/* =====================================================
   heisei.day  --  kakejiku scroll for the Heisei era
   palette: #5d6b54 #e8dcc4 #fdf8ee #2c3a4a #a83232
            #d4b896 #3a342e #f4ede0 + #8b6f47 #7a6852
   ===================================================== */

:root {
    --kinari:     #f4ede0;   /* unbleached washi paper */
    --kinari-2:   #e8dcc4;   /* aged paper deeper */
    --reiwa-bg:   #fdf8ee;   /* lighter wash for epilogue */
    --sumi:       #3a342e;   /* sumi ink near-black */
    --kuwacha:    #8b6f47;   /* mulberry tea, hairlines */
    --kuwacha-2:  #7a6852;   /* aged photo brown */
    --shu:        #a83232;   /* vermilion ceremonial */
    --moegi:      #5d6b54;   /* young-grass green */
    --kachi:      #2c3a4a;   /* deep indigo navy */
    --hikari:     #d4b896;   /* highlight cream */

    --ease-ink:   cubic-bezier(0.16, 0.84, 0.32, 1);

    --rail-w:     38vw;
    --rail-x:     8vw;

    --display-font: "Shippori Mincho", "Noto Serif JP", serif;
    --body-font:    "Cormorant Garamond", "Shippori Mincho", serif;
    --hand-font:    "Klee One", "Cormorant Garamond", cursive;
    --num-font:     "Noto Serif JP", serif;
    --latin-num:    "Inter", "Cormorant Garamond", sans-serif;
}

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

html {
    scroll-behavior: smooth;
    background: var(--kinari);
}

body {
    background: var(--kinari);
    color: var(--sumi);
    font-family: var(--body-font);
    font-size: 1.0625rem;
    line-height: 1.85;
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
    letter-spacing: 0.005em;

    /* aged-paper deeper band on the right */
    background-image: linear-gradient(
        to right,
        var(--kinari) 0%,
        var(--kinari) 46%,
        var(--kinari-2) 100%
    );
}

/* ---------------- ambient andon lamp ---------------- */
.andon-light {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    /* andon lamp: #f4ede0 -> #ebe0c8 warm radial */
    background: radial-gradient(
        circle at 28vw var(--lamp-y, 30vh),
        rgba(244, 237, 224, 0.0) 0%,
        rgba(235, 224, 200, 0.22) 28%,
        #ebe0c800 60%
    );
    transition: background 800ms var(--ease-ink);
    will-change: background;
}

/* ---------------- grain overlay ---------------- */
.grain-overlay {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 2;
    opacity: 0.55;
    mix-blend-mode: multiply;
}

/* ---------------- timeline spine ---------------- */
.timeline-spine {
    position: fixed;
    top: 0;
    left: calc(var(--rail-x) - 2.4vw);
    width: 1px;
    height: 100vh;
    z-index: 3;
    pointer-events: none;
}
.spine-line {
    position: absolute;
    top: 4vh;
    left: 0;
    width: 1px;
    height: var(--spine-h, 0vh);
    background: linear-gradient(
        to bottom,
        rgba(139, 111, 71, 0)  0%,
        rgba(139, 111, 71, 0.55) 8%,
        rgba(139, 111, 71, 0.55) 92%,
        rgba(139, 111, 71, 0) 100%
    );
    transition: height 600ms var(--ease-ink);
}

/* ---------------- panels ---------------- */
.panel,
.interlude {
    position: relative;
    width: 100%;
    min-height: 110vh;
    padding: 18vh 0 14vh 0;
    overflow: hidden;
    z-index: 4;
}
.panel--prologue { min-height: 100vh; padding-top: 14vh; }
.panel--epilogue {
    min-height: 100vh;
    background: linear-gradient(to bottom, var(--kinari) 0%, var(--reiwa-bg) 70%);
}

.panel--solemn {
    background: linear-gradient(
        to bottom,
        var(--kinari) 0%,
        rgba(44, 58, 74, 0.045) 50%,
        var(--kinari) 100%
    );
}

/* ---------------- content rail ---------------- */
.content-rail {
    position: relative;
    width: var(--rail-w);
    margin-left: var(--rail-x);
    z-index: 6;
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 1200ms var(--ease-ink), transform 1200ms var(--ease-ink);
}

.panel.is-visible .content-rail,
.interlude.is-visible .content-rail,
.interlude.is-visible .interlude-line {
    opacity: 1;
    transform: translateY(0);
}

.content-rail.align-left   { text-align: left; }
.content-rail.align-right  { text-align: right; margin-left: calc(var(--rail-x) + 8vw); width: calc(var(--rail-w) - 4vw); }
.content-rail.align-center { text-align: center; margin-left: auto; margin-right: auto; width: min(60vw, 720px); }
.content-rail.indent       { padding-left: 4vw; }

@media (max-width: 880px) {
    :root { --rail-w: 80vw; --rail-x: 8vw; }
    .content-rail.align-right { margin-left: var(--rail-x); width: var(--rail-w); text-align: left; }
}

/* ---------------- prologue ---------------- */
.site-title {
    font-family: var(--display-font);
    font-weight: 500;
    margin-bottom: 4vh;
}
.title-svg {
    width: 100%;
    max-width: 560px;
    height: auto;
    overflow: visible;
}
.title-stroke {
    fill: var(--sumi);
    stroke: var(--sumi);
    stroke-width: 0.6;
    stroke-dasharray: 1200;
    stroke-dashoffset: 1200;
    fill-opacity: 0;
    transition: fill-opacity 1400ms var(--ease-ink);
}
.title-stroke--latin {
    fill: var(--kuwacha);
    stroke: var(--kuwacha);
}

.site-title.drawn .title-stroke {
    animation: titleInk 2400ms var(--ease-ink) forwards;
}
.site-title.drawn .title-stroke--latin {
    animation-delay: 700ms;
}

@keyframes titleInk {
    0%   { stroke-dashoffset: 1200; fill-opacity: 0; }
    60%  { stroke-dashoffset: 0;    fill-opacity: 0.05; }
    100% { stroke-dashoffset: 0;    fill-opacity: 1; }
}

.prologue-text {
    font-family: var(--body-font);
    font-style: italic;
    font-size: 1.25rem;
    color: var(--sumi);
    margin: 3vh 0 5vh 0;
    max-width: 36ch;
}

/* ---------------- year heading ---------------- */
.year-heading {
    font-family: var(--display-font);
    font-weight: 500;
    margin: 0 0 4vh 0;
    line-height: 1;
    letter-spacing: 0.04em;
    display: flex;
    align-items: baseline;
    gap: 1.4vw;
    flex-wrap: wrap;
}
.align-right .year-heading { justify-content: flex-end; }
.align-center .year-heading { justify-content: center; }

.kanji-num {
    font-family: var(--num-font);
    font-weight: 700;
    font-size: clamp(2.6rem, 5.4vw, 4.2rem);
    color: var(--sumi);
    display: inline-block;
    transform: rotate(-1.5deg) scale(0.92);
    opacity: 0;
    transition: transform 1400ms var(--ease-ink), opacity 1100ms var(--ease-ink);
}
.is-visible .kanji-num {
    transform: rotate(0deg) scale(1);
    opacity: 1;
}

.latin-num {
    font-family: var(--latin-num);
    font-weight: 300;
    font-size: clamp(1.1rem, 1.8vw, 1.4rem);
    color: var(--kuwacha);
    letter-spacing: 0.18em;
    padding-left: 0.3em;
    border-left: 1px solid rgba(139, 111, 71, 0.4);
}

.year-heading--indigo .kanji-num { color: var(--kachi); }
.year-heading--indigo .latin-num { color: var(--kachi); border-left-color: rgba(44, 58, 74, 0.45); }

/* ---------------- memory text ---------------- */
.memory-text {
    font-family: var(--body-font);
    font-size: 1.0625rem;
    line-height: 1.85;
    color: var(--sumi);
    max-width: 38ch;
    margin-bottom: 3.4vh;
}
.align-right .memory-text { margin-left: auto; }
.align-center .memory-text { margin-left: auto; margin-right: auto; }
.memory-text em { color: var(--kuwacha); font-style: italic; }
.memory-text--solemn { color: var(--kachi); font-style: italic; }

/* ---------------- tanka caption ---------------- */
.tanka {
    display: flex;
    flex-direction: column;
    font-family: var(--hand-font);
    font-size: 1.125rem;
    color: var(--moegi);
    font-weight: 400;
    line-height: 1.5;
    padding-left: 2vw;
    border-left: 1px solid rgba(93, 107, 84, 0.32);
    margin-top: 2vh;
}
.tanka.align-end {
    align-items: flex-end;
    padding-left: 0;
    padding-right: 2vw;
    border-left: none;
    border-right: 1px solid rgba(93, 107, 84, 0.32);
    text-align: right;
}
.tanka span {
    display: block;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 900ms var(--ease-ink), transform 900ms var(--ease-ink);
}
.is-visible .tanka span:nth-child(1) { opacity: 1; transform: none; transition-delay: 380ms; }
.is-visible .tanka span:nth-child(2) { opacity: 1; transform: none; transition-delay: 500ms; }
.is-visible .tanka span:nth-child(3) { opacity: 1; transform: none; transition-delay: 640ms; }

/* ---------------- artifact frame ---------------- */
.artifact-frame {
    position: relative;
    margin: 2vh 0 3vh 0;
    width: clamp(180px, 22vw, 280px);
    padding: 14px;
    background: rgba(244, 237, 224, 0.5);
    border: 1px solid rgba(139, 111, 71, 0.18);
    box-shadow:
        inset 0 0 0 1px rgba(244, 237, 224, 0.6),
        2px 3px 0 rgba(58, 52, 46, 0.04);
    transform: rotate(var(--frame-tilt, -0.4deg));
}
.align-right .artifact-frame { margin-left: auto; transform: rotate(var(--frame-tilt, 0.6deg)); }

.artifact {
    width: 100%;
    height: auto;
    display: block;
    filter: sepia(0.18) saturate(0.85) contrast(1.02);
    opacity: 0.94;
    transition: opacity 1400ms var(--ease-ink);
}
.is-visible .artifact { opacity: 1; }

/* corner ink splatters */
.splatter {
    position: absolute;
    width: 22px;
    height: 22px;
    pointer-events: none;
    background-image: var(--splat-bg);
    background-size: contain;
    background-repeat: no-repeat;
    opacity: 0.55;
}
.splatter--tl { top: -8px; left: -8px; transform: rotate(var(--splat-tl-r, 12deg)); }
.splatter--br { bottom: -8px; right: -8px; transform: rotate(var(--splat-br-r, -18deg)); }

/* ---------------- year stamp (hanko) ---------------- */
.year-stamp {
    position: absolute;
    top: 18vh;
    left: calc(var(--rail-x) - 4.6vw);
    width: 56px;
    height: 56px;
    z-index: 5;
    opacity: 0;
    transform: scale(0.92) rotate(-3deg);
    transition: opacity 900ms var(--ease-ink), transform 900ms var(--ease-ink);
}
.year-stamp svg { width: 100%; height: 100%; }
.year-stamp svg rect { fill: var(--shu); opacity: 0.86; }

.is-visible.panel .year-stamp,
.year-stamp.is-pressed {
    opacity: 1;
    transform: scale(1) rotate(0deg);
    animation: stampPress 900ms var(--ease-ink) 200ms 1;
}
@keyframes stampPress {
    0%   { transform: scale(1) rotate(0deg); }
    35%  { transform: scale(0.96) rotate(-1deg); box-shadow: 0 0 0 2px rgba(168, 50, 50, 0.18); }
    70%  { transform: scale(1.01) rotate(0.4deg); }
    100% { transform: scale(1) rotate(0deg); }
}

.year-stamp--marked svg rect { fill: var(--shu); }
.year-stamp--marked { width: 64px; height: 64px; }

/* ---------------- hanko on prologue ---------------- */
.hanko {
    width: 84px;
    height: 84px;
    margin-top: 4vh;
}
.hanko svg { width: 100%; height: 100%; }
.hanko svg rect { fill: var(--shu); opacity: 0.9; }

/* ---------------- kanji watermark ---------------- */
.kanji-watermark {
    position: absolute;
    top: 50%;
    right: 8vw;
    transform: translateY(-50%);
    font-family: var(--display-font);
    font-weight: 500;
    font-size: 22vw;
    line-height: 1;
    color: var(--kuwacha);
    opacity: 0.09;
    pointer-events: none;
    user-select: none;
    z-index: 4;
    transition: opacity 1600ms var(--ease-ink);
}
.watermark-spring  { color: var(--moegi); opacity: 0.10; }
.watermark-summer  { color: var(--moegi); opacity: 0.08; }
.watermark-autumn  { color: var(--kuwacha-2); opacity: 0.10; }
.watermark-winter  { color: var(--kachi); opacity: 0.09; }
.watermark-reiwa   { color: var(--shu); opacity: 0.08; font-size: 18vw; }

/* ---------------- siren waveform ---------------- */
.siren-wave {
    margin-top: 3vh;
    width: 100%;
    height: 60px;
    opacity: 0;
    transition: opacity 1800ms var(--ease-ink) 600ms;
}
.is-visible .siren-wave { opacity: 0.7; }
.siren-wave svg { width: 100%; height: 100%; }
.siren-wave svg path {
    stroke-dasharray: 1400;
    stroke-dashoffset: 1400;
}
.is-visible .siren-wave svg path {
    animation: drawWave 2400ms var(--ease-ink) 800ms forwards;
}
@keyframes drawWave {
    to { stroke-dashoffset: 0; }
}

/* ---------------- scroll cue ---------------- */
.scroll-cue {
    position: absolute;
    bottom: 5vh;
    left: var(--rail-x);
    width: 1px;
    height: 60px;
    overflow: hidden;
}
.scroll-cue span {
    display: block;
    width: 1px;
    height: 60px;
    background: linear-gradient(to bottom, transparent, var(--kuwacha));
    animation: scrollCue 2400ms var(--ease-ink) infinite;
}
@keyframes scrollCue {
    0%   { transform: translateY(-60px); opacity: 0; }
    30%  { opacity: 1; }
    100% { transform: translateY(60px); opacity: 0; }
}

/* ============================================
   INTERLUDES (full bleed seasonal scenes)
   ============================================ */
.interlude {
    width: 100%;
    min-height: 90vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 8vh 0;
    position: relative;
    overflow: hidden;
}
.interlude-line {
    position: relative;
    z-index: 8;
    font-family: var(--display-font);
    font-size: clamp(1.2rem, 2.4vw, 1.8rem);
    color: var(--sumi);
    font-weight: 500;
    letter-spacing: 0.05em;
    text-align: center;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 1400ms var(--ease-ink), transform 1400ms var(--ease-ink);
    padding: 2vh 4vw;
    background: rgba(244, 237, 224, 0.6);
    backdrop-filter: blur(0.5px);
}
.is-visible .interlude-line { opacity: 1; transform: none; }

.interlude-scene {
    position: absolute;
    inset: 0;
    z-index: 1;
}

/* --- blossom interlude --- */
.blossom-sky {
    position: absolute;
    inset: 0;
    background: linear-gradient(
        to bottom,
        #f0e5d4 0%,
        #e8dcc4 50%,
        rgba(168, 50, 50, 0.05) 100%
    );
}
.petal {
    position: absolute;
    top: -3%;
    left: var(--x);
    width: 14px;
    height: 18px;
    background: radial-gradient(ellipse at 50% 30%, #d4b896 0%, #a83232 100%);
    border-radius: 50% 12% 50% 12%;
    opacity: 0.55;
    animation: petalFall 14s var(--ease-ink) infinite;
    animation-delay: var(--d, 0s);
    transform: rotate(var(--r, 0deg));
}
@keyframes petalFall {
    0%   { transform: translateY(0) rotate(0deg); opacity: 0; }
    10%  { opacity: 0.55; }
    100% { transform: translateY(110vh) rotate(720deg); opacity: 0; }
}

/* --- neon interlude --- */
.interlude-scene--neon { background: var(--kachi); }
.neon-sky {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 70% 30%, rgba(168, 50, 50, 0.18) 0%, transparent 50%),
        radial-gradient(circle at 30% 60%, rgba(212, 184, 150, 0.12) 0%, transparent 50%),
        linear-gradient(to bottom, #1d2733 0%, #2c3a4a 60%, #3a342e 100%);
}
.neon-strip {
    position: absolute;
    bottom: 30%;
    left: 0;
    right: 0;
    height: 28px;
    display: flex;
    justify-content: space-around;
    align-items: center;
}
.neon-strip--lower { bottom: 14%; }
.neon-strip span {
    display: block;
    width: 60px;
    height: 8px;
    background: var(--shu);
    box-shadow: 0 0 12px rgba(168, 50, 50, 0.6);
    opacity: 0.85;
    animation: neonFlicker 4.5s var(--ease-ink) infinite;
}
.neon-strip span:nth-child(2) { background: var(--hikari); box-shadow: 0 0 12px rgba(212, 184, 150, 0.6); animation-delay: 0.4s; }
.neon-strip span:nth-child(3) { background: var(--moegi); box-shadow: 0 0 12px rgba(93, 107, 84, 0.6); animation-delay: 0.8s; }
.neon-strip span:nth-child(4) { background: var(--shu); animation-delay: 1.2s; }
.neon-strip span:nth-child(5) { background: var(--hikari); animation-delay: 1.6s; }
.neon-strip span:nth-child(6) { background: var(--moegi); animation-delay: 2.0s; }

@keyframes neonFlicker {
    0%, 92%, 100% { opacity: 0.85; }
    93%           { opacity: 0.45; }
    95%           { opacity: 0.9; }
}

.interlude--neon .interlude-line {
    color: var(--kinari);
    background: rgba(44, 58, 74, 0.55);
}

/* --- autumn --- */
.interlude-scene--autumn { background: linear-gradient(to bottom, #d4b896 0%, #b89c70 60%, #7a6852 100%); }
.autumn-sky {
    position: absolute;
    inset: 0 0 40% 0;
    background: linear-gradient(to bottom, #e8dcc4, #d4b896);
}
.autumn-field {
    position: absolute;
    inset: 60% 0 0 0;
    background: linear-gradient(
        to bottom,
        #b89c70 0%,
        #8b6f47 70%,
        #7a6852 100%
    );
}
.autumn-field::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        repeating-linear-gradient(
            85deg,
            transparent 0,
            transparent 14px,
            rgba(58, 52, 46, 0.06) 14px,
            rgba(58, 52, 46, 0.06) 16px
        );
}
.leaf {
    position: absolute;
    top: -5%;
    left: var(--lx);
    width: 12px;
    height: 14px;
    background: linear-gradient(135deg, var(--shu) 0%, var(--kuwacha-2) 100%);
    border-radius: 0 60% 0 60%;
    opacity: 0.6;
    animation: leafFall 12s var(--ease-ink) infinite;
    animation-delay: var(--ld, 0s);
}
@keyframes leafFall {
    0%   { transform: translateY(0) rotate(0deg); opacity: 0; }
    10%  { opacity: 0.6; }
    100% { transform: translateY(105vh) rotate(540deg); opacity: 0; }
}

/* --- winter coastline --- */
.interlude-scene--winter {
    background: linear-gradient(to bottom, #e8dcc4 0%, #c5cdd0 50%, #2c3a4a 100%);
}
.winter-sky {
    position: absolute;
    inset: 0 0 50% 0;
    background: linear-gradient(to bottom, #f0e5d4, #c5cdd0);
}
.winter-sea {
    position: absolute;
    inset: 50% 0 0 0;
    background: linear-gradient(to bottom, #2c3a4a, #1d2733);
}
.winter-horizon {
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 1px;
    background: rgba(244, 237, 224, 0.55);
}
.winter-sea::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        repeating-linear-gradient(
            175deg,
            transparent 0,
            transparent 20px,
            rgba(244, 237, 224, 0.04) 20px,
            rgba(244, 237, 224, 0.04) 22px
        );
}
.interlude--winter-mid .interlude-line {
    color: var(--kinari);
    background: rgba(44, 58, 74, 0.5);
}

/* ============================================
   EPILOGUE
   ============================================ */
.seal-transition {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 3vw;
    margin: 6vh 0;
}
.seal {
    width: 96px;
    height: 96px;
    transition: opacity 1600ms var(--ease-ink), filter 1600ms var(--ease-ink);
}
.seal svg { width: 100%; height: 100%; }
.seal svg rect { fill: var(--shu); opacity: 0.85; }

.seal--heisei { opacity: 0.45; filter: grayscale(0.4); }
.seal--reiwa { opacity: 0; transform: scale(0.92) rotate(-2deg); transition: opacity 1800ms var(--ease-ink) 800ms, transform 1800ms var(--ease-ink) 800ms; }
.is-visible .seal--reiwa { opacity: 1; transform: scale(1) rotate(0deg); }

.seal-arrow {
    font-family: var(--display-font);
    font-size: 2.2rem;
    color: var(--kuwacha);
    opacity: 0;
    transition: opacity 1400ms var(--ease-ink) 400ms;
}
.is-visible .seal-arrow { opacity: 0.75; }

.epilogue-text {
    font-family: var(--body-font);
    font-style: italic;
    font-size: 1.2rem;
    color: var(--sumi);
    max-width: 42ch;
    margin: 4vh auto;
    line-height: 1.85;
}

.footer-line {
    font-family: var(--display-font);
    font-weight: 500;
    font-size: clamp(1.4rem, 2.6vw, 2rem);
    color: var(--sumi);
    letter-spacing: 0.08em;
    margin-top: 8vh;
    line-height: 1.5;
}
.footer-translation {
    font-family: var(--body-font);
    font-style: italic;
    font-size: 1rem;
    color: var(--kuwacha);
    margin-top: 1.5vh;
    letter-spacing: 0.04em;
}

.cookie-note {
    margin-top: 8vh;
    font-family: var(--hand-font);
    font-size: 0.85rem;
    color: var(--kuwacha);
    opacity: 0.7;
    line-height: 1.6;
    max-width: 48ch;
    margin-left: auto;
    margin-right: auto;
}

/* ============================================
   per-panel solemn variant
   ============================================ */
.panel--final {
    background: linear-gradient(
        to bottom,
        var(--kinari) 0%,
        var(--reiwa-bg) 100%
    );
}
.panel--final .memory-text--solemn { color: var(--kachi); }

/* small screen fallbacks */
@media (max-width: 720px) {
    .kanji-watermark { font-size: 28vw; right: 4vw; }
    .year-stamp { left: 4vw; width: 44px; height: 44px; }
    .timeline-spine { display: none; }
    .interlude { min-height: 70vh; }
    .seal { width: 72px; height: 72px; }
    .seal-arrow { font-size: 1.6rem; }
}