/* =========================================================
   書籍管理 — ログインページ スタイルシート
   テーマ: 古書店の温かみ × 整然とした書棚（style.css と統一）
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+JP:wght@400;500;700&family=Shippori+Mincho:wght@400;600;800&family=DM+Mono:wght@400;500&display=swap');

/* --- CSS変数（style.css / bookshelf.css と共通） --- */
:root {
  --wood-dark:    #3d2b1f;
  --wood-mid:     #6b4226;
  --wood-light:   #a0632a;
  --wood-pale:    #d4a96a;
  --cream:        #fdf6ec;
  --parchment:    #f2e8d5;
  --ink:          #1c1209;
  --ink-muted:    #5a4030;
  --gold:         #c8973a;
  --gold-light:   #e8c97a;
  --error:        #c0392b;
  --error-bg:     rgba(192, 57, 43, 0.12);
  --success:      #27704a;
  --success-bg:   rgba(39, 112, 74, 0.12);

  --font-display: 'Shippori Mincho', 'Noto Serif JP', serif;
  --font-body:    'Noto Serif JP', serif;
  --font-mono:    'DM Mono', monospace;

  --radius-card:  6px;
  --radius-input: 4px;
  --transition:   0.2s ease;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--wood-dark);
  background-image:
    repeating-linear-gradient(
      92deg,
      transparent,
      transparent 60px,
      rgba(255,255,255,0.015) 60px,
      rgba(255,255,255,0.015) 61px
    ),
    repeating-linear-gradient(
      88deg,
      transparent,
      transparent 100px,
      rgba(0,0,0,0.04) 100px,
      rgba(0,0,0,0.04) 102px
    ),
    linear-gradient(
      180deg,
      #2a1d13 0%,
      #3d2b1f 20%,
      #4a3425 60%,
      #3d2b1f 100%
    );
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  color: var(--ink);
}

/* =========================================================
   ヘッダー
   ========================================================= */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 0 2.5rem;
  height: 64px;
  display: flex;
  align-items: center;
  background: linear-gradient(
    180deg,
    rgba(25, 14, 7, 0.97) 0%,
    rgba(35, 20, 10, 0.93) 100%
  );
  border-bottom: 2px solid var(--wood-light);
  box-shadow:
    0 2px 12px rgba(0,0,0,0.5),
    0 1px 0 var(--gold) inset;
  backdrop-filter: blur(6px);
}

.site-title {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--gold-light);
  letter-spacing: 0.08em;
  text-shadow: 0 1px 6px rgba(200, 151, 58, 0.4);
  -webkit-text-stroke: 0.5px rgba(200, 151, 58, 0.3);
}

.site-title::before {
  content: '📚 ';
  font-size: 1.2rem;
  vertical-align: middle;
  margin-right: 0.2rem;
}

/* =========================================================
   メインエリア（カードを上下中央に）
   ========================================================= */
main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 3rem 1.5rem;
}

/* =========================================================
   ログインカード
   ========================================================= */
.card {
  width: 100%;
  max-width: 400px;
  background-image:
    radial-gradient(
      ellipse at 20% 30%,
      rgba(255,255,255,0.25) 0%,
      transparent 60%
    ),
    linear-gradient(
      160deg,
      var(--parchment) 0%,
      #ede0c8 100%
    );
  border-radius: var(--radius-card);
  padding: 2.4rem 2.4rem 2.8rem;
  box-shadow:
    0 4px 0 #2a1a0e,
    0 10px 40px rgba(0,0,0,0.55),
    0 1px 0 rgba(255,255,255,0.6) inset;
  position: relative;
  overflow: hidden;
  animation: cardIn 0.4s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

@keyframes cardIn {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0);    }
}

/* カード上部の金ライン */
.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(
    90deg,
    transparent 0%,
    var(--gold) 20%,
    var(--gold-light) 50%,
    var(--gold) 80%,
    transparent 100%
  );
}

/* カードの装飾的な透かし文字 */
.card::after {
  content: '本棚';
  position: absolute;
  bottom: -0.6rem;
  right: 1.2rem;
  font-family: var(--font-display);
  font-size: 5rem;
  font-weight: 800;
  color: rgba(107, 66, 38, 0.07);
  pointer-events: none;
  line-height: 1;
  letter-spacing: 0.05em;
  user-select: none;
}

.card-label {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: 0.1em;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid rgba(107, 66, 38, 0.2);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card-label::before {
  content: '🔐';
  font-size: 1rem;
}

/* =========================================================
   インプットグループ
   ========================================================= */
.input-group {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  margin-bottom: 1.2rem;
}

.input-group label {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--ink-muted);
  letter-spacing: 0.06em;
}

.input-wrapper {
  position: relative;
}

.input-icon {
  position: absolute;
  left: 11px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.9rem;
  pointer-events: none;
  line-height: 1;
}

.input-wrapper input {
  width: 100%;
  padding: 0.72rem 0.9rem 0.72rem 2.2rem;
  font-family: var(--font-body);
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  color: var(--ink);
  background: rgba(255,255,255,0.65);
  border: 1.5px solid rgba(107, 66, 38, 0.35);
  border-radius: var(--radius-input);
  outline: none;
  transition:
    border-color var(--transition),
    box-shadow var(--transition),
    background var(--transition);
}

/* PIN入力はモノスペース */
#pin-input {
  font-family: var(--font-mono);
  letter-spacing: 0.2em;
}

.input-wrapper input::placeholder {
  color: rgba(90, 64, 48, 0.38);
  letter-spacing: 0.04em;
}

.input-wrapper input:hover {
  border-color: var(--wood-light);
  background: rgba(255,255,255,0.8);
}

.input-wrapper input:focus {
  border-color: var(--gold);
  background: #fff;
  box-shadow:
    0 0 0 3px rgba(200, 151, 58, 0.18),
    0 2px 8px rgba(0,0,0,0.08);
}

/* =========================================================
   メッセージ表示
   ========================================================= */
#message {
  margin-top: 0.2rem;
  margin-bottom: 0.8rem;
  padding: 0;
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.03em;
  border-radius: var(--radius-input);
  transition: all var(--transition);
  min-height: 0;
}

#message:not(:empty) {
  padding: 0.65rem 1rem;
}

#message.error {
  color: var(--error);
  background: var(--error-bg);
  border: 1px solid rgba(192, 57, 43, 0.25);
}

#message.success {
  color: var(--success);
  background: var(--success-bg);
  border: 1px solid rgba(39, 112, 74, 0.25);
}

/* =========================================================
   ログインボタン
   ========================================================= */
.btn-submit {
  width: 100%;
  margin-top: 0.6rem;
  padding: 0.85rem 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-size: 0.98rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--cream);
  background: linear-gradient(
    160deg,
    var(--wood-light) 0%,
    var(--wood-mid) 100%
  );
  border: none;
  border-radius: var(--radius-input);
  cursor: pointer;
  position: relative;
  overflow: hidden;
  box-shadow:
    0 3px 0 #3a1e0a,
    0 5px 14px rgba(0,0,0,0.28);
  transition:
    transform var(--transition),
    box-shadow var(--transition),
    filter var(--transition);
}

.btn-submit::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(255,255,255,0.12) 0%,
    transparent 60%
  );
  pointer-events: none;
}

.btn-submit:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow:
    0 5px 0 #3a1e0a,
    0 8px 20px rgba(0,0,0,0.32);
  filter: brightness(1.08);
}

.btn-submit:active:not(:disabled) {
  transform: translateY(1px);
  box-shadow:
    0 2px 0 #3a1e0a,
    0 3px 8px rgba(0,0,0,0.22);
}

.btn-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* スピナー */
.spinner {
  display: none;
  width: 16px;
  height: 16px;
  border: 2.5px solid rgba(255,255,255,0.35);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  flex-shrink: 0;
}

.btn-submit.loading .btn-text { opacity: 0.75; }
.btn-submit.loading .spinner  { display: block; }

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* =========================================================
   フッター
   ========================================================= */
footer {
  text-align: center;
  padding: 1.2rem;
  font-size: 0.7rem;
  color: rgba(212, 169, 106, 0.35);
  letter-spacing: 0.1em;
  border-top: 1px solid rgba(107, 66, 38, 0.25);
}

/* =========================================================
   レスポンシブ
   ========================================================= */
@media (max-width: 480px) {
  header {
    padding: 0 1.2rem;
    height: 56px;
  }

  .site-title { font-size: 1.3rem; }

  main { padding: 2rem 1rem; }

  .card {
    padding: 1.8rem 1.4rem 2.2rem;
  }
}

/* =========================================================
   アクセシビリティ: モーション軽減
   ========================================================= */
@media (prefers-reduced-motion: reduce) {
  .card         { animation: none; }
  .spinner      { animation: none; border-top-color: rgba(255,255,255,0.6); }
  .btn-submit   { transition: none; }
  .input-wrapper input { transition: none; }
}

/* =========================================================
   スクロールバー（WebKit）
   ========================================================= */
::-webkit-scrollbar       { width: 8px; }
::-webkit-scrollbar-track { background: var(--wood-dark); }
::-webkit-scrollbar-thumb { background: var(--wood-mid); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--wood-light); }