mono);
    font-size: 0.8125rem;
    line-height: 1.5;
    color: var(--hair-line);
    display: grid;
    grid-template-columns: auto 1fr;
    column-gap: var(--s2);
    row-gap: 4px;
}

.meta-list dt {
    color: var(--horizon-line);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 10px;
    padding-top: 6px;
}

.meta-list dd {
    color: var(--body-text);
    opacity: 0.9;
    padding-bottom: var(--s1);
    border-bottom: 1px solid rgba(58, 74, 107, 0.2);
}

/* ---- Figures / duotone photo surfaces ---- */
.era-photo {
    position: relative;
    overflow: hidden;
    background: var(--slate-water);
}

.era-photo figcaption {
    display: flex;
    flex-direction: column;
    gap: 4px;
    padding: var(--s2) 0;
    font-family: var(--mono);
    font-size: 0.8125rem;
    line-height: 1.5;
    color: var(--hair-line);
}

.cap-code {
    letter-spacing: 0.2em;
    color: var(--lantern-gold);
    font-size: 10px;
    text-transform: uppercase;
}

.cap-text {
    color: var(--body-text);
    font-family: var(--body);
    font-size: 0.875rem;
    font-weight: 300;
    font-style: italic;
    opacity: 0.9;
}

/* simulated duotone images with CSS art */
.photo-surface {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 10;
    filter: url(#duotone);
    transition: filter 0.4s ease;
    overflow: hidden;
    background: var(--slate-water);
    isolation: isolate;
}

.era-photo-lead .photo-surface   { aspect-ratio: 16 / 11; }
.era-photo-detail .photo-surface { aspect-ratio: 4 / 3;   }

.photo-surface::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, #6a7b9e 0%, #2d3a4f 60%, #0a1628 100%);
}

.photo-surface::after {
    content: "";
    position: absolute;
    inset: 0;
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    mix-blend-mode: screen;
    opacity: 0.85;
}

/* Unique image look per photo slot */
.photo-surface[data-photo="battleship"]::after {
    background:
        linear-gradient(180deg, transparent 0%, transparent 50%, rgba(0,0,0,0.45) 62%, transparent 78%),
        radial-gradient(ellipse 50% 22% at 50% 56%, rgba(10, 22, 40, 0.9) 0%, rgba(10, 22, 40, 0.5) 55%, transparent 75%),
        linear-gradient(180deg, #8fa7c0 0%, #4a5f7d 45%, #1d2f4a 70%, #0a1628 100%);
}
.photo-surface[data-photo="battleship"]::before {
    background:
        radial-gradient(ellipse 10% 20% at 42% 50%, #0a1628 0%, transparent 70%),
        radial-gradient(ellipse 6% 14% at 56% 52%, #0a1628 0%, transparent 70%),
        linear-gradient(180deg, #8fa7c0 0%, #4a5f7d 58%, #1d2f4a 72%, #0a1628 100%);
}

.photo-surface[data-photo="portsmouth"]::after {
    background:
        radial-gradient(circle at 30% 45%, rgba(10,22,40,0.8) 0%, transparent 40%),
        radial-gradient(circle at 70% 55%, rgba(10,22,40,0.75) 0%, transparent 40%),
        linear-gradient(180deg, #2d3a4f 0%, #1a2435 50%, #0a1628 100%);
}

.photo-surface[data-photo="seoul"]::after {
    background:
        linear-gradient(0deg, transparent 0%, transparent 55%, rgba(10,22,40,0.55) 80%, transparent 100%),
        repeating-linear-gradient(90deg, transparent 0px, transparent 24px, rgba(10,22,40,0.25) 24px, rgba(10,22,40,0.25) 25px),
        linear-gradient(180deg, #8fa7c0 0%, #5a6f8c 45%, #2d3a4f 70%, #1a2435 100%);
}

.photo-surface[data-photo="tsingtao"]::after {
    background:
        radial-gradient(ellipse 40% 20% at 50% 70%, rgba(123,155,184,0.3), transparent),
        linear-gradient(180deg, #3a4a6b 0%, #2d3a4f 40%, #0a1628 100%),
        repeating-linear-gradient(45deg, transparent 0 40px, rgba(10,22,40,0.15) 40px 41px);
}

.photo-surface[data-photo="tokyo-ruin"]::after {
    background:
        linear-gradient(180deg, rgba(10,22,40,0.2), rgba(10,22,40,0.8)),
        repeating-linear-gradient(90deg, transparent 0 12px, rgba(10,22,40,0.3) 12px 13px),
        repeating-linear-gradient(0deg, transparent 0 24px, rgba(10,22,40,0.2) 24px 25px),
        linear-gradient(180deg, #6a7b9e 0%, #3a4a6b 50%, #1a2435 100%);
}

.photo-surface[data-photo="ginza"]::after {
    background:
        radial-gradient(circle at 20% 70%, rgba(212,165,90,0.12), transparent 20%),
        radial-gradient(circle at 55% 60%, rgba(212,165,90,0.1), transparent 18%),
        radial-gradient(circle at 80% 65%, rgba(212,165,90,0.12), transparent 20%),
        linear-gradient(180deg, #1a2435 0%, #0a1628 100%);
}

.photo-surface[data-photo="mukden"]::after {
    background:
        radial-gradient(ellipse 30% 10% at 50% 40%, rgba(212,165,90,0.18), transparent 70%),
        linear-gradient(180deg, #3a4a6b 0%, #1a2435 55%, #0a1628 100%),
        repeating-linear-gradient(30deg, transparent 0 60px, rgba(10,22,40,0.18) 60px 61px);
}

.photo-surface[data-photo="shanghai"]::after {
    background:
        linear-gradient(180deg, rgba(58,74,107,0.25), rgba(10,22,40,0.9)),
        repeating-linear-gradient(95deg, transparent 0 18px, rgba(10,22,40,0.2) 18px 19px),
        linear-gradient(180deg, #5a6f8c 0%, #2d3a4f 60%, #0a1628 100%);
}

.photo-surface[data-photo="pearl"]::after {
    background:
        radial-gradient(circle at 55% 45%, rgba(212,165,90,0.22), transparent 25%),
        radial-gradient(circle at 55% 45%, rgba(10,22,40,0.5), transparent 40%),
        linear-gradient(180deg, #6a7b9e 0%, #3a4a6b 55%, #0a1628 100%);
}

.photo-surface[data-photo="missouri"]::after {
    background:
        linear-gradient(180deg, rgba(10,22,40,0.4), rgba(10,22,40,0.8)),
        repeating-linear-gradient(180deg, transparent 0 60px, rgba(123,155,184,0.08) 60px 61px),
        linear-gradient(180deg, #2d3a4f 0%, #1a2435 50%, #0a1628 100%);
}

/* hover luminance shift on figures */
.era-photo:hover .photo-surface {
    filter: url(#duotone-warm);
}

/* ---- Displacement diagonal line between sections ---- */
.displacement-line {
    display: block;
    width: 100%;
    height: 40px;
    margin-top: var(--s5);
    opacity: 0.5;
}

/* ==========================================================================
   Interstitial waves
   ========================================================================== */
.interstitial {
    position: relative;
    width: 100%;
    height: 220px;
    background: var(--deep-ocean);
    overflow: hidden;
    padding: 0;
}

.wave-svg {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
}

.wave-svg path {
    fill: none;
    stroke: var(--wave-foam);
    stroke-width: 1.2;
    stroke-opacity: 0;
    will-change: d;
    transition: stroke-opacity 300ms ease;
}

.interstitial.in-view .wave-svg path {
    stroke-opacity: 0.4;
}

.interstitial-label {
    position: absolute;
    right: var(--s6);
    bottom: var(--s3);
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--hair-line);
    opacity: 0.65;
}

/* ==========================================================================
   Reflection pool / footer
   ========================================================================== */
.reflection-pool {
    position: relative;
    background: var(--paper-ash);
    color: var(--charcoal-ink);
    padding: var(--s9) var(--s6) var(--s7);
    margin-top: 0;
    z-index: 3;
}

.reflection-grid {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: var(--s5) var(--s4);
    align-items: start;
}

.reflection-kanji {
    grid-column: 1 / span 3;
    font-family: var(--jp);
    font-weight: 200;
    font-size: clamp(5rem, 12vw, 9rem);
    line-height: 1;
    color: var(--charcoal-ink);
    letter-spacing: 0;
    opacity: 0.9;
}

.reflection-body {
    grid-column: 4 / span 7;
}

.reflection-lede {
    font-family: var(--display);
    font-size: clamp(1.75rem, 3vw, 2.75rem);
    line-height: 1.1;
    letter-spacing: 0.06em;
    color: var(--charcoal-ink);
    margin-bottom: var(--s4);
}

.reflection-body p {
    font-size: 1.0625rem;
    line-height: 1.85;
    font-weight: 300;
    color: var(--charcoal-ink);
    margin-bottom: var(--s3);
    max-width: 36em;
}

.reflection-jp {
    font-family: var(--jp);
    font-weight: 300;
    font-size: 1.25rem;
    color: var(--charcoal-ink);
    margin-top: var(--s4);
    margin-bottom: var(--s1) !important;
    letter-spacing: 0.08em;
}

.reflection-jp-en {
    font-family: var(--body);
    font-style: italic;
    font-size: 1rem !important;
    color: var(--horizon-line) !important;
    opacity: 0.85;
}

.bibliography {
    grid-column: 4 / span 8;
    margin-top: var(--s5);
    padding-top: var(--s4);
    border-top: 1px solid rgba(26, 30, 38, 0.2);
}

.bibliography h3 {
    font-family: var(--mono);
    font-weight: 400;
    font-size: 12px;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--charcoal-ink);
    margin-bottom: var(--s3);
}

.bibliography ol {
    list-style: none;
    counter-reset: bib;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--s2) var(--s4);
}

.bibliography li {
    counter-increment: bib;
    position: relative;
    padding-left: var(--s4);
    font-size: 0.9375rem;
    line-height: 1.6;
    font-weight: 300;
    color: var(--charcoal-ink);
}

.bibliography li::before {
    content: counter(bib, decimal-leading-zero);
    position: absolute;
    left: 0;
    top: 2px;
    font-family: var(--mono);
    font-size: 11px;
    color: var(--horizon-line);
    letter-spacing: 0.15em;
}

.bibliography em {
    font-style: italic;
}

.bib-mono {
    font-family: var(--mono);
    font-weight: 400;
    font-size: 0.875rem;
    letter-spacing: 0.12em;
    color: var(--horizon-line);
}

.final-wave {
    grid-column: 1 / -1;
    width: 100%;
    height: 80px;
    margin-top: var(--s5);
}

.final-wave path {
    fill: none;
    stroke: var(--charcoal-ink);
    stroke-width: 1;
    stroke-opacity: 0.55;
}

.colophon {
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    gap: 4px;
    font-family: var(--mono);
    font-size: 0.75rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--horizon-line);
    margin-top: var(--s3);
    padding-top: var(--s3);
    border-top: 1px solid rgba(26, 30, 38, 0.15);
}

.colophon-line:first-child {
    color: var(--charcoal-ink);
}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 960px) {
    .threshold {
        padding: var(--s6) var(--s4) var(--s7);
    }

    .era {
        padding: var(--s7) var(--s4) var(--s6);
    }

    .era-grid,
    .era-odd .era-grid,
    .era-even .era-grid {
        grid-template-columns: repeat(6, 1fr);
    }

    .era-odd .era-header,
    .era-even .era-header       { grid-column: 1 / -1; grid-row: auto; text-align: left; }
    .era-odd .era-photo-lead,
    .era-even .era-photo-lead   { grid-column: 1 / -1; grid-row: auto; margin-top: 0; }
    .era-odd .era-body,
    .era-even .era-body         { grid-column: 1 / -1; grid-row: auto; padding-top: var(--s3); }
    .era-odd .era-margin,
    .era-even .era-margin       { grid-column: 1 / -1; grid-row: auto; padding-top: var(--s3); }
    .era-odd .era-photo-detail,
    .era-even .era-photo-detail { grid-column: 1 / -1; grid-row: auto; }

    .era-even .era-subtitle { margin-left: 0; }

    .reflection-pool {
        padding: var(--s7) var(--s4) var(--s6);
    }
    .reflection-grid {
        grid-template-columns: repeat(6, 1fr);
    }
    .reflection-kanji { grid-column: 1 / -1; }
    .reflection-body  { grid-column: 1 / -1; }
    .bibliography     { grid-column: 1 / -1; }
    .bibliography ol  { grid-template-columns: 1fr; }

    .scroll-rail {
        right: 8px;
        width: 44px;
    }
    .notch-label { display: none; }
}

@media (max-width: 560px) {
    html { font-size: 16px; }
    .threshold-title { font-size: clamp(2rem, 9vw, 3rem); }
    .era-label { font-size: clamp(2.5rem, 14vw, 4rem); }
    .scroll-rail { display: none; }
}

@media (prefers-reduced-motion: reduce) {
    .descent-line { animation: none; }
    .wave-svg path { animation: none !important; }
}