:root {
  color-scheme: dark;
  --bg: #0B0D10;
  --surface: #15181D;
  --surface-2: #1C2026;
  --line: #262A31;
  --line-2: #2E333B;
  --text: #F3F5F7;
  --text-2: #C9CED4;
  --muted: #98A1AC;
  --dim: #3A404A;
  /* 教官画面：燃料の色（暗い背景用） */
  --regular: #FF5A5F;
  --diesel: #34D27B;
  /* グラフ用：色覚多様性に配慮して検証済み */
  --chart-regular: #F0563F;
  --chart-diesel: #169A73;
  --good: #0ca30c;
  --good-text: #3CC13C;
  --warning: #fab219;
  --critical: #E86A6A;
  --font: 'IBM Plex Sans JP', system-ui, sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, monospace;
}

* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font); -webkit-text-size-adjust: 100%; }
a { color: var(--text-2); }
a:hover { color: #fff; }
button { font-family: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible { outline: 2px solid var(--text); outline-offset: 2px; }
.mono { font-family: var(--mono); }
.num { font-variant-numeric: tabular-nums; }
.muted { color: var(--muted); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

@keyframes kfade { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }
@keyframes kscan { 0% { top: 18%; } 100% { top: 80%; } }
@keyframes kbreathe { 0%, 100% { transform: scale(1); } 50% { transform: scale(1.035); } }
@keyframes kpop { 0% { transform: scale(.5); opacity: 0; } 60% { transform: scale(1.1); opacity: 1; } 100% { transform: scale(1); } }
@keyframes kring { 0% { transform: scale(.85); opacity: .6; } 100% { transform: scale(1.7); opacity: 0; } }
@keyframes kdraw { from { stroke-dashoffset: 24; } to { stroke-dashoffset: 0; } }
@keyframes kup { from { opacity: 0; transform: translateY(28px); } to { opacity: 1; transform: none; } }
@keyframes kshake { 0%, 100% { transform: translateX(0); } 20% { transform: translateX(-9px); } 40% { transform: translateX(9px); } 60% { transform: translateX(-5px); } 80% { transform: translateX(5px); } }
@keyframes kblink { 0%, 49% { opacity: 1; } 50%, 100% { opacity: 0; } }
@keyframes kglow { 0%, 100% { box-shadow: 0 0 0 0 var(--glow); } 50% { box-shadow: 0 0 0 7px transparent; } }
@keyframes kalarm { 0%, 100% { box-shadow: 0 0 0 0 rgba(255,255,255,.45); } 50% { box-shadow: 0 0 0 16px rgba(255,255,255,0); } }
@keyframes kpulse { 0%, 100% { box-shadow: 0 0 0 0 rgba(250,178,25,.5); } 50% { box-shadow: 0 0 0 6px rgba(250,178,25,0); } }
@keyframes klive { 0%, 100% { opacity: 1; } 50% { opacity: .35; } }
@keyframes kspin { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }

.fade { animation: kfade .35s ease-out both; }
.spinner { width: 22px; height: 22px; border-radius: 999px; border: 3px solid var(--line-2); border-top-color: var(--text); animation: kspin .8s linear infinite; }

/* ボタン */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; height: 44px; padding: 0 16px; border-radius: 14px; border: 1px solid var(--line-2); background: var(--surface); color: var(--text); font-size: 14px; font-weight: 700; text-decoration: none; cursor: pointer; }
.btn:hover { background: var(--surface-2); color: var(--text); }
.btn-primary { background: var(--text); color: var(--bg); border-color: var(--text); }
.btn-primary:hover { background: #fff; color: var(--bg); }
.btn-ghost { background: transparent; }
.btn-danger { background: #D61F26; border-color: #D61F26; color: #fff; }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn-lg { height: 58px; border-radius: 18px; font-size: 18px; letter-spacing: .06em; }

.pill { display: inline-flex; align-items: center; gap: 6px; padding: 4px 12px; border-radius: 999px; font-size: 13px; font-weight: 700; white-space: nowrap; }
.dot { width: 9px; height: 9px; border-radius: 999px; flex: none; }

.card { background: var(--surface); border: 1px solid var(--line); border-radius: 22px; }

.input { height: 44px; padding: 0 12px; border-radius: 12px; border: 1px solid var(--line-2); background: var(--surface-2); color: var(--text); font-family: inherit; font-size: 15px; }
.field { display: flex; flex-direction: column; gap: 6px; font-size: 13px; color: var(--text-2); }

.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); z-index: 50; max-width: calc(100% - 32px); padding: 12px 18px; border-radius: 14px; background: var(--text); color: var(--bg); font-size: 14px; font-weight: 700; box-shadow: 0 10px 30px rgba(0,0,0,.45); animation: kfade .25s ease-out; }
.toast.error { background: #D61F26; color: #fff; }

/* 給油機QRを直接読んだときの案内 */
body.notice main { max-width: 460px; margin: 0 auto; padding: 64px 24px; display: flex; flex-direction: column; gap: 18px; line-height: 1.7; }
body.notice h1 { font-size: 24px; margin: 0; }
body.notice .btn { align-self: flex-start; }

dialog { border: 1px solid var(--line-2); border-radius: 22px; background: var(--surface); color: var(--text); padding: 24px; width: min(440px, calc(100% - 32px)); }
dialog::backdrop { background: rgba(0,0,0,.6); }