:root {
    --bg-dark: #07121a;
    --bg-deep: #163548;
    --surface: rgba(255, 250, 244, 0.9);
    --surface-soft: rgba(228, 242, 247, 0.84);
    --surface-warm: rgba(255, 239, 216, 0.9);
    --ink: #1d2834;
    --muted: #66717c;
    --line: rgba(29, 40, 52, 0.12);
    --accent: #28706d;
    --accent-strong: #163548;
    --accent-soft: #cf8d45;
    --success: #1b8d58;
    --danger: #c23c57;
    --shadow: 0 28px 64px rgba(7, 18, 26, 0.22);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-height: 100vh;
    color: var(--ink);
    font-family: "IBM Plex Sans JP", sans-serif;
    background:
        radial-gradient(circle at 12% 10%, rgba(207, 141, 69, 0.2), transparent 20%),
        radial-gradient(circle at 84% 12%, rgba(40, 112, 109, 0.24), transparent 22%),
        linear-gradient(180deg, #051019 0%, #163548 17%, #eee5d8 17.1%, #f6efe6 100%);
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 50px 50px;
    mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.82), rgba(0, 0, 0, 0.08));
}

a {
    color: inherit;
    text-decoration: none;
}

button,
input {
    font: inherit;
}

canvas {
    display: block;
    cursor: crosshair;
}

.page-shell {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding-bottom: 80px;
}

.site-header {
    position: sticky;
    top: 14px;
    z-index: 20;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    margin: 18px 0 20px;
    padding: 16px 22px;
    border-radius: 999px;
    background: rgba(5, 13, 20, 0.78);
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(18px);
    box-shadow: 0 16px 38px rgba(0, 0, 0, 0.24);
}

.brand,
h1,
h2,
h3,
.signal-main,
.footer-title {
    font-family: "Shippori Mincho", serif;
}

.brand {
    color: #f7efe1;
    font-size: 1.14rem;
    letter-spacing: 0.08em;
}

.site-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 18px;
    color: rgba(247, 239, 225, 0.84);
    font-size: 0.95rem;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.footer-links a:hover,
.footer-links a:focus-visible {
    color: white;
}

.section,
.signal-strip,
.site-footer {
    opacity: 0;
    transform: translateY(26px);
    transition: opacity 520ms ease, transform 520ms ease;
}

.reveal.is-visible,
.site-footer.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.stage {
    display: grid;
    gap: 20px;
    padding: 34px 0 22px;
}

.stage-copy,
.signal-strip,
.rule-card,
.pattern-card,
.related-card,
.site-footer {
    border: 1px solid rgba(255, 255, 255, 0.58);
    background: var(--surface);
    box-shadow: var(--shadow);
    backdrop-filter: blur(14px);
}

.stage-copy {
    padding: 28px 28px 24px;
    border-radius: 32px;
    position: relative;
    overflow: hidden;
}

.stage-copy::after {
    content: "";
    position: absolute;
    inset: auto -54px -110px auto;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(207, 141, 69, 0.38), rgba(207, 141, 69, 0));
}

.eyebrow,
.card-label,
.signal-kicker {
    margin: 0 0 12px;
    color: var(--accent-strong);
    font-size: 0.84rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

h1,
h2,
h3,
.brand {
    line-height: 1.14;
}

h1,
h2 {
    margin: 0;
}

h1 {
    font-size: clamp(2.7rem, 5vw, 4.8rem);
    letter-spacing: -0.04em;
}

.stage-lead,
.section-heading p,
.rule-card p,
.pattern-card p,
.related-card p,
.signal-sub,
.site-footer p,
.panel-header p,
.panel-status,
.floating-hint,
.stage-stats span,
.stat-box,
.pattern-header span {
    color: var(--muted);
}

.stage-lead {
    margin: 18px 0 0;
    max-width: 780px;
    font-size: 1.04rem;
    line-height: 1.8;
}

.stage-tags,
.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.stage-tags {
    margin-top: 22px;
    position: relative;
    z-index: 1;
}

.stage-tags span {
    padding: 10px 14px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.74);
    border: 1px solid rgba(22, 53, 72, 0.12);
    color: var(--accent-strong);
    font-weight: 600;
}

.simulation-shell {
    order: -1;
    position: relative;
    min-height: clamp(680px, 80vh, 860px);
    border-radius: 38px;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.16);
    box-shadow: 0 32px 64px rgba(4, 9, 18, 0.34);
    background:
        radial-gradient(circle at 50% 40%, rgba(16, 36, 53, 0.82), rgba(2, 8, 15, 0.98)),
        linear-gradient(180deg, rgba(3, 8, 15, 0.96), rgba(5, 12, 22, 0.98));
}

.simulation-shell::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 14% 18%, rgba(45, 212, 191, 0.08), transparent 18%),
        radial-gradient(circle at 84% 14%, rgba(250, 204, 21, 0.08), transparent 18%);
    pointer-events: none;
}

#lifeCanvas {
    width: 100%;
    height: 100%;
}

.panel,
.floating-hint,
.stage-stats article {
    position: absolute;
    z-index: 2;
    background: rgba(2, 6, 23, 0.78);
    border: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(18px);
    box-shadow: 0 18px 36px rgba(0, 0, 0, 0.28);
}

.panel {
    top: 22px;
    left: 22px;
    width: min(362px, calc(100% - 44px));
    padding: 18px;
    border-radius: 24px;
    color: #f8fbff;
}

.panel-header h2 {
    margin: 0;
    font-size: 1.15rem;
}

.panel-header p {
    margin: 8px 0 0;
    font-size: 0.9rem;
    line-height: 1.6;
}

.row,
.patterns {
    display: grid;
    gap: 10px;
    margin-top: 14px;
}

.row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.patterns {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.control {
    margin-top: 14px;
}

.control label {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 6px;
    color: #edf3fb;
    font-size: 0.9rem;
}

.control input[type="range"] {
    width: 100%;
    accent-color: #5eead4;
}

.pattern-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-top: 14px;
}

.pattern-header p {
    margin: 0;
    color: #edf3fb;
    font-size: 0.9rem;
}

.pattern-header span {
    font-size: 0.82rem;
}

button,
.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 0 16px;
    border-radius: 999px;
    border: 1px solid transparent;
    cursor: pointer;
    transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease, border-color 180ms ease;
}

button:hover,
button:focus-visible,
.button:hover,
.button:focus-visible,
.related-card:hover,
.related-card:focus-within {
    transform: translateY(-2px);
}

.panel button {
    color: white;
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.16);
}

.panel button.active,
.button-primary {
    background: linear-gradient(135deg, var(--accent), var(--accent-strong));
    border-color: transparent;
    box-shadow: 0 12px 24px rgba(22, 53, 72, 0.24);
}

.panel button.green {
    background: linear-gradient(135deg, var(--success), #0f6b43);
    border-color: transparent;
    box-shadow: 0 12px 24px rgba(15, 107, 67, 0.24);
}

.panel button.red {
    background: linear-gradient(135deg, var(--danger), #8d1d34);
    border-color: transparent;
    box-shadow: 0 12px 24px rgba(141, 29, 52, 0.24);
}

.panel button.yellow {
    background: linear-gradient(135deg, #ca8a04, #9a6700);
    border-color: transparent;
    box-shadow: 0 12px 24px rgba(154, 103, 0, 0.24);
}

.button-secondary {
    background: rgba(255, 255, 255, 0.8);
    border-color: var(--line);
}

.stats {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
    margin-top: 14px;
}

.stat-box {
    padding: 10px 12px;
    border-radius: 14px;
    background: rgba(15, 23, 42, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.08);
    font-size: 0.84rem;
    color: #d7e4f0;
}

.stat-box span {
    color: white;
    font-weight: 700;
}

.panel-status {
    margin: 14px 0 0;
    font-size: 0.88rem;
    line-height: 1.6;
}

.floating-hint {
    right: 22px;
    bottom: 22px;
    max-width: 380px;
    padding: 12px 14px;
    border-radius: 18px;
    color: #dfe9f5;
    font-size: 0.88rem;
    line-height: 1.55;
}

.stage-stats {
    position: absolute;
    top: 22px;
    right: 22px;
    z-index: 2;
    width: min(290px, calc(100% - 426px));
    display: grid;
    gap: 10px;
}

.stage-stats article {
    padding: 12px 14px;
    border-radius: 18px;
    color: #f8fbff;
}

.stage-stats span {
    display: block;
    font-size: 0.8rem;
    margin-bottom: 6px;
}

.stage-stats strong {
    font-size: 1.05rem;
}

.signal-strip {
    margin-top: 14px;
    padding: 24px 28px;
    border-radius: 28px;
}

.signal-kicker {
    margin-bottom: 10px;
}

.signal-main {
    margin: 0;
    font-size: clamp(1.5rem, 2.7vw, 2.35rem);
}

.signal-sub {
    margin: 12px 0 0;
    max-width: 900px;
    line-height: 1.8;
}

.section {
    padding-top: 62px;
}

.section-heading {
    max-width: 760px;
}

.section-heading h2 {
    font-size: clamp(2rem, 3.4vw, 3rem);
    letter-spacing: -0.03em;
}

.section-heading p:last-child {
    margin: 16px 0 0;
    line-height: 1.8;
}

.rule-grid,
.pattern-grid,
.related-grid {
    display: grid;
    gap: 18px;
    margin-top: 24px;
}

.rule-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.pattern-grid,
.related-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.rule-card,
.pattern-card,
.related-card {
    padding: 24px;
    border-radius: 28px;
}

.strong-card {
    background: linear-gradient(180deg, rgba(229, 244, 244, 0.92), rgba(255, 250, 244, 0.88));
}

.warm-card {
    background: linear-gradient(180deg, rgba(255, 242, 223, 0.94), rgba(255, 250, 244, 0.88));
}

.accent-card,
.feature-card {
    background: linear-gradient(180deg, rgba(22, 53, 72, 0.96), rgba(40, 112, 109, 0.88));
    color: #f7fbff;
}

.accent-card p,
.feature-card p,
.feature-card .card-label,
.accent-card .card-label {
    color: rgba(239, 246, 255, 0.84);
}

.rule-card h3,
.pattern-card h3,
.related-card h3 {
    margin: 0;
    font-size: 1.32rem;
}

.rule-card p,
.pattern-card p,
.related-card p {
    margin: 12px 0 0;
    line-height: 1.75;
}

.button {
    margin-top: 18px;
}

.site-footer {
    margin-top: 72px;
    padding: 28px;
    border-radius: 32px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}

.footer-title {
    margin: 0;
    font-size: 1.12rem;
}

.site-footer p {
    margin: 10px 0 0;
    max-width: 700px;
    line-height: 1.7;
}

@media (max-width: 1080px) {
    .pattern-grid,
    .related-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 860px) {
    .page-shell {
        width: min(100%, calc(100% - 24px));
    }

    .simulation-shell {
        min-height: auto;
        display: grid;
        grid-template-columns: 1fr;
        grid-template-areas:
            "canvas"
            "stats"
            "panel"
            "hint";
        align-content: start;
        gap: 14px;
        padding: 18px;
        overflow: visible;
    }

    #lifeCanvas {
        grid-area: canvas;
        position: relative;
        z-index: 1;
        height: clamp(340px, 54vh, 520px);
        border-radius: 24px;
    }

    .panel,
    .stage-stats,
    .floating-hint,
    .stage-stats article {
        position: relative;
        inset: auto;
        top: auto;
        right: auto;
        bottom: auto;
        left: auto;
        width: auto;
        max-width: none;
    }

    .panel {
        grid-area: panel;
    }

    .stage-stats {
        grid-area: stats;
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .floating-hint {
        grid-area: hint;
    }

    .rule-grid,
    .pattern-grid,
    .related-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .site-header,
    .site-footer,
    .stage-copy,
    .signal-strip,
    .rule-card,
    .pattern-card,
    .related-card {
        border-radius: 24px;
    }

    .site-header {
        padding: 14px 16px;
    }

    .stage-copy {
        padding: 24px 20px 20px;
    }

    h1 {
        font-size: clamp(2.15rem, 12vw, 3.1rem);
    }

    .simulation-shell {
        gap: 12px;
        padding: 14px;
        border-radius: 28px;
    }

    #lifeCanvas {
        height: clamp(280px, 50vh, 400px);
        border-radius: 20px;
    }

    .row,
    .patterns,
    .stats,
    .stage-stats {
        grid-template-columns: 1fr;
    }
}