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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    backdrop-filter: blur(10px);
}

.header {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
    padding: 30px;
    text-align: center;
    position: relative;
}

.header-icon {
    font-size: 48px;
    margin-bottom: 10px;
    filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.2));
}

.header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0 0 10px 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.header p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin: 0;
}

.upload-section {
    padding: 40px;
}

.input-group {
    margin-bottom: 30px;
}

.input-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 12px;
    color: #374151;
    font-size: 1.1rem;
}

#csvInput {
    width: 100%;
    padding: 20px;
    border: 2px solid #e5e7eb;
    border-radius: 12px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 14px;
    line-height: 1.5;
    resize: vertical;
    background: #f9fafb;
    transition: all 0.3s ease;
}

#csvInput:focus {
    outline: none;
    border-color: #6366f1;
    background: white;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.input-info {
    margin-top: 8px;
}

.input-info small {
    color: #6b7280;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 4px;
}

.button-group {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 15px 30px;
    border: none;
    border-radius: 12px;
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

.btn:before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.btn:hover:before {
    left: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(16, 185, 129, 0.4);
}

.btn-secondary {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(245, 158, 11, 0.3);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(245, 158, 11, 0.4);
}

.btn-info {
    background: linear-gradient(135deg, #06b6d4 0%, #0891b2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(6, 182, 212, 0.3);
}

.btn-info:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(6, 182, 212, 0.4);
}

.btn-purple {
    background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-purple:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(139, 92, 246, 0.4);
}

.btn-orange {
    background: linear-gradient(135deg, #f97316 0%, #ea580c 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(249, 115, 22, 0.3);
}

.btn-orange:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(249, 115, 22, 0.4);
}

.options-section {
    padding: 0 40px 40px;
}

.section-title {
    font-size: 1.8rem;
    margin-bottom: 25px;
    color: #374151;
    display: flex;
    align-items: center;
    gap: 12px;
}

.option-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.option-card {
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
    border: 2px solid #e2e8f0;
    border-radius: 16px;
    padding: 25px;
    text-align: center;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.option-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border-color: #6366f1;
}

.option-card h3 {
    color: #1e293b;
    margin-bottom: 10px;
    font-size: 1.3rem;
}

.option-card p {
    color: #64748b;
    margin-bottom: 20px;
    line-height: 1.5;
}

.data-preview {
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 20px;
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 12px;
    color: #374151;
    text-align: left;
    min-height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.export-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 25px;
    flex-wrap: wrap;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

.btn-icon {
    font-size: 18px;
}

.error-message.success {
    background: linear-gradient(135deg, #f0fdf4 0%, #dcfce7 100%);
    border-color: #86efac;
    color: #15803d;
}

.error-message.info {
    background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
    border-color: #93c5fd;
    color: #1d4ed8;
}

.error-message.warning {
    background: linear-gradient(135deg, #fffbeb 0%, #fef3c7 100%);
    border-color: #fbbf24;
    color: #b45309;
}

.error-message {
    margin: 20px 40px;
    padding: 20px;
    background: linear-gradient(135deg, #fef2f2 0%, #fee2e2 100%);
    border: 1px solid #fecaca;
    border-radius: 12px;
    color: #dc2626;
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 500;
}

.results-section {
    padding: 0 40px 40px;
}

.results-title {
    font-size: 1.8rem;
    margin-bottom: 25px;
    color: #374151;
    display: flex;
    align-items: center;
    gap: 12px;
}

.table-container {
    overflow-x: auto;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    background: white;
}

#resultsTable {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

#resultsTable th {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
    padding: 20px 16px;
    text-align: left;
    font-weight: 600;
    font-size: 15px;
    position: sticky;
    top: 0;
    z-index: 10;
}

#resultsTable td {
    padding: 16px;
    border-bottom: 1px solid #f3f4f6;
    vertical-align: top;
}

#resultsTable tbody tr {
    transition: background-color 0.2s ease;
}

#resultsTable tbody tr:hover {
    background-color: #f8fafc;
}

#resultsTable tbody tr:nth-child(even) {
    background-color: #fafbfc;
}

#resultsTable tbody tr:nth-child(even):hover {
    background-color: #f1f5f9;
}

.status-badge {
    display: inline-block;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-add {
    background: linear-gradient(135deg, #dcfdf7 0%, #a7f3d0 100%);
    color: #065f46;
    border: 1px solid #6ee7b7;
}

.status-modify {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    color: #92400e;
    border: 1px solid #f59e0b;
}

.status-delete {
    background: linear-gradient(135deg, #fee2e2 0%, #fecaca 100%);
    color: #991b1b;
    border: 1px solid #f87171;
}

.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px;
    color: #6b7280;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f4f6;
    border-top: 4px solid #6366f1;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading p {
    font-size: 16px;
    font-weight: 500;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    .container {
        margin: 10px;
        border-radius: 15px;
    }
    
    .header {
        padding: 20px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .upload-section, .results-section {
        padding: 20px;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .btn {
        justify-content: center;
    }
    
    #resultsTable {
        font-size: 12px;
    }
    
    #resultsTable th,
    #resultsTable td {
        padding: 12px 8px;
    }
}

/* 스크롤바 스타일링 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f5f9;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
}