/* ========================================
   common.css - 共通ベーススタイル
   ======================================== */

/* リセットCSS */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul, ol {
  list-style: none;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
  border: none;
  background: none;
}

button {
  cursor: pointer;
}

table {
  border-collapse: collapse;
}

/* ========================================
   レスポンシブ基盤
   ======================================== */

/* コンテナ */
.container {
  width: 100%;
  max-width: 480px;
  margin: 0 auto;
  padding: 0 16px;
}

/* ========================================
   共通レイアウト
   ======================================== */

/* ヘッダー */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 12px 0;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-logo {
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1.3;
}

.site-logo a {
  display: block;
}

/* ナビゲーション */
.site-nav ul {
  display: flex;
  gap: 16px;
}

.site-nav a {
  font-size: 0.85rem;
  padding: 4px 0;
}

/* メインコンテンツ */
.main-content {
  flex: 1;
  padding: 24px 0 40px;
}

/* フッター */
.site-footer {
  padding: 24px 0;
  text-align: center;
  font-size: 0.75rem;
  line-height: 1.8;
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 4px 12px;
  margin-top: 8px;
}

.footer-links a {
  padding: 4px 0;
}

.footer-links .separator {
  opacity: 0.4;
}

.footer-special {
  margin-top: 8px;
}

.footer-special a {
  padding: 4px 0;
}

/* ========================================
   共通コンポーネント
   ======================================== */

/* カードグリッド */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

/* カード */
.card {
  overflow: hidden;
}

.card-image {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.card-body {
  padding: 12px 16px;
}

.card-title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.card-meta {
  font-size: 0.8rem;
  margin-bottom: 8px;
  opacity: 0.7;
}

.card-text {
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ボタン共通 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  min-width: 44px;
  padding: 10px 24px;
  font-size: 0.9rem;
  font-weight: 600;
  text-align: center;
  transition: opacity 0.2s, transform 0.1s;
}

.btn:active {
  transform: scale(0.97);
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-block {
  display: flex;
  width: 100%;
}

.btn-sm {
  min-height: 36px;
  padding: 6px 16px;
  font-size: 0.8rem;
}

.btn-lg {
  min-height: 52px;
  padding: 14px 32px;
  font-size: 1rem;
}

/* フォーム共通 */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.form-label .required {
  color: #e74c3c;
  margin-left: 4px;
  font-size: 0.75rem;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 8px;
  background: #fff;
  transition: border-color 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: #999;
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-radio-group,
.form-checkbox-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-radio-group label,
.form-checkbox-group label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.9rem;
  min-height: 44px;
  padding: 4px 0;
}

.form-radio-group input,
.form-checkbox-group input {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

/* ページタイトル */
.page-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.page-subtitle {
  font-size: 0.9rem;
  opacity: 0.7;
  margin-top: -12px;
  margin-bottom: 20px;
}

/* セクション */
.section {
  margin-bottom: 32px;
}

.section-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 12px;
}

/* アラートボックス */
.alert {
  padding: 14px 16px;
  border-radius: 8px;
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ========================================
   ユーティリティ
   ======================================== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.hidden { display: none !important; }

/* ========================================
   レスポンシブ
   ======================================== */
@media (min-width: 481px) {
  .container {
    max-width: 640px;
  }

  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}