:root {
    --ink: #1a1623;
    --paper: #f7f2e9;
    --paper-2: #efe7d6;
    --red: #e3392f;
    --red-deep: #b32419;
    --indigo: #2a2a4a;
    --gold: #d9a441;
    --line: #d8cdb6;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Zen Maru Gothic', system-ui, sans-serif;
    color: var(--ink);
    background-color: var(--paper);
    background-image:
        radial-gradient(circle at 1px 1px, rgba(26,22,35,0.06) 1px, transparent 0);
    background-size: 22px 22px;
    line-height: 1.7;
    overflow-x: hidden;
}

/* Retro rising sun behind hero */
.sun {
    position: absolute;
    top: -180px;
    left: 50%;
    transform: translateX(-50%);
    width: 520px;
    height: 520px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--red) 0%, var(--red) 60%, var(--red-deep) 100%);
    opacity: 0.10;
    z-index: 0;
    pointer-events: none;
}

/* ---------- Hero ---------- */
.hero {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 64px 24px 40px;
    max-width: 880px;
    margin: 0 auto;
}

.kana {
    font-family: 'Shippori Mincho', serif;
    letter-spacing: 0.5em;
    color: var(--red);
    font-size: 0.9rem;
    margin-bottom: 18px;
    opacity: 0.85;
}

.venue {
    display: inline-block;
    font-family: 'Zen Dots', sans-serif;
    font-size: 0.62rem;
    letter-spacing: 0.1em;
    color: var(--paper);
    background: var(--indigo);
    padding: 6px 14px;
    border-radius: 2px;
    margin-bottom: 22px;
    max-width: 100%;
    line-height: 1.4;
}

.title {
    font-family: 'Zen Dots', sans-serif;
    font-size: clamp(2.6rem, 8vw, 4.6rem);
    line-height: 1;
    letter-spacing: 0.01em;
    color: var(--ink);
}

.title .six {
    color: var(--red);
}

.subtitle {
    font-family: 'Shippori Mincho', serif;
    font-size: clamp(1rem, 2.4vw, 1.25rem);
    margin-top: 18px;
    color: #4a4357;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 14px;
    margin-top: 32px;
}

.download-btn {
    display: inline-block;
    font-family: 'Zen Maru Gothic', sans-serif;
    font-weight: 700;
    font-size: 1.05rem;
    letter-spacing: 0.04em;
    text-decoration: none;
    color: var(--paper);
    background: var(--red);
    padding: 14px 38px;
    border-radius: 4px;
    box-shadow: 5px 5px 0 var(--ink);
    transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.2s ease;
}

.download-btn:hover {
    background: var(--red-deep);
    transform: translate(2px, 2px);
    box-shadow: 3px 3px 0 var(--ink);
}

.paper-chip {
    display: inline-block;
    font-family: 'Zen Dots', sans-serif;
    font-size: 0.72rem;
    letter-spacing: 0.14em;
    text-decoration: none;
    color: var(--ink);
    background: var(--paper-2);
    border: 2px solid var(--ink);
    padding: 12px 22px;
    border-radius: 4px;
    box-shadow: 4px 4px 0 var(--ink);
    transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.2s ease;
}

.paper-chip:hover {
    background: var(--paper);
    transform: translate(2px, 2px);
    box-shadow: 2px 2px 0 var(--ink);
}

/* ---------- Sections ---------- */
main {
    position: relative;
    z-index: 1;
    max-width: 880px;
    margin: 0 auto;
    padding: 0 24px;
}

.teaser {
    margin: 28px 0 56px;
}

.teaser img {
    width: 100%;
    height: auto;
    display: block;
    border: 3px solid var(--ink);
    border-radius: 4px;
    box-shadow: 8px 8px 0 rgba(26,22,35,0.12);
}

.caption {
    font-family: 'Shippori Mincho', serif;
    font-size: 0.85rem;
    color: #6a6276;
    text-align: center;
    margin-top: 14px;
    font-style: italic;
}

.block {
    margin: 0 0 64px;
}

h2 {
    font-family: 'Zen Maru Gothic', sans-serif;
    font-weight: 700;
    font-size: 1.6rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--line);
    display: flex;
    align-items: center;
    gap: 14px;
}

.mark {
    font-family: 'Shippori Mincho', serif;
    font-size: 1.25rem;
    color: var(--paper);
    background: var(--red);
    padding: 4px 10px;
    border-radius: 3px;
    line-height: 1;
}

.block p {
    margin-bottom: 16px;
    font-size: 1.02rem;
}

/* ---------- Metrics ---------- */
.metrics {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 14px;
    margin-top: 30px;
}

.metric {
    background: var(--paper-2);
    border: 2px solid var(--ink);
    border-radius: 4px;
    text-align: center;
    padding: 18px 8px;
}

.metric .val {
    display: block;
    font-family: 'Zen Dots', sans-serif;
    font-size: 1.5rem;
    color: var(--red);
}

.metric .lbl {
    display: block;
    font-size: 0.78rem;
    letter-spacing: 0.12em;
    color: #4a4357;
    margin-top: 6px;
}

/* ---------- Challenge ---------- */
.challenge-grid {
    display: grid;
    grid-template-columns: 1fr 1.1fr;
    gap: 24px;
    align-items: center;
}

.challenge-grid img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border: 3px solid var(--ink);
    border-radius: 4px;
    box-shadow: 6px 6px 0 rgba(26,22,35,0.12);
}

.prizes {
    font-weight: 700;
    color: var(--red-deep);
}

/* ---------- Related ---------- */
.related-list {
    list-style: none;
}

.related-list li {
    background: var(--paper-2);
    border-left: 5px solid var(--red);
    padding: 14px 18px;
    border-radius: 0 4px 4px 0;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    flex-wrap: wrap;
}

.related-list li + li {
    margin-top: 12px;
}

.related-list a {
    color: var(--ink);
    text-decoration: none;
    border-bottom: 1px solid transparent;
}

.related-list a:hover {
    border-bottom-color: var(--red);
}

.badge {
    font-family: 'Zen Dots', sans-serif;
    font-size: 0.62rem;
    letter-spacing: 0.12em;
    color: var(--paper);
    background: var(--indigo);
    padding: 4px 9px;
    border-radius: 2px;
    white-space: nowrap;
}

/* ---------- Dataset notice ---------- */
.dataset-notice {
    font-size: 0.75rem;
    line-height: 1.55;
    color: #6a6276;
    text-align: center;
    max-width: 640px;
    margin: -32px auto 48px;
    padding: 0 8px;
}

/* ---------- Footer ---------- */
footer {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 40px 24px 56px;
    border-top: 2px solid var(--line);
    margin-top: 24px;
    font-size: 0.9rem;
    color: #6a6276;
}

/* ---------- Responsive ---------- */
@media (max-width: 640px) {
    .metrics { grid-template-columns: repeat(2, 1fr); }
    .challenge-grid { grid-template-columns: 1fr; }
    .sun { width: 340px; height: 340px; top: -120px; }
}