/* ────────────────────────────────────────────
   リセット・ベース
──────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-primary:    #4a7fe8;
  --color-primary-bg: #eef3fd;
  --color-error:      #d94b3a;
  --color-error-bg:   #fdf1f0;
  --color-success:    #2a9e60;
  --color-border:     #e0e3ea;
  --color-text:       #1e2130;
  --color-text-sub:   #6b7182;
  --color-bg:         #f4f5f8;
  --color-card:       #ffffff;
  --radius-card:      14px;
  --radius-btn:       9px;
  --shadow-card:      0 2px 12px rgba(0, 0, 0, 0.07), 0 0 0 1px rgba(0,0,0,0.04);
  --font-sans:        'Hiragino Sans', 'Yu Gothic UI', 'Meiryo', sans-serif;
  --font-mono:        'Menlo', 'Consolas', 'Courier New', monospace;
  --transition:       0.18s ease;
}

html {
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.65;
  min-height: 100vh;
}

/* ────────────────────────────────────────────
   ヘッダー
──────────────────────────────────────────── */
.header {
  background: var(--color-card);
  border-bottom: 1px solid var(--color-border);
  padding: 20px 20px;
}

.header__inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 14px;
}

.header__icon {
  font-size: 1.8rem;
  line-height: 1;
  flex-shrink: 0;
}

.header__title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--color-text);
}

.header__desc {
  font-size: 0.8rem;
  color: var(--color-text-sub);
  margin-top: 1px;
}

/* ────────────────────────────────────────────
   メインレイアウト
──────────────────────────────────────────── */
.main {
  max-width: 800px;
  margin: 0 auto;
  padding: 28px 16px 60px;
}

/* ────────────────────────────────────────────
   カード
──────────────────────────────────────────── */
.card {
  background: var(--color-card);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
}

/* ────────────────────────────────────────────
   タブ
──────────────────────────────────────────── */
.tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.tab {
  padding: 9px 22px;
  border: 1.5px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-card);
  color: var(--color-text-sub);
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
}

.tab:hover:not(.tab--active) {
  border-color: #bbb;
  color: var(--color-text);
}

.tab--active {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-bg);
  font-weight: 700;
}

/* ────────────────────────────────────────────
   入力エリア
──────────────────────────────────────────── */
.input-area {
  padding: 24px;
  margin-bottom: 20px;
}

.color-inputs {
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  margin-bottom: 18px;
}

.color-input-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
  min-width: 200px;
  max-width: 260px;
}

.color-label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--color-text-sub);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.color-input-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* カラーピッカー */
.color-picker {
  width: 52px;
  height: 52px;
  border: 2px solid var(--color-border);
  border-radius: 10px;
  cursor: pointer;
  padding: 3px;
  background: transparent;
  flex-shrink: 0;
  transition: border-color var(--transition);
}

.color-picker:hover {
  border-color: #aab;
}

/* HEXテキスト入力 */
.hex-input {
  flex: 1;
  padding: 13px 14px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-btn);
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--color-text);
  background: #fafbfc;
  transition: border-color var(--transition), background var(--transition);
  letter-spacing: 0.05em;
}

.hex-input:focus {
  outline: none;
  border-color: var(--color-primary);
  background: #fff;
}

.hex-input.is-error {
  border-color: var(--color-error);
  background: var(--color-error-bg);
}

/* ────────────────────────────────────────────
   RGBスライダー
──────────────────────────────────────────── */
.rgb-sliders {
  margin-top: 4px;
}

.rgb-slider-row {
  display: flex;
  align-items: center;
  gap: 8px;
  height: 28px;
}

.rgb-slider-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  width: 16px;
  text-align: center;
  flex-shrink: 0;
}

.rgb-slider-label--r { color: #d94b3a; }
.rgb-slider-label--g { color: #2a9e60; }
.rgb-slider-label--b { color: #4a7fe8; }

.rgb-slider {
  flex: 1;
  height: 6px;
  -webkit-appearance: none;
  appearance: none;
  border-radius: 3px;
  outline: none;
  cursor: pointer;
}

.rgb-slider--r { background: linear-gradient(to right, #000, #ff0000); }
.rgb-slider--g { background: linear-gradient(to right, #000, #00cc55); }
.rgb-slider--b { background: linear-gradient(to right, #000, #4488ff); }

.rgb-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid var(--color-border);
  box-shadow: 0 1px 4px rgba(0,0,0,0.15);
  cursor: pointer;
  transition: border-color var(--transition);
}

.rgb-slider::-webkit-slider-thumb:hover {
  border-color: #999;
}

.rgb-slider::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #fff;
  border: 2px solid var(--color-border);
  box-shadow: 0 1px 4px rgba(0,0,0,0.15);
  cursor: pointer;
}

.rgb-slider-value {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-sub);
  width: 40px;
  text-align: right;
  flex-shrink: 0;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 2px 4px;
  background: #fafbfc;
  -moz-appearance: textfield;
}

.rgb-slider-value::-webkit-inner-spin-button,
.rgb-slider-value::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.rgb-slider-value:focus {
  outline: none;
  border-color: var(--color-primary);
  background: #fff;
}

/* ────────────────────────────────────────────
   エラーメッセージ
──────────────────────────────────────────── */
.error-msg {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-error);
  font-size: 0.85rem;
  padding: 10px 14px;
  background: var(--color-error-bg);
  border: 1px solid #f5c4be;
  border-radius: 8px;
  margin-bottom: 14px;
}

.error-msg::before {
  content: "⚠";
  font-size: 0.9rem;
  flex-shrink: 0;
}

/* ────────────────────────────────────────────
   生成ボタン
──────────────────────────────────────────── */
.generate-btn {
  width: 100%;
  padding: 15px;
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-btn);
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  box-shadow: 0 2px 8px rgba(74, 127, 232, 0.3);
}

.generate-btn:hover {
  background: #3a6bd4;
  box-shadow: 0 4px 14px rgba(74, 127, 232, 0.4);
}

.generate-btn:active {
  transform: translateY(1px);
  box-shadow: 0 1px 4px rgba(74, 127, 232, 0.3);
}

/* ────────────────────────────────────────────
   セクションタイトル
──────────────────────────────────────────── */
.section-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--color-text-sub);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

/* ────────────────────────────────────────────
   提案カード一覧
──────────────────────────────────────────── */
.results-area {
  margin-bottom: 24px;
}

.suggestions {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 12px;
}

/* ────────────────────────────────────────────
   提案グループ（パレットごと）
──────────────────────────────────────────── */
.suggestion-group {
  background: var(--color-card);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  padding: 14px 14px;
}

.suggestion-group__label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 3px;
}

.suggestion-group__reason {
  font-size: 0.75rem;
  color: var(--color-text-sub);
  margin-bottom: 10px;
  line-height: 1.45;
}

.suggestion-group__cards {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ────────────────────────────────────────────
   個別提案カード
──────────────────────────────────────────── */
.suggestion-card {
  background: #fafbfc;
  border-radius: 10px;
  border: 1.5px solid var(--color-border);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
  flex: 1;
  min-width: 140px;
}

.suggestion-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(0,0,0,0.08);
}

.suggestion-swatch {
  width: 100%;
  height: 56px;
}

.suggestion-info {
  padding: 10px 12px 12px;
}

.suggestion-hex-row {
  display: flex;
  align-items: center;
  gap: 6px;
}

.suggestion-hex {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: 0.03em;
}

.copy-btn {
  margin-left: auto;
  padding: 6px 12px;
  border: 1.5px solid var(--color-border);
  border-radius: 5px;
  background: #fff;
  font-family: var(--font-sans);
  font-size: 0.73rem;
  font-weight: 600;
  color: var(--color-text-sub);
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
  white-space: nowrap;
}

.copy-btn:hover {
  background: #f2f3f5;
  border-color: #bbb;
  color: var(--color-text);
}

.copy-btn.copied {
  border-color: var(--color-success);
  color: var(--color-success);
  background: #f0faf5;
}

/* ────────────────────────────────────────────
   プレビューエリア
──────────────────────────────────────────── */
.preview-area {
  margin-bottom: 20px;
}

.section-hint {
  font-size: 0.78rem;
  color: var(--color-text-sub);
  margin-top: -8px;
  margin-bottom: 14px;
}

.previews {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

/* ────────────────────────────────────────────
   プレビューカード
──────────────────────────────────────────── */
.preview-card {
  overflow: hidden;
}

.preview-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px 8px;
}

.preview-card__label {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--color-text);
}

.preview-card__rotate {
  width: 32px;
  height: 32px;
  border: 1.5px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  font-size: 1.1rem;
  line-height: 1;
  cursor: pointer;
  color: var(--color-text-sub);
  transition: border-color var(--transition), color var(--transition), background var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}

.preview-card__rotate:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-bg);
}

.preview-card__visual {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 16px 10px;
}

.preview-card__pie-wrap {
  flex-shrink: 0;
}

.preview-card__pie {
  display: block;
}

.preview-card__sample {
  flex: 1;
  padding: 14px 14px;
  border-radius: 8px;
  transition: background-color 0.25s ease;
  min-width: 0;
}

.preview-card__heading {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 6px;
  line-height: 1.4;
  transition: color 0.25s ease;
}

.preview-card__body {
  font-size: 0.78rem;
  line-height: 1.6;
  margin-bottom: 12px;
  transition: color 0.25s ease;
}

.preview-card__btn {
  padding: 7px 18px;
  border: none;
  border-radius: 5px;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  font-weight: 700;
  cursor: default;
  transition: background-color 0.25s ease, color 0.25s ease;
  box-shadow: 0 1px 4px rgba(0,0,0,0.12);
}

.preview-card__roles {
  display: flex;
  gap: 12px;
  padding: 10px 16px 14px;
  flex-wrap: wrap;
}

.preview-card__role {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.72rem;
  color: var(--color-text-sub);
}

.preview-card__role-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 1px solid rgba(0,0,0,0.1);
  flex-shrink: 0;
}

/* ────────────────────────────────────────────
   ユーティリティ
──────────────────────────────────────────── */
/* ────────────────────────────────────────────
   フッター
──────────────────────────────────────────── */
.footer {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px 16px;
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-text-sub);
}

.footer a {
  color: var(--color-text-sub);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

/* ────────────────────────────────────────────
   ユーティリティ
──────────────────────────────────────────── */
.hidden {
  display: none !important;
}

/* ────────────────────────────────────────────
   レスポンシブ（スマホ）
──────────────────────────────────────────── */
@media (max-width: 520px) {
  .header {
    padding: 16px;
  }

  .header__title {
    font-size: 1.05rem;
  }

  .main {
    padding: 20px 12px 48px;
  }

  .input-area {
    padding: 18px 16px;
  }

  .tabs {
    gap: 6px;
  }

  .tab {
    flex: 1;
    text-align: center;
    padding: 9px 12px;
  }

  .color-inputs {
    flex-direction: column;
    gap: 16px;
  }

  .color-input-group {
    min-width: unset;
  }

  .suggestions {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }

  .suggestion-group {
    padding: 12px 12px;
  }

  .previews {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .preview-card__visual {
    flex-direction: column;
    align-items: stretch;
    padding: 0 12px 8px;
  }

  .preview-card__pie-wrap {
    display: flex;
    justify-content: center;
  }

  .preview-card__sample {
    padding: 12px 10px;
  }
}

@media (max-width: 360px) {
  .suggestions {
    grid-template-columns: 1fr;
  }
}