:root {
  --primary: #60a5fa;
  --primary-hover: #3b82f6;
  --secondary: #34d399;
  --secondary-hover: #10b981;
  --danger: #f87171;
  --danger-hover: #ef4444;
  --bg-color: #0f172a;
  --card-bg: rgba(30, 41, 59, 0.7);
  --input-bg: #1e293b;
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --border-color: #334155;
  --border-radius: 16px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -2px rgba(0, 0, 0, 0.5);
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, 'Helvetica Neue', 'Segoe UI', 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol', sans-serif;
  background-color: var(--bg-color);
  background-image: radial-gradient(at 0% 0%, rgba(59, 130, 246, 0.15) 0, transparent 50%),
    radial-gradient(at 50% 0%, rgba(16, 185, 129, 0.1) 0, transparent 50%);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
}

.container {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

/* Header */
.app-header {
  text-align: center;
  margin-bottom: 30px;
  padding-top: 20px;
}

.app-header h1 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 5px;
}

/* Card layout */
.card {
  background-color: var(--card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  padding: 30px;
  margin-bottom: 24px;
  transition: var(--transition);
}

/* Forms */
.form-group {
  margin-bottom: 24px;
}

.form-group label {
  display: block;
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 10px;
  color: var(--text-main);
}

.form-control {
  width: 100%;
  padding: 14px 18px;
  font-size: 1rem;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  background-color: var(--input-bg);
  color: var(--text-main);
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(96, 165, 250, 0.2);
  background-color: #242f44;
}

.form-control::placeholder {
  color: #64748b;
}

/* Print Header (평소엔 숨김) */
.print-header {
  display: none;
}

/* Print Optimizations (A4 1장 흑백 최적화) */
@media print {
  @page {
    size: A4 portrait;
    margin: 0;
    /* 브라우저 기본 주소/타이틀 마스킹 */
  }

  body {
    background: white !important;
    color: black !important;
    font-size: 9pt !important;
    margin: 0 !important;
    padding: 10mm 12mm !important;
    /* 페이지 마진을 패딩으로 확보 */
  }

  .print-header {
    display: block !important;
    text-align: center;
    font-size: 1.2rem;
    /* 축소하여 한 줄 유지 보장 */
    font-weight: 800;
    margin-bottom: 8px;
    border-bottom: 2px solid #000;
    padding-bottom: 6px;
    white-space: nowrap;
    /* 한 줄 유지 */
  }

  .cost-table th,
  .cost-table td {
    padding: 6px 8px !important;
    /* 14px에서 대폭 축소 */
    font-size: 8.5pt !important;
  }

  .app-header h2 {
    font-size: 1.8rem !important;
    /* 2.1에서 축소 */
  }

  * {
    color: black !important;
    box-shadow: none !important;
    text-shadow: none !important;
    background: transparent !important;
  }

  .container {
    width: 100% !important;
    max-width: none !important;
    padding: 0 !important;
    margin: 0 !important;
  }

  /* 화면 조작용 UI 요소 전부 숨김 */
  .btn,
  button,
  .app-header p:not(#authorInfo),
  .app-header h2+p:not(#authorInfo),
  footer,
  #btnSettings,
  .unit-toggle {
    display: none !important;
  }

  /* 테이블 인쇄 레이아웃 */
  .card {
    border: none !important;
    padding: 0 !important;
    margin: 0 !important;
  }

  .cost-table {
    width: 100% !important;
    border-collapse: collapse !important;
    font-size: 9pt !important;
  }

  .cost-table th,
  .cost-table td {
    border: 1px solid #000 !important;
    padding: 4px 8px !important;
    color: #000 !important;
  }

  .cost-table th {
    background-color: #f0f0f0 !important;
    -webkit-print-color-adjust: exact !important;
    print-color-adjust: exact !important;
  }

  .category-header {
    background-color: #e2e8f0 !important;
    -webkit-print-color-adjust: exact !important;
    print-color-adjust: exact !important;
    font-weight: bold;
  }

  .sub-total {
    background-color: #f8fafc !important;
    -webkit-print-color-adjust: exact !important;
    print-color-adjust: exact !important;
    font-weight: bold;
  }

  .grand-total-row {
    background-color: #f1f5f9 !important;
    -webkit-print-color-adjust: exact !important;
    print-color-adjust: exact !important;
    font-weight: bold;
    font-size: 11pt !important;
  }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  width: 100%;
}

.btn-primary {
  background-color: var(--primary);
  color: white;
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
}

.btn-secondary {
  background-color: var(--secondary);
  color: white;
}

.btn-secondary:hover {
  background-color: var(--secondary-hover);
}

.btn-danger {
  background-color: var(--danger);
  color: white;
  padding: 8px 16px;
  font-size: 0.9rem;
}

.btn-danger:hover {
  background-color: var(--danger-hover);
}

.btn-outline {
  background-color: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-main);
}

.btn-outline:hover {
  background-color: var(--bg-color);
}

/* Modal */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-content {
  background-color: #1e293b;
  border: 1px solid var(--border-color);
  border-radius: 24px;
  width: 90%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  padding: 32px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  transform: translateY(-20px);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-overlay.active .modal-content {
  transform: translateY(0);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 15px;
}

.close-btn {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-muted);
}

/* List Item Helpers */
.list-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 18px;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  margin-bottom: 12px;
  background-color: #242f44;
}

.list-item span {
  flex: 1;
  font-weight: 500;
  color: var(--text-main);
}

.list-item .btn-danger {
  margin-left: 15px;
  width: 80px;
  flex-shrink: 0;
}

/* Responsive Utilities */
@media (max-width: 600px) {
  .btn {
    padding: 10px 20px;
  }

  .card {
    padding: 20px;
  }
}