/* === 基礎設定 === */
:root {
  --primary: #2563eb;
  --primary-light: #dbeafe;
  --success: #16a34a;
  --success-light: #dcfce7;
  --warning: #d97706;
  --warning-light: #fef3c7;
  --danger: #dc2626;
  --danger-light: #fee2e2;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-500: #6b7280;
  --gray-700: #374151;
  --gray-900: #111827;
  --radius: 8px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--gray-50);
  color: var(--gray-900);
  line-height: 1.5;
}

/* === 版面 === */
.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 20px;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  background: white;
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
}

header h1 {
  font-size: 18px;
  font-weight: 600;
}

header .user-info {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  color: var(--gray-500);
}

/* === 登入 === */
.auth-page {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 80vh;
}

.auth-card {
  background: white;
  border-radius: var(--radius);
  padding: 40px;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
  text-align: center;
}

.auth-card h2 { margin-bottom: 8px; }
.auth-card p { color: var(--gray-500); margin-bottom: 24px; font-size: 14px; }

.auth-card input[type="email"] {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 15px;
  margin-bottom: 12px;
}

.auth-card .auth-msg {
  margin-top: 12px;
  font-size: 14px;
  color: var(--success);
}

/* === 按鈕 === */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border: none;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.15s;
}
.btn:hover { opacity: 0.85; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary { background: var(--primary); color: white; }
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn-outline { background: white; border: 1px solid var(--gray-300); color: var(--gray-700); }
.btn-sm { padding: 4px 10px; font-size: 13px; }
.btn-logout { background: none; border: none; color: var(--gray-500); cursor: pointer; font-size: 13px; }
.btn-logout:hover { color: var(--danger); }

/* === Tab 導覽 === */
.tabs {
  display: flex;
  gap: 0;
  margin: 20px 0 0;
  border-bottom: 2px solid var(--gray-200);
}

.tab {
  padding: 10px 20px;
  border: none;
  background: none;
  font-size: 14px;
  font-weight: 500;
  color: var(--gray-500);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: all 0.15s;
}

.tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

/* === CSV 上傳 === */
.upload-zone {
  border: 2px dashed var(--gray-300);
  border-radius: var(--radius);
  padding: 40px;
  text-align: center;
  background: white;
  margin: 20px 0;
  cursor: pointer;
  transition: border-color 0.15s;
}

.upload-zone:hover,
.upload-zone.dragover {
  border-color: var(--primary);
  background: var(--primary-light);
}

.upload-zone p { color: var(--gray-500); font-size: 14px; }
.upload-zone .icon { font-size: 36px; margin-bottom: 8px; }

/* === 預覽卡片 === */
.preview-card {
  background: white;
  border-radius: var(--radius);
  padding: 20px;
  margin: 16px 0;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.preview-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
  margin-bottom: 16px;
}

.stat-item {
  text-align: center;
  padding: 12px;
  background: var(--gray-50);
  border-radius: var(--radius);
}

.stat-item .number {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
}

.stat-item .label {
  font-size: 12px;
  color: var(--gray-500);
  margin-top: 2px;
}

/* === 篩選列 === */
.filter-bar {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  margin: 16px 0;
}

.filter-bar select,
.filter-bar input {
  padding: 6px 10px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 13px;
  background: white;
}

.filter-bar .count {
  margin-left: auto;
  font-size: 13px;
  color: var(--gray-500);
}

/* === 支出列表 === */
.expense-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.expense-card {
  background: white;
  border-radius: var(--radius);
  border: 1px solid var(--gray-200);
  overflow: hidden;
}

.expense-header {
  display: grid;
  grid-template-columns: 1fr auto auto auto;
  gap: 12px;
  align-items: center;
  padding: 12px 16px;
  cursor: pointer;
  transition: background 0.1s;
}

.expense-header:hover { background: var(--gray-50); }

.expense-header .seller {
  font-weight: 500;
  font-size: 14px;
}

.expense-header .invoice-no {
  font-size: 12px;
  color: var(--gray-500);
}

.expense-header .date {
  font-size: 13px;
  color: var(--gray-500);
  white-space: nowrap;
}

.expense-header .amount {
  font-weight: 600;
  font-size: 15px;
  white-space: nowrap;
  min-width: 80px;
  text-align: right;
}

/* === Badge（狀態標籤） === */
.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 500;
  white-space: nowrap;
}

.badge-pending { background: var(--warning-light); color: var(--warning); }
.badge-approved { background: var(--success-light); color: var(--success); }
.badge-rejected { background: var(--danger-light); color: var(--danger); }
.badge-vat { background: var(--primary-light); color: var(--primary); }
.badge-income { background: #f3e8ff; color: #7c3aed; }
.badge-non { background: var(--gray-100); color: var(--gray-500); }
.badge-unknown { background: var(--warning-light); color: var(--warning); }

/* === 展開明細 === */
.expense-detail {
  display: none;
  padding: 0 16px 16px;
  border-top: 1px solid var(--gray-100);
}

.expense-detail.open { display: block; }

.items-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  margin-bottom: 12px;
}

.items-table th {
  text-align: left;
  padding: 6px 8px;
  color: var(--gray-500);
  font-weight: 500;
  border-bottom: 1px solid var(--gray-200);
}

.items-table td {
  padding: 6px 8px;
  border-bottom: 1px solid var(--gray-100);
}

.items-table .amount-col {
  text-align: right;
}

/* === 行內編輯 === */
.edit-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  padding-top: 8px;
}

.edit-row label {
  font-size: 12px;
  color: var(--gray-500);
}

.edit-row select,
.edit-row input {
  padding: 4px 8px;
  border: 1px solid var(--gray-300);
  border-radius: 4px;
  font-size: 13px;
}

.edit-row select { min-width: 120px; }
.edit-row input[type="text"] { flex: 1; min-width: 150px; }

/* === 通知 === */
.toast {
  position: fixed;
  bottom: 20px;
  right: 20px;
  padding: 12px 20px;
  border-radius: var(--radius);
  color: white;
  font-size: 14px;
  z-index: 999;
  animation: slideIn 0.3s;
}

.toast-success { background: var(--success); }
.toast-error { background: var(--danger); }

@keyframes slideIn {
  from { transform: translateX(100px); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* === 載入中 === */
.loading {
  text-align: center;
  padding: 40px;
  color: var(--gray-500);
}

.spinner {
  display: inline-block;
  width: 24px;
  height: 24px;
  border: 3px solid var(--gray-200);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

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

/* === 空狀態 === */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--gray-500);
}

.empty-state .icon { font-size: 48px; margin-bottom: 12px; }

/* === RWD === */
@media (max-width: 640px) {
  .expense-header {
    grid-template-columns: 1fr auto;
    gap: 8px;
  }
  .expense-header .date { grid-column: 1; }
  .expense-header .amount { grid-column: 2; grid-row: 1; }
  .edit-row { flex-direction: column; align-items: stretch; }
  .filter-bar { flex-direction: column; }
  .filter-bar .count { margin-left: 0; }
}