:root {
  --bg: #f5f5fb;
  --card-bg: #ffffff;
  --text-main: #222222;
  --text-sub: #555555;
  --accent: #4a90e2;
  --accent-soft: #e3f0ff;
  --danger: #d9534f;
  --border-soft: #e0e0ea;
  --shadow-soft: 0 8px 20px rgba(15, 23, 42, 0.08);
  --radius-card: 16px;
  --radius-pill: 999px;
  --transition-fast: 0.18s ease-out;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 16px;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Noto Sans JP",
    sans-serif;
  background: radial-gradient(circle at top, #eef3ff 0, #f9fafb 60%, #f3f4f6 100%);
  color: var(--text-main);
}

.page-wrapper {
  max-width: 720px;
  margin: 0 auto;
}

.page-header {
  text-align: center;
  margin-bottom: 16px;
}

.page-title {
  font-size: 1.3rem;
  margin: 0 0 4px;
}

.page-subtitle {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-sub);
}

.card {
  background-color: var(--card-bg);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-soft);
  padding: 16px 18px 18px;
  margin-bottom: 16px;
}

.card-title {
  margin: 0 0 12px;
  font-size: 1.05rem;
}

.field {
  margin-bottom: 12px;
}

.field label {
  display: block;
  font-size: 0.88rem;
  margin-bottom: 4px;
  color: var(--text-sub);
}

.required {
  color: var(--danger);
  font-size: 0.78rem;
  margin-left: 2px;
}

.optional {
  font-size: 0.78rem;
  color: var(--text-sub);
}

input[type="number"] {
  width: 100%;
  padding: 8px 10px;
  border-radius: 10px;
  border: 1px solid var(--border-soft);
  font-size: 1rem;
  outline: none;
  background-color: #fdfdff;
  transition: border-color var(--transition-fast),
    box-shadow var(--transition-fast), background-color var(--transition-fast);
}

input[type="number"]:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(74, 144, 226, 0.18);
  background-color: #ffffff;
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.primary-button,
.secondary-button,
.ghost-button {
  border-radius: 999px;
  padding: 10px 18px;
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform var(--transition-fast),
    box-shadow var(--transition-fast), background-color var(--transition-fast),
    color var(--transition-fast), border-color var(--transition-fast);
}

.primary-button {
  background: linear-gradient(135deg, #4a90e2, #2b65d9);
  color: #ffffff;
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.35);
}

.primary-button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.4);
}

.primary-button:active {
  transform: translateY(0);
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

.secondary-button {
  background-color: var(--accent-soft);
  color: var(--accent);
  border: 1px solid rgba(74, 144, 226, 0.4);
}

.secondary-button:hover {
  background-color: #d3e4ff;
}

.ghost-button {
  background-color: transparent;
  color: var(--text-sub);
  border: 1px solid var(--border-soft);
}

.ghost-button:hover {
  background-color: #f3f4f9;
}

.full-width {
  width: 100%;
}

.error-text {
  min-height: 1em;
  font-size: 0.8rem;
  color: var(--danger);
  margin: 2px 0 8px;
}

.summary-text {
  margin-top: 0;
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: var(--text-sub);
}

/* 運動カード */
.exercise-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.exercise-card {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid var(--border-soft);
  background-color: #fdfdff;
  cursor: pointer;
  transition: box-shadow var(--transition-fast),
    transform var(--transition-fast), border-color var(--transition-fast),
    background-color var(--transition-fast);
}

.exercise-card:hover {
  box-shadow: 0 6px 12px rgba(148, 163, 184, 0.35);
  transform: translateY(-1px);
  border-color: rgba(74, 144, 226, 0.6);
  background-color: #ffffff;
}

.exercise-icon {
  font-size: 1.4rem;
  margin-right: 10px;
}

.exercise-main {
  flex: 1;
}

.exercise-label {
  font-size: 0.9rem;
  color: var(--text-sub);
  margin-bottom: 2px;
}

.exercise-time {
  font-size: 1.1rem;
  font-weight: 600;
}

.exercise-meta {
  font-size: 0.75rem;
  color: #888888;
}

/* 注意書き・フッター */
.note {
  font-size: 0.78rem;
  color: var(--text-sub);
  margin: 4px 2px 20px;
}

.page-footer {
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-sub);
  margin-bottom: 8px;
}

.footer-text {
  margin: 0;
}

/* オーバーレイ・モーダル（チャレンジモード） */
.overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 999;
}

.overlay.hidden {
  display: none;
}

.overlay-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.4);
  backdrop-filter: blur(2px);
}

.modal {
  position: relative;
  z-index: 1;
  width: min(420px, 92vw);
  max-height: 90vh;
  background-color: #ffffff;
  border-radius: 20px;
  box-shadow: 0 18px 35px rgba(15, 23, 42, 0.45);
  padding: 16px 16px 18px;
  display: flex;
  flex-direction: column;
}

.modal-close {
  position: absolute;
  top: 8px;
  right: 10px;
  background: transparent;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  color: #999999;
}

.modal-header {
  display: flex;
  align-items: center;
  margin-bottom: 12px;
}

.challenge-icon {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background-color: var(--accent-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin-right: 8px;
}

.modal-header-text {
  flex: 1;
}

.modal-title {
  margin: 0;
  font-size: 1rem;
}

.modal-subtitle {
  margin: 2px 0 0;
  font-size: 0.8rem;
  color: var(--text-sub);
}

.modal-body {
  margin-top: 4px;
}

.hidden {
  display: none !important;
}

.ready-text {
  font-size: 0.95rem;
  margin-bottom: 10px;
}

/* タイマー表示 */
.timer-display {
  font-variant-numeric: tabular-nums;
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-align: center;
  margin-bottom: 6px;
}

.timer-target-text {
  font-size: 0.85rem;
  color: var(--text-sub);
  text-align: center;
  margin-bottom: 12px;
}

.progress-bar {
  width: 100%;
  height: 8px;
  border-radius: 999px;
  background: #eef0f7;
  overflow: hidden;
  margin-bottom: 8px;
}

.progress-inner {
  height: 100%;
  width: 0%;
  border-radius: inherit;
  background: linear-gradient(90deg, #4a90e2, #2ecc71);
  transition: width 0.3s ease-out;
}

.timer-message {
  font-size: 0.85rem;
  text-align: center;
  min-height: 1.2em;
  color: #16a34a;
  margin-bottom: 10px;
}

.timer-controls {
  display: flex;
  gap: 8px;
  justify-content: center;
}

/* 小さめ端末対応 */
@media (min-width: 640px) {
  .exercise-grid {
    grid-template-columns: 1fr 1fr;
  }
}