/* concengine.com — muji-quiet observation room for concurrency */

:root {
    --paper-0: #F4F1EA;
    --paper-1: #FBF8F1;
    --paper-page: #FBF8F1;
    --ink-deep: #2A2A28;
    --ink-soft: #7A7872;
    --meridian: #E8E4DC;
    --sakura: #F6D3D7;
    --matcha: #D6E3CD;
    --asagi: #CFE0E6;
    --kohaku: #F2DDB8;
    --murasaki: #D8CCE0;
    --bengara: #E2B8B0;
    --kintsugi: #C9A961;

    --canvas-w: min(1320px, 92vw);
    --gutter-outer: clamp(56px, 8vw, 144px);
    --col-gap: 32px;
    --row-gap: clamp(48px, 6vw, 112px);

    --font-display: "Inter Tight", "Inter", system-ui, sans-serif;
    --font-prose: "Manrope", system-ui, sans-serif;
    --font-placard: "IBM Plex Sans Condensed", "IBM Plex Sans", sans-serif;
    --font-mincho: "Shippori Mincho", serif;
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    background: var(--paper-0);
    color: var(--ink-deep);
    font-family: var(--font-prose);
    font-size: 17px;
    line-height: 1.78;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

/* ---------- gradient mesh sky ---------- */
.mesh-sky {
    position: absolute;
    inset: 0 0 auto 0;
    z-index: 0;
    pointer-events: none;
    overflow: hidden;
    mix-blend-mode: multiply;
}

.mesh-sky--hero {
    height: 140vh;
    top: 0;
}

.mesh-sky svg {
    width: 100%;
    height: 100%;
    transform-origin: center center;
    animation: mesh-drift 240s linear infinite;
    opacity: 0.95;
}

@keyframes mesh-drift {
    0% { transform: rotate(0deg) scale(1.04) translate(0, 0); filter: hue-rotate(0deg); }
    50% { transform: rotate(8deg) scale(1.10) translate(-1.5%, 0.8%); filter: hue-rotate(12deg); }
    100% { transform: rotate(0deg) scale(1.04) translate(0, 0); filter: hue-rotate(0deg); }
}

/* repeated mesh region behind the ripple card */
.card--ripple::before,
.card--replay::before {
    content: "";
    position: absolute;
    inset: -36px;
    background:
        radial-gradient(60% 80% at 70% 30%, rgba(246, 211, 215, 0.16), transparent 60%),
        radial-gradient(60% 80% at 30% 70%, rgba(207, 224, 230, 0.18), transparent 60%),
        radial-gradient(80% 90% at 50% 50%, rgba(216, 204, 224, 0.12), transparent 70%);
    z-index: -1;
    pointer-events: none;
    mix-blend-mode: multiply;
}

/* ---------- meridian hairline at column 7 ---------- */
.meridian {
    position: absolute;
    top: 0;
    left: 50%;
    width: 0.5px;
    height: 100%;
    background: var(--meridian);
    z-index: 1;
    pointer-events: none;
    transform: translateX(calc(var(--canvas-w) * -0.5 + (var(--canvas-w) - 11 * var(--col-gap)) / 12 * 6 + 6 * var(--col-gap) - var(--col-gap) / 2));
}

@media (max-width: 900px) {
    .meridian {
        transform: translateX(calc(var(--canvas-w) * -0.5 + 100% * 0.58));
    }
}

/* ---------- left rail ---------- */
.rail {
    position: fixed;
    left: clamp(20px, 3vw, 48px);
    top: 50%;
    transform: translateY(-50%);
    z-index: 20;
    display: flex;
    flex-direction: column;
    gap: 28px;
    align-items: center;
}

.rail__glyph {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    text-decoration: none;
    opacity: 0.55;
    transition: opacity 0.4s ease;
}

.rail__glyph:hover,
.rail__glyph.is-active {
    opacity: 1;
}

@media (max-width: 720px) {
    .rail { display: none; }
}

/* ---------- canvas + grid ---------- */
.canvas {
    position: relative;
    z-index: 2;
    width: var(--canvas-w);
    margin: 0 auto;
    padding: clamp(72px, 9vw, 144px) 0 clamp(120px, 12vw, 200px);
}

.chapter {
    position: relative;
    padding: clamp(80px, 10vw, 180px) 0;
}

.grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    column-gap: var(--col-gap);
    row-gap: var(--row-gap);
    align-items: start;
}

/* card footprints */
.card {
    position: relative;
    background: var(--paper-1);
    padding: clamp(28px, 3.6vw, 56px);
    border-radius: 3px;
    grid-column: span 5;
}

.card--small  { grid-column: span 3; min-height: 220px; }
.card--medium { grid-column: span 5; }
.card--large  { grid-column: span 7; }

.card--hero {
    grid-column: 7 / span 5;
    grid-row: span 2;
    aspect-ratio: 1.618 / 1;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    gap: 32px;
    padding: clamp(36px, 4.4vw, 72px);
}

/* "ma" emptiness — hero leaves col 1-6 blank by virtue of placement */

/* card placard tick */
.card__tick {
    display: inline-block;
    font-family: var(--font-placard);
    font-weight: 300;
    font-size: 11px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
    margin-bottom: 22px;
    padding-left: 14px;
    position: relative;
    transition: color 0.3s ease;
}

.card__tick::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    width: 8px;
    height: 1px;
    background: currentColor;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.card.is-glow .card__tick {
    color: #c47a83;
}
.card.is-glow .card__tick::before {
    background: var(--sakura);
    box-shadow: 0 0 0 2px rgba(246, 211, 215, 0.4);
}

/* ---------- enso mark ---------- */
.enso-mark {
    grid-column: 1 / span 4;
    display: flex;
    align-items: center;
    gap: 18px;
    margin-top: 20px;
}

.enso-mark__word {
    font-family: var(--font-display);
    font-weight: 380;
    font-size: 17px;
    letter-spacing: -0.01em;
    color: var(--ink-deep);
}

/* ---------- hero ---------- */
.hero__title {
    font-family: var(--font-display);
    font-weight: 320;
    font-size: clamp(54px, 8vw, 96px);
    line-height: 1.05;
    letter-spacing: -0.024em;
    color: var(--ink-deep);
    margin: 0;
    font-feature-settings: "ss01", "cv11";
}

.hero__waka {
    font-family: var(--font-prose);
    font-style: italic;
    font-size: 15px;
    line-height: 1.8;
    color: var(--ink-soft);
    margin: 0;
}

.hero__waka--inline {
    margin-top: 28px;
}

/* ---------- chapter heading ---------- */
.chapter__heading {
    grid-column: 2 / span 6;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.chapter__placard {
    font-family: var(--font-placard);
    font-weight: 300;
    font-size: 11px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
}

.heading {
    font-family: var(--font-display);
    font-weight: 320;
    font-size: clamp(32px, 4.4vw, 56px);
    line-height: 1.1;
    letter-spacing: -0.018em;
    color: var(--ink-deep);
    margin: 0;
    font-feature-settings: "ss01", "cv11";
}

.heading--mid {
    font-size: clamp(28px, 3.4vw, 44px);
    margin: 0 0 28px 0;
}

/* ---------- prose ---------- */
.prose {
    font-family: var(--font-prose);
    font-weight: 400;
    font-size: 17px;
    line-height: 1.78;
    color: var(--ink-deep);
    margin: 0 0 18px 0;
    max-width: 38em;
}

.prose--soft {
    color: var(--ink-soft);
    font-size: 15px;
}

/* ---------- caption ---------- */
.caption {
    font-family: var(--font-prose);
    font-style: italic;
    font-size: 13px;
    color: var(--ink-soft);
    margin: 14px 0 0 0;
}

.caption--centered { text-align: center; }
.caption--soft { color: var(--ink-soft); margin-top: 16px; font-size: 14px; }

/* ---------- specific cards ---------- */
.card--engine {
    grid-column: 1 / span 6;
}

.card--note {
    grid-column: 9 / span 4;
    background: var(--paper-1);
}

.card--vignette:nth-of-type(odd) { grid-column: 1 / span 4; }
.card--vignette:nth-of-type(even) { grid-column: 9 / span 4; }

.vignette {
    width: 100%;
    height: auto;
    margin-top: 8px;
}

.card--replay {
    grid-column: 3 / span 8;
    position: relative;
}

.replay__diagram {
    margin: 28px 0 18px;
    background: rgba(244, 241, 234, 0.5);
    padding: 18px 22px;
    border-radius: 2px;
}

.replay__svg {
    width: 100%;
    height: auto;
    display: block;
}

.replay__label {
    font-family: var(--font-placard);
    font-size: 10px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    fill: var(--ink-soft);
}

.replay__label--past { fill: #9b8aa6; }
.replay__label--right { text-anchor: end; }

/* ---------- ripple card ---------- */
.card--ripple {
    grid-column: 5 / span 6;
    text-align: center;
    position: relative;
}

.ripple-stage {
    display: flex;
    justify-content: center;
    margin: 12px auto 22px;
    width: 220px;
    height: 220px;
}

.ripple-svg { width: 100%; height: 100%; }

.ripple {
    stroke-dasharray: 480;
    stroke-dashoffset: 480;
    transition: stroke-dashoffset 1.2s cubic-bezier(0.22, 0.61, 0.36, 1);
}

.card--ripple.is-rippling .ripple--1 { stroke-dashoffset: 0; transition-delay: 0ms; }
.card--ripple.is-rippling .ripple--2 { stroke-dashoffset: 0; transition-delay: 120ms; }
.card--ripple.is-rippling .ripple--3 { stroke-dashoffset: 0; transition-delay: 240ms; }

.bignum {
    font-family: var(--font-display);
    font-weight: 320;
    font-size: 56px;
    line-height: 1;
    letter-spacing: -0.018em;
    color: var(--ink-deep);
    margin: 8px 0 6px;
    font-variant-numeric: tabular-nums;
    font-feature-settings: "tnum", "ss01";
}

.bignum__unit {
    font-size: 32px;
    color: var(--ink-soft);
    margin-left: 2px;
}

/* ---------- invite card ---------- */
.card--invite {
    grid-column: 4 / span 6;
}

.invite-field {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin: 24px 0 18px;
}

.invite-field__label {
    font-family: var(--font-placard);
    font-weight: 300;
    font-size: 11px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
}

.invite-field__input {
    font-family: var(--font-prose);
    font-size: 17px;
    line-height: 1.6;
    color: var(--ink-deep);
    background: var(--paper-0);
    border: 0.6px solid var(--meridian);
    border-radius: 2px;
    padding: 18px 22px;
    cursor: pointer;
    transition: background 0.6s ease, border-color 0.4s ease;
    width: 100%;
    max-width: 360px;
    font-variant-numeric: tabular-nums;
    font-feature-settings: "tnum";
}

.invite-field__input:hover {
    border-color: var(--ink-soft);
}

.invite-field__input.is-copied {
    background: var(--matcha);
    border-color: #b1c4a4;
}

/* ---------- kintsugi seam ---------- */
.kintsugi {
    grid-column: 1 / -1;
    margin-top: clamp(80px, 8vw, 140px);
    height: 14px;
    overflow: visible;
}

.kintsugi svg {
    width: 100%;
    height: 14px;
    overflow: visible;
}

.kintsugi__line {
    stroke-dasharray: 1300;
    stroke-dashoffset: 1300;
    transition: stroke-dashoffset 1.6s cubic-bezier(0.4, 0, 0.2, 1);
    opacity: 0.6;
}

.kintsugi.is-drawn .kintsugi__line {
    stroke-dashoffset: 0;
}

/* ---------- footer ---------- */
.footer {
    margin-top: clamp(80px, 8vw, 140px);
    padding: 40px 0;
}

.footer__row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.footer__placard {
    font-family: var(--font-placard);
    font-weight: 300;
    font-size: 11px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: var(--ink-soft);
}

.footer__placard--right { text-align: right; }

.footer__token {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--sakura);
    animation: token-drift 8s steps(8) infinite;
    transform-origin: center center;
    display: inline-block;
}

@keyframes token-drift {
    0%   { transform: translateX(-12px); opacity: 0.55; }
    50%  { transform: translateX(12px);  opacity: 1; }
    100% { transform: translateX(-12px); opacity: 0.55; }
}

/* ---------- cursor token (single tracker) ---------- */
.cursor-token {
    position: fixed;
    top: 0;
    left: 0;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--sakura);
    pointer-events: none;
    z-index: 30;
    opacity: 0;
    transition: opacity 0.6s ease;
    will-change: transform;
}

.cursor-token.is-visible { opacity: 1; }

/* ---------- responsive — collapse grid to a single column on small screens ---------- */
@media (max-width: 900px) {
    .grid {
        grid-template-columns: repeat(6, 1fr);
        column-gap: 20px;
    }
    .card,
    .card--small,
    .card--medium,
    .card--large,
    .card--hero,
    .card--engine,
    .card--note,
    .card--replay,
    .card--ripple,
    .card--invite {
        grid-column: 1 / -1;
    }
    .card--hero {
        aspect-ratio: auto;
        grid-row: auto;
    }
    .enso-mark {
        grid-column: 1 / -1;
    }
    .chapter__heading {
        grid-column: 1 / -1;
    }
    .card--vignette:nth-of-type(odd),
    .card--vignette:nth-of-type(even) {
        grid-column: 1 / -1;
    }
}

/* ---------- prefers-reduced-motion ---------- */
@media (prefers-reduced-motion: reduce) {
    .mesh-sky svg,
    .footer__token,
    .ripple,
    .kintsugi__line,
    .cursor-token,
    .invite-field__input {
        animation: none !important;
        transition: none !important;
    }
    .cursor-token { display: none; }
}