:root {
  --bg: #0f172a;
  --bg-elevated: #1e293b;
  --surface: #ffffff;
  --surface-muted: #f1f5f9;
  --text: #e2e8f0;
  --text-on-surface: #0f172a;
  --text-muted: #64748b;
  --accent: #38bdf8;
  --accent-strong: #0ea5e9;
  --border: #334155;
  --shadow: 0 6px 20px rgba(0, 0, 0, 0.35);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, sans-serif;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  min-height: 100dvh;
}

.app {
  max-width: 480px;
  margin: 0 auto;
  padding: env(safe-area-inset-top, 12px) 16px
    calc(env(safe-area-inset-bottom, 12px) + 16px);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.header h1 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 8px 0 0;
  letter-spacing: 0.02em;
  text-align: center;
  color: var(--text);
}

.controls {
  display: flex;
  flex-direction: column;
  gap: 12px;
  background: var(--bg-elevated);
  padding: 14px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 2;
}

.control-row {
  display: flex;
  gap: 8px;
  align-items: center;
}

.chip {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 8px;
  border-radius: 10px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease,
    color 0.15s ease;
  min-height: 44px;
}

.chip input[type="radio"] {
  position: absolute;
  opacity: 0;
  inset: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  cursor: pointer;
}

.chip:has(input:checked) {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--text-on-surface);
}

.chip--custom {
  padding: 4px;
}

.target-row .chip {
  font-size: 0.95rem;
  padding: 10px 4px;
}

.custom-input {
  width: 100%;
  background: transparent;
  border: none;
  color: inherit;
  font: inherit;
  text-align: center;
  padding: 8px 4px;
  outline: none;
  min-width: 0;
  appearance: textfield;
  -moz-appearance: textfield;
}

.custom-input::-webkit-outer-spin-button,
.custom-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.custom-input::placeholder {
  color: var(--text-muted);
}

.pages-row {
  flex-direction: column;
  align-items: stretch;
  gap: 6px;
}

.pages-label {
  font-size: 0.95rem;
  color: var(--text);
  display: flex;
  justify-content: space-between;
}

.pages-label output {
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  color: var(--accent);
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 36px;
  background: transparent;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-runnable-track {
  height: 6px;
  border-radius: 3px;
  background: var(--border);
}

input[type="range"]::-moz-range-track {
  height: 6px;
  border-radius: 3px;
  background: var(--border);
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg-elevated);
  margin-top: -10px;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

input[type="range"]::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg-elevated);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

.pages {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.page-card {
  background: var(--surface);
  color: var(--text-on-surface);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: grid;
  grid-template-columns: auto 1fr 1fr;
  gap: 8px 14px;
  align-items: center;
  box-shadow: var(--shadow);
  border: 2px solid transparent;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.page-card.is-half {
  padding: 8px 16px;
  background: var(--surface-muted);
}

.page-card.is-half .page-num::after {
  content: " ½";
  color: var(--text-muted);
  font-weight: 500;
}

.page-card.has-actual {
  border-color: var(--accent-strong);
}

.page-num {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-on-surface);
  min-width: 28px;
}

.page-field {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.page-field label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  font-weight: 600;
}

.remaining-value {
  font-size: 1.25rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text-on-surface);
}

.page-card.has-actual .remaining-value {
  color: var(--text-muted);
  text-decoration: line-through;
  font-weight: 500;
}

.actual-input {
  width: 100%;
  font-size: 1.15rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  padding: 6px 8px;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  background: #fff;
  color: var(--text-on-surface);
  min-width: 0;
  appearance: textfield;
  -moz-appearance: textfield;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.actual-input::-webkit-outer-spin-button,
.actual-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.actual-input:focus {
  border-color: var(--accent-strong);
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.2);
}

.footer {
  display: flex;
  justify-content: center;
  padding: 8px 0 4px;
}

.reset-btn {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  padding: 10px 18px;
  border-radius: 10px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
  min-height: 44px;
}

.reset-btn:hover,
.reset-btn:focus-visible {
  background: var(--bg-elevated);
  border-color: var(--accent);
  outline: none;
}