* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #f0f4f8;
  color: #1a202c;
  min-height: 100vh;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 16px;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: #1e3a5f;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 3px solid #2563eb;
}

h2 {
  font-size: 1rem;
  font-weight: 600;
  color: #2d3748;
  margin-bottom: 12px;
}

/* フォーム */
.form-section {
  background: #fff;
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.form-group.full-width {
  grid-column: 1 / -1;
}

label {
  font-size: 0.8rem;
  font-weight: 600;
  color: #4a5568;
}

input[type="text"],
input[type="date"] {
  padding: 9px 12px;
  border: 1px solid #cbd5e0;
  border-radius: 6px;
  font-size: 0.95rem;
  color: #1a202c;
  background: #f7fafc;
  transition: border-color 0.2s;
}

input[type="text"]:focus,
input[type="date"]:focus {
  outline: none;
  border-color: #2563eb;
  background: #fff;
}

/* ボタン */
.btn {
  padding: 10px 24px;
  border: none;
  border-radius: 6px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}

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

.btn-primary {
  background: #2563eb;
  color: #fff;
}

.btn-primary:hover {
  background: #1d4ed8;
}

.btn-returned {
  background: #e2e8f0;
  color: #4a5568;
  font-size: 0.8rem;
  padding: 6px 12px;
}

.btn-returned:hover {
  background: #cbd5e0;
}

.btn-delete {
  background: #fee2e2;
  color: #c53030;
  font-size: 0.8rem;
  padding: 6px 12px;
}

.btn-delete:hover {
  background: #fecaca;
}

/* フィルター */
.filter-section {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 7px 18px;
  border: 2px solid #cbd5e0;
  border-radius: 20px;
  background: #fff;
  color: #4a5568;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.filter-btn.active {
  border-color: #2563eb;
  background: #2563eb;
  color: #fff;
}

.count-badge {
  font-size: 0.85rem;
  color: #718096;
  margin-left: auto;
}

/* 一覧 */
.list-section {
  background: #fff;
  border-radius: 10px;
  padding: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
  min-height: 80px;
}

.item-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.item-card {
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  padding: 14px 16px;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 8px;
  transition: background 0.2s;
}

.item-card.overdue {
  background: #fff5f5;
  border-color: #fc8181;
}

.item-card.returned {
  background: #f0fff4;
  border-color: #68d391;
  opacity: 0.75;
}

.item-info {
  flex: 1;
  min-width: 200px;
}

.item-name {
  font-size: 1rem;
  font-weight: 700;
  color: #1a202c;
  margin-bottom: 4px;
}

.item-borrower {
  font-size: 0.88rem;
  color: #4a5568;
  margin-bottom: 6px;
}

.item-dates {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.82rem;
  color: #718096;
}

.date-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

.overdue-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: #c53030;
  background: #fed7d7;
  padding: 2px 8px;
  border-radius: 10px;
  margin-left: 6px;
}

.returned-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: #276749;
  background: #c6f6d5;
  padding: 2px 8px;
  border-radius: 10px;
  margin-left: 6px;
}

.item-memo {
  font-size: 0.82rem;
  color: #718096;
  margin-top: 4px;
  font-style: italic;
}

.item-actions {
  display: flex;
  gap: 6px;
  align-items: center;
  margin-top: 4px;
}

.empty-msg {
  text-align: center;
  color: #a0aec0;
  font-size: 0.9rem;
  padding: 24px 0;
  display: none;
}

/* レスポンシブ */
@media (max-width: 520px) {
  .form-grid {
    grid-template-columns: 1fr;
  }

  .form-group.full-width {
    grid-column: 1;
  }

  h1 {
    font-size: 1.2rem;
  }

  .item-card {
    flex-direction: column;
  }

  .item-actions {
    width: 100%;
    justify-content: flex-end;
  }
}