* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    min-height: 100vh;
    background: #f5f7fa;
    color: #333;
    padding: 20px;
}

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

header {
    text-align: center;
    margin-bottom: 30px;
}

h1 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.subtitle {
    font-size: 1rem;
    color: #7f8c8d;
    margin-bottom: 1.5rem;
}

.card {
    background: white;
    border-radius: 10px;
    padding: 25px;
    width: 100%;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.upload-area {
    border: 2px dashed #bdc3c7;
    border-radius: 8px;
    padding: 30px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 20px;
}

.upload-area:hover {
    border-color: #3498db;
    background: #f8fafc;
}

.upload-icon {
    font-size: 2.5rem;
    margin-bottom: 10px;
    color: #3498db;
}

.upload-text {
    margin-bottom: 5px;
    color: #2c3e50;
    font-size: 1.1rem;
}

.upload-hint {
    font-size: 0.9rem;
    color: #7f8c8d;
}

#fileInput {
    display: none;
}

.options-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-bottom: 20px;
}

.option-group {
    margin-bottom: 0;
}

.option-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #2c3e50;
    font-size: 0.9rem;
}

.option-control {
    width: 100%;
    padding: 10px;
    border-radius: 6px;
    border: 1px solid #ddd;
    background: white;
    font-size: 0.9rem;
}

.option-control:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

.preview-container {
    margin: 20px 0;
    border: 1px solid #ddd;
    border-radius: 6px;
    padding: 15px;
}

.preview-title {
    margin-bottom: 15px;
    color: #2c3e50;
}

.sheet-tabs {
    display: flex;
    gap: 5px;
    margin-bottom: 15px;
    flex-wrap: wrap;
}

.sheet-tab {
    padding: 5px 15px;
    background: #ecf0f1;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
}

.sheet-tab.active {
    background: #3498db;
    color: white;
}

.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
}

th, td {
    border: 1px solid #ddd;
    padding: 8px;
    text-align: left;
}

th {
    background-color: #f2f2f2;
    font-weight: 600;
}

.btn {
    padding: 10px 20px;
    border-radius: 6px;
    border: none;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: #3498db;
    color: white;
}

.btn-primary:hover {
    background: #2980b9;
}

.btn-secondary {
    background: #ecf0f1;
    color: #2c3e50;
}

.btn-secondary:hover {
    background: #d5dbdb;
}

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

.btn-group {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.status {
    margin-top: 15px;
    padding: 12px;
    border-radius: 6px;
    text-align: center;
    display: none;
    font-size: 0.9rem;
}

.status.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
    display: block;
}

.status.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
    display: block;
}

.loading {
    text-align: center;
    margin: 15px 0;
}

.spinner {
    width: 30px;
    height: 30px;
    margin: 0 auto 10px;
    border: 3px solid rgba(52, 152, 219, 0.2);
    border-radius: 50%;
    border-top-color: #3498db;
    animation: spin 1s ease-in-out infinite;
}

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

@media (max-width: 600px) {
    .options-grid {
        grid-template-columns: 1fr;
    }
    
    .btn-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}
/* Previous styles remain the same, add these new styles */

.excel-logo {
    width: 60px;
    height: 60px;
    margin-bottom: 15px;
}

.upload-area {
    /* Add these to existing upload-area styles */
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 200px;
}

/* Add this to ensure table headers are visible in PDF */
th {
    background-color: #f2f2f2 !important;
    color: #000 !important;
    font-weight: bold !important;
}