/* ===== ページの土台 ===== */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; }
img { max-width: 100%; }
[hidden] { display: none !important; }

/* 検出器のイベントディスプレイに合わせた、暗い1テーマ固定のデザイン */
:root {
  color-scheme: dark;
  --bg: #05070D;
  --bg-2: #0A0F1D;
  --bg-3: #10172B;
  --line: #1C2440;
  --line-2: #2A3558;
  --text: #E6EAF3;
  --text-2: #A7B0C6;
  --text-3: #8089A2;
  --accent: #A9BEDF;
  --p-proton: #EEF1F7;
  --p-higgs: #FFB547;
  --p-photon: #FFE066;
  --p-electron: #4DA3FF;
  --p-muon: #FF5C6C;
  --p-tau: #B388FF;
  --p-nue: #6EE7F9;
  --p-numu: #FF9ECF;
  --p-nutau: #D6B8FF;
  --p-z: #5EE6A0;
  --p-hadron: #8B95AB;
  --font-display: "Shippori Mincho", "Hiragino Mincho ProN", "Yu Mincho", "Noto Serif CJK JP", serif;
  --font-body: "IBM Plex Sans JP", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "Meiryo", "Noto Sans CJK JP", system-ui, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --font-sym: "STIX Two Text", "Cambria Math", "Times New Roman", serif;
}
body { background: var(--bg); color: var(--text); font-family: var(--font-body); font-size: 15px; line-height: 1.7; -webkit-font-smoothing: antialiased; }
.wrap { max-width: 1180px; margin-inline: auto; padding-inline: 20px; padding-block: 24px 44px; }
@media (max-width: 520px) { .wrap { padding-inline: 16px; } }
h1, h2, h3 { text-wrap: balance; font-feature-settings: "palt"; }
button { font-family: inherit; }
button:focus-visible, a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.sym { font-family: var(--font-sym); font-style: normal; }
sup, sub { font-size: .7em; line-height: 0; }

/* ---------- 見出し ---------- */
.top { display: grid; gap: 6px; margin-bottom: 16px; }
.crumbs { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: 12.5px; color: var(--text-3); }
.crumbs a { color: var(--text-2); text-decoration: none; }
.crumbs a:hover { color: var(--text); text-decoration: underline; text-underline-offset: 3px; }
h1 { margin: 0; font: 700 clamp(28px, 5vw, 40px)/1.15 var(--font-display); letter-spacing: .03em; }
.lede { margin: 0; max-width: 46em; font-size: 14.5px; color: var(--text-2); }

/* ---------- 場面タブ ---------- */
.tabs { display: flex; gap: 2px; margin-bottom: 16px; overflow-x: auto; border-bottom: 1px solid var(--line); scrollbar-width: none; }
.tabs::-webkit-scrollbar { display: none; }
.tab {
  appearance: none; border: 0; background: none; cursor: pointer; white-space: nowrap;
  display: inline-flex; align-items: center; gap: 8px; padding: 12px 14px; margin-bottom: -1px;
  border-bottom: 2px solid transparent; color: var(--text-2); font-size: 14.5px; font-weight: 500;
}
.tab .sym { font-size: 18px; line-height: 1; color: var(--text-3); }
.tab[aria-selected="true"] { color: var(--text); border-bottom-color: var(--text); }
.tab[aria-selected="true"] .sym { color: var(--text); }

/* ---------- 3D表示と説明 ---------- */
.stage { display: grid; grid-template-columns: minmax(0, 1fr) 340px; gap: 16px; align-items: start; }
@media (max-width: 920px) { .stage { grid-template-columns: minmax(0, 1fr); } }
.viewport {
  position: relative; max-width: 100%; aspect-ratio: 16 / 11; min-height: 340px;
  border: 1px solid var(--line); border-radius: 12px; overflow: hidden;
  background: radial-gradient(120% 90% at 50% 40%, #0B1226 0%, var(--bg) 70%);
}
@media (max-width: 920px) { .viewport { aspect-ratio: auto; height: min(66vh, 560px); } }
#gl { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.labels { position: absolute; inset: 0; overflow: hidden; pointer-events: none; }
.lbl {
  position: absolute; left: 0; top: 0; display: inline-flex; align-items: center; gap: 6px;
  padding: 3px 8px; border-radius: 999px; white-space: nowrap; will-change: transform;
  background: rgba(8, 12, 24, .74); border: 1px solid rgba(255, 255, 255, .08);
  font-size: 11.5px; line-height: 1.3; color: var(--text);
}
.lbl i { width: 7px; height: 7px; border-radius: 50%; flex: none; }
.lbl.muted { color: var(--text-3); background: rgba(8, 12, 24, .55); font-size: 11px; }
.lbl.plain { background: none; border: 0; padding: 0; }
.lbl.plain i { display: none; }
.hud {
  position: absolute; left: 10px; top: 10px; max-width: calc(100% - 20px); min-width: 196px;
  padding: 10px 12px; border-radius: 10px; pointer-events: none;
  background: rgba(8, 12, 24, .8); border: 1px solid var(--line); font-size: 12px; line-height: 1.6;
}
.hud:empty { display: none; }
.hud-title { margin-bottom: 2px; font-size: 11px; letter-spacing: .06em; color: var(--text-3); }
.hud-row { display: flex; justify-content: space-between; gap: 16px; }
.hud-row span { color: var(--text-3); }
.hud-row b { font: 500 12px/1.6 var(--font-mono); font-variant-numeric: tabular-nums; color: var(--text); }
.hud-row b.warn { color: var(--p-muon); }
.hud-eq { margin-top: 4px; font-size: 13px; }
.hud-eq b { font: 500 13px/1.6 var(--font-mono); color: var(--p-higgs); }
.hud-dim { color: var(--text-3); }
@media (max-width: 520px) { .hud { min-width: 0; padding: 8px 10px; font-size: 11px; } .hud-row b, .hud-eq b { font-size: 11px; } }
.hint { position: absolute; left: 12px; bottom: 14px; font-size: 11.5px; color: var(--text-3); pointer-events: none; }
@media (max-width: 520px) { .hint { display: none; } }
.playbar { position: absolute; right: 10px; bottom: 10px; display: flex; gap: 6px; }
.pbtn {
  appearance: none; cursor: pointer; padding: 9px 13px; border-radius: 8px;
  border: 1px solid var(--line-2); background: rgba(10, 15, 29, .88); color: var(--text); font-size: 13px; font-weight: 500;
}
.pbtn:hover { border-color: var(--accent); }
.fallback { position: absolute; inset: 0; display: grid; place-items: center; padding: 24px; text-align: center; color: var(--text-2); font-size: 14px; }

.panel { display: grid; gap: 14px; min-width: 0; padding: 16px 16px 18px; background: var(--bg-2); border: 1px solid var(--line); border-radius: 12px; }
.p-title { margin: 0; font: 700 22px/1.3 var(--font-display); }
.p-lead, .p-side { margin: 0; font-size: 13.5px; color: var(--text-2); }
.seg { display: flex; flex-wrap: wrap; gap: 6px; }
.seg-btn, .btn {
  appearance: none; cursor: pointer; padding: 8px 11px; border-radius: 8px;
  border: 1px solid var(--line-2); background: var(--bg-3); color: var(--text-2); font-size: 13px; font-weight: 500; line-height: 1.3;
}
.seg-btn:hover, .btn:hover { border-color: var(--accent); color: var(--text); }
.seg-btn[aria-pressed="true"] { background: var(--text); border-color: var(--text); color: var(--bg); }
.btn.ghost { background: none; }
.btn-row { display: flex; flex-wrap: wrap; gap: 6px; }
.steps { list-style: none; margin: 0; padding: 0; counter-reset: step; display: grid; gap: 7px; }
.steps li { counter-increment: step; position: relative; padding-left: 29px; font-size: 13.5px; color: var(--text-3); transition: color .2s; }
.steps li::before {
  content: counter(step); position: absolute; left: 0; top: 2px; width: 20px; height: 20px; border-radius: 50%;
  border: 1px solid var(--line-2); text-align: center; font: 500 11px/18px var(--font-mono); color: var(--text-3);
}
.steps li.on { color: var(--text); }
.steps li.on::before { background: var(--text); border-color: var(--text); color: var(--bg); }
.block { display: grid; gap: 8px; padding-top: 12px; border-top: 1px solid var(--line); }
.block h3 { margin: 0; font-size: 14px; font-weight: 700; }
.block p { margin: 0; font-size: 13px; color: var(--text-2); }
.block .cap { font-size: 12px; color: var(--text-3); }
.hist-wrap { position: relative; height: 150px; }
.hist-wrap canvas { width: 100%; height: 100%; display: block; }
.hist-meta { font-size: 13px; color: var(--text-2); }
.stat { font: 500 13px/1.5 var(--font-mono); font-variant-numeric: tabular-nums; color: var(--text); }
.badge { display: inline-block; margin-left: 6px; padding: 2px 7px; border-radius: 999px; background: rgba(255, 181, 71, .16); color: var(--p-higgs); font-size: 11.5px; }
.stat-line { margin: 0; font-size: 13px; color: var(--text-2); }
.legend { list-style: none; margin: 0; padding: 12px 0 0; border-top: 1px solid var(--line); display: flex; flex-wrap: wrap; gap: 6px 14px; font-size: 12px; color: var(--text-2); }
.legend li { display: inline-flex; align-items: center; gap: 6px; }
.legend i { width: 16px; height: 0; border-top: 3px solid var(--c); border-radius: 2px; }
.legend i.dash { border-top: 2px dashed var(--c); }
.legend i.dot { width: 9px; height: 9px; border: 0; border-radius: 50%; background: var(--c); }
.legend .legend-note { color: var(--text-3); }
.note { margin: 0; font-size: 12px; color: var(--text-3); }
.note b { color: var(--text-2); font-weight: 500; }
.life svg { width: 100%; height: auto; display: block; }
.life .t-tick { fill: var(--text-3); font: 400 10px var(--font-mono); }
.life .t-name { fill: var(--text-2); font: 500 11px var(--font-body); }
.life .t-val { fill: var(--text-3); font: 400 10px var(--font-mono); }
.facts { margin: 0; display: grid; gap: 4px; font-size: 12.5px; }
.facts div { display: grid; grid-template-columns: 6.5em minmax(0, 1fr); gap: 8px; }
.facts dt { color: var(--text-3); }
.facts dd { margin: 0; color: var(--text-2); }
.foot { margin-top: 22px; font-size: 12px; color: var(--text-3); }

@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; } }