:root {
  --bg: #ffffff;
  --fg: #000000;
  --muted: #707070;
  --faint: #9a9a9a;
  --line: rgba(0, 0, 0, 0.14);
  --hair: rgba(0, 0, 0, 0.08);
  --field-bg: #f4f4f4;
  --accent-line: rgba(0, 0, 0, 0.32);
  --t1: var(--fg);
  --t2: rgba(0, 0, 0, 0.55);
  --t3: rgba(0, 0, 0, 0.28);
  --max: 680px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --fg: #ffffff;
    --muted: #8c8c8c;
    --faint: #686868;
    --line: rgba(255, 255, 255, 0.16);
    --hair: rgba(255, 255, 255, 0.09);
    --field-bg: #151515;
    --accent-line: rgba(255, 255, 255, 0.36);
    --t1: var(--fg);
    --t2: rgba(255, 255, 255, 0.6);
    --t3: rgba(255, 255, 255, 0.3);
  }
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Helvetica Neue", system-ui, sans-serif;
  font-feature-settings: "tnum" 1, "cv01" 1;
  line-height: 1.4;
  -webkit-font-smoothing: antialiased;
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}

.app {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 22px 40px;
}

/* ---------- Header ---------- */
.head { margin-bottom: 30px; }

.head-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
}

h1 {
  font-size: clamp(1.9rem, 7vw, 2.7rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 0.98;
}

.sub {
  color: var(--muted);
  font-size: 0.8rem;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  letter-spacing: 0.01em;
}

/* ---------- Period toggle ---------- */
.period {
  display: inline-flex;
  border: 1px solid var(--accent-line);
  border-radius: 999px;
  overflow: hidden;
  flex: none;
}

.period-btn {
  appearance: none;
  border: 0;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 7px 13px;
  cursor: pointer;
}

.period-btn.is-active {
  background: var(--fg);
  color: var(--bg);
}

/* ---------- Inputs ---------- */
.inputs {
  display: grid;
  gap: 14px;
  margin-bottom: 34px;
}

@media (min-width: 600px) {
  .inputs { grid-template-columns: 1fr 1fr; }
}

.field {
  display: block;
  background: var(--field-bg);
  border-radius: 16px;
  padding: 16px 18px;
}

.field-label {
  display: block;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.field-note {
  display: block;
  color: var(--faint);
  font-size: 0.72rem;
  margin-top: 3px;
}

.input-wrap {
  display: flex;
  align-items: baseline;
  margin-top: 12px;
  border-bottom: 1px solid var(--accent-line);
  padding-bottom: 6px;
}

.prefix {
  font-size: 1.4rem;
  font-weight: 500;
  color: var(--faint);
  margin-right: 6px;
}

.input-wrap input {
  flex: 1;
  width: 100%;
  min-width: 0;
  border: 0;
  background: transparent;
  color: var(--fg);
  font: inherit;
  font-size: 1.9rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  outline: none;
}

.field-unit {
  display: block;
  margin-top: 7px;
  color: var(--faint);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ---------- Blocks ---------- */
.block {
  border-top: 1.5px solid var(--fg);
  padding: 14px 0 20px;
}

.block-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 10px;
}

.idx {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--faint);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
}

.block-head h2 {
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.head-num {
  margin-left: auto;
  font-size: 1rem;
  font-weight: 700;
}

/* ---------- Rows ---------- */
.row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 8px 0;
  font-size: 0.95rem;
  border-bottom: 1px solid var(--hair);
}

.row:last-of-type { border-bottom: 0; }

.row-key { display: inline-flex; align-items: baseline; gap: 9px; }

.row em {
  font-style: normal;
  color: var(--faint);
  font-size: 0.84em;
}

.num { font-variant-numeric: tabular-nums; white-space: nowrap; }

.row.hero {
  padding: 4px 0 16px;
  border-bottom: 0;
  align-items: baseline;
}

.hero-num {
  font-size: clamp(2rem, 9vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
}

.row.buffer {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  border-bottom: 0;
  font-weight: 600;
}

/* ---------- Meta grid (secondary data) ---------- */
.meta-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--hair);
  border: 1px solid var(--hair);
  border-radius: 12px;
  overflow: hidden;
}

.meta {
  background: var(--bg);
  padding: 11px 13px;
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.meta-label {
  color: var(--faint);
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.meta-val {
  font-size: 0.95rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

.dest {
  color: var(--muted);
  font-size: 0.76rem;
  margin-top: 10px;
  font-style: italic;
}

/* ---------- Proportion bar ---------- */
.bar {
  display: flex;
  height: 10px;
  border-radius: 999px;
  overflow: hidden;
  margin: 4px 0 14px;
  gap: 2px;
}

.seg { display: block; height: 100%; }
.seg[data-t="1"] { background: var(--t1); }
.seg[data-t="2"] { background: var(--t2); }
.seg[data-t="3"] { background: var(--t3); }

.dot {
  width: 8px;
  height: 8px;
  border-radius: 2px;
  flex: none;
  align-self: center;
}
.dot[data-t="1"] { background: var(--t1); }
.dot[data-t="2"] { background: var(--t2); }
.dot[data-t="3"] { background: var(--t3); }

/* ---------- Footer ---------- */
.foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 26px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  color: var(--faint);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.reset {
  appearance: none;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 6px 12px;
  border-radius: 999px;
  cursor: pointer;
}
.reset:active { background: var(--field-bg); }