:root {
  --bg: #f3f4f6;
  --card: #ffffff;
  --text: #111827;
  --muted: #6b7280;
  --line: #e5e7eb;
  --accent: #2563eb;
  --accent-text: #ffffff;
  --up: #15803d;
  --up-bg: #dcfce7;
  --down: #b91c1c;
  --down-bg: #fee2e2;
  --same-bg: #f3f4f6;
  --radius: 14px;
  --tabbar-h: 64px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0f17;
    --card: #161b26;
    --text: #f3f4f6;
    --muted: #9ca3af;
    --line: #273042;
    --accent: #3b82f6;
    --up: #4ade80;
    --up-bg: #14361f;
    --down: #f87171;
    --down-bg: #3b1515;
    --same-bg: #1f2633;
  }
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, sans-serif;
  font-size: 17px;
  line-height: 1.4;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
}

button, input, select { font: inherit; color: inherit; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 5;
  background: var(--bg);
  padding: calc(env(safe-area-inset-top) + 10px) 16px 8px;
}

.topbar h1 { margin: 0 auto; max-width: 608px; font-size: 30px; font-weight: 800; letter-spacing: -0.02em; }

main {
  padding: 4px 16px calc(var(--tabbar-h) + env(safe-area-inset-bottom) + 24px);
  max-width: 640px;
  margin: 0 auto;
  outline: none;
}

.tabbar {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  z-index: 10;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--card);
  border-top: 1px solid var(--line);
  padding-bottom: env(safe-area-inset-bottom);
}

.tabbar button {
  height: var(--tabbar-h);
  border: 0;
  background: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  cursor: pointer;
}

.tabbar button span { font-size: 22px; line-height: 1; }
.tabbar button[aria-current="page"] { color: var(--accent); }

.card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 16px;
  margin: 12px 0;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.06);
}

.card h2 { margin: 0; font-size: 21px; font-weight: 750; overflow-wrap: anywhere; }
.card-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 8px; }

.muted { color: var(--muted); }
.small { font-size: 14px; }

.date-row { display: flex; align-items: center; gap: 8px; margin: 4px 0 8px; }
.date-row label { font-weight: 600; color: var(--muted); }
.date-row input[type="date"] {
  flex: 1;
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--card);
  padding: 8px 12px;
  font-weight: 600;
}

.last-time {
  margin: 10px 0 0;
  padding: 10px 12px;
  background: var(--same-bg);
  border-radius: 10px;
  font-size: 15px;
}
.last-time strong { display: block; font-size: 13px; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); }
.goal { margin-top: 6px; font-weight: 600; }

.sets { list-style: none; margin: 12px 0 0; padding: 0; }
.sets li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 0;
  border-top: 1px solid var(--line);
}
.sets .num { width: 28px; color: var(--muted); font-weight: 700; }
.sets .val { flex: 1; font-size: 20px; font-weight: 700; font-variant-numeric: tabular-nums; }

.badge {
  font-size: 13px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 999px;
  white-space: nowrap;
  background: var(--same-bg);
  color: var(--muted);
}
.badge.up { background: var(--up-bg); color: var(--up); }
.badge.down { background: var(--down-bg); color: var(--down); }

.icon-btn {
  border: 0;
  background: none;
  color: var(--muted);
  font-size: 20px;
  min-width: 44px;
  min-height: 44px;
  border-radius: 10px;
  cursor: pointer;
}
.icon-btn:active { background: var(--same-bg); }

.set-form {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 8px;
  margin-top: 12px;
  align-items: end;
}
.set-form label { display: block; font-size: 13px; font-weight: 600; color: var(--muted); margin-bottom: 4px; }
.set-form input {
  width: 100%;
  min-height: 52px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  padding: 8px 6px;
  font-size: 22px;
  font-weight: 700;
  text-align: center;
  font-variant-numeric: tabular-nums;
}
.set-form input:focus, .date-row input:focus, #add-name:focus {
  outline: 3px solid rgba(37, 99, 235, 0.35);
  border-color: var(--accent);
}

.form-error { color: var(--down); font-size: 14px; margin: 6px 0 0; }
.form-error:empty { display: none; }

.btn {
  min-height: 52px;
  border: 0;
  border-radius: 12px;
  padding: 0 18px;
  font-weight: 700;
  cursor: pointer;
}
.btn.primary { background: var(--accent); color: var(--accent-text); }
.btn.ghost { background: var(--same-bg); }
.btn.danger { background: var(--down-bg); color: var(--down); }
.btn.block { width: 100%; display: block; margin: 12px 0; font-size: 18px; }
.btn:active { transform: scale(0.98); }

.empty { text-align: center; padding: 28px 12px; }
.empty .big { font-size: 44px; }
.empty p { margin: 8px 0; }

.list-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  text-align: left;
  border: 0;
  cursor: pointer;
}
.list-btn .title { font-size: 19px; font-weight: 700; overflow-wrap: anywhere; }
.list-btn .chev { color: var(--muted); font-size: 22px; }

.back { border: 0; background: none; color: var(--accent); font-weight: 600; padding: 8px 0; min-height: 44px; cursor: pointer; }

.chart-wrap { margin-top: 8px; }
.chart-wrap svg { width: 100%; height: auto; display: block; }
.chart-wrap .axis { stroke: var(--line); stroke-width: 1; }
.chart-wrap .line { fill: none; stroke: var(--accent); stroke-width: 3; stroke-linejoin: round; stroke-linecap: round; }
.chart-wrap .dot { fill: var(--accent); }
.chart-wrap text { fill: var(--muted); font-size: 12px; }

.stats { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 12px; }
.stat { background: var(--same-bg); border-radius: 10px; padding: 10px 12px; }
.stat .k { font-size: 13px; color: var(--muted); font-weight: 600; }
.stat .v { font-size: 20px; font-weight: 800; font-variant-numeric: tabular-nums; }

.session { padding: 10px 0; border-top: 1px solid var(--line); }
.session:first-of-type { border-top: 0; }
.session .d { display: flex; justify-content: space-between; gap: 8px; font-weight: 700; }
.session .s { font-variant-numeric: tabular-nums; margin-top: 2px; }

.seg { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; background: var(--same-bg); padding: 4px; border-radius: 12px; margin-top: 10px; }
.seg button { min-height: 44px; border: 0; border-radius: 9px; background: none; font-weight: 700; cursor: pointer; }
.seg button[aria-pressed="true"] { background: var(--card); box-shadow: 0 1px 2px rgba(0, 0, 0, 0.15); }

dialog {
  border: 0;
  border-radius: 18px;
  padding: 20px;
  width: min(92vw, 460px);
  background: var(--card);
  color: var(--text);
}
dialog::backdrop { background: rgba(0, 0, 0, 0.45); }
dialog h2 { margin: 0 0 12px; }
.label { display: block; font-size: 14px; font-weight: 600; color: var(--muted); margin-bottom: 6px; }
#add-name {
  width: 100%;
  min-height: 52px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  padding: 8px 12px;
  font-size: 19px;
}
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0 4px; }
.chips:empty { display: none; }
.chips button {
  border: 1px solid var(--line);
  background: var(--bg);
  border-radius: 999px;
  padding: 8px 14px;
  min-height: 40px;
  font-weight: 600;
  cursor: pointer;
}
.row { display: flex; gap: 8px; justify-content: flex-end; margin-top: 16px; }
.row .btn { flex: 1; }

#toast {
  position: fixed;
  left: 50%;
  bottom: calc(var(--tabbar-h) + env(safe-area-inset-bottom) + 16px);
  transform: translateX(-50%);
  background: var(--text);
  color: var(--bg);
  padding: 10px 16px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
  z-index: 20;
  max-width: 90vw;
  text-align: center;
}
#toast.show { opacity: 1; }

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