:root {
  --bg: #f5f3ef;
  --card-bg: #ffffff;
  --primary: #3367d6;
  --text-main: #222222;
  --text-sub: #666666;
  --border-light: #dddddd;
  --danger: #c62828;
  --radius-lg: 16px;
  --shadow-soft: 0 8px 20px rgba(0, 0, 0, 0.06);
}

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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Noto Sans JP", system-ui,
    sans-serif;
  background: var(--bg);
  color: var(--text-main);
  line-height: 1.6;
}

.page-header {
  padding: 16px 16px 8px;
}

.page-header h1 {
  margin: 0 0 4px;
  font-size: 1.4rem;
}

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

.container {
  padding: 8px 16px 24px;
  max-width: 640px;
  margin: 0 auto;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  padding: 16px 16px 20px;
  margin-bottom: 16px;
}

.card-title {
  margin: 0 0 12px;
  font-size: 1.1rem;
}

.form-group {
  margin-bottom: 12px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.inline-input {
  display: flex;
  align-items: center;
  gap: 4px;
}

.inline-input input {
  flex: 1;
}

input[type="number"],
select {
  width: 100%;
  padding: 8px 10px;
  border-radius: 8px;
  border: 1px solid var(--border-light);
  font-size: 1rem;
  font-family: inherit;
}

input[type="number"]:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px rgba(51, 103, 214, 0.2);
}

.suffix {
  font-size: 0.9rem;
  color: var(--text-sub);
}

.radio-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 0.9rem;
}

.radio-group label {
  font-weight: 400;
}

.radio-group input {
  margin-right: 4px;
}

.hint {
  margin: 4px 0 0;
  font-size: 0.8rem;
  color: var(--text-sub);
}

.details {
  margin-top: 4px;
  font-size: 0.9rem;
}

details summary {
  cursor: pointer;
  list-style: none;
}

details summary::-webkit-details-marker {
  display: none;
}

details summary::before {
  content: "▼ ";
  font-size: 0.7rem;
}

details[open] summary::before {
  content: "▲ ";
}

.details .form-group {
  margin-top: 8px;
}

.form-actions {
  margin-top: 14px;
  display: flex;
  justify-content: center;
}

button#calcButton {
  padding: 10px 20px;
  border-radius: 999px;
  border: none;
  background: var(--primary);
  color: #ffffff;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
}

button#calcButton:active {
  transform: translateY(1px);
}

.error-message {
  margin-top: 8px;
  font-size: 0.85rem;
  color: var(--danger);
  min-height: 1.2em;
}

.hidden {
  display: none;
}

/* 結果カード */

.card-result .result-main {
  margin-bottom: 12px;
}

.result-range {
  font-size: 1.2rem;
  font-weight: 700;
}

.result-range span.unit {
  font-size: 0.95rem;
  font-weight: 500;
}

.result-center {
  font-size: 0.9rem;
  color: var(--text-sub);
}

.result-meta {
  font-size: 0.85rem;
  color: var(--text-sub);
  margin-top: 4px;
}

/* 帯グラフ */

.range-wrapper {
  margin: 10px 0 6px;
}

.range-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-sub);
}

.range-bar {
  position: relative;
  margin-top: 4px;
  height: 10px;
  border-radius: 999px;
  background: #e0e7ff;
  overflow: hidden;
}

.range-bar-inner {
  position: absolute;
  inset: 0;
  background: #c3d4ff;
}

.range-marker {
  position: absolute;
  top: 50%;
  width: 0;
  height: 18px;
  border-left: 2px solid #1a3fb3;
  transform: translate(-1px, -50%);
}

.range-marker-label {
  margin-top: 4px;
  font-size: 0.8rem;
  color: var(--text-sub);
}

/* 注意書き */

.card-note {
  font-size: 0.85rem;
}

.note-list {
  padding-left: 1.1em;
  margin: 0;
}

.note-list li + li {
  margin-top: 4px;
}

/* PC での中央寄せ */

@media (min-width: 720px) {
  .page-header,
  .container {
    padding-left: 24px;
    padding-right: 24px;
  }

  .page-header,
  .container {
    max-width: 720px;
    margin: 0 auto;
  }
}