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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 2rem 1rem;
}

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

h1 {
    color: white;
    text-align: center;
    margin-bottom: 2rem;
    font-size: 2.5rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.card {
    background: white;
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.card h2 {
    color: #333;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card p {
    color: #666;
    margin-bottom: 1rem;
}

.button-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.btn-secondary {
    background: #6c757d;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-secondary:hover {
    background: #5a6268;
}

.btn-success {
    background: #28a745;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-success:hover:not(:disabled) {
    background: #218838;
}

.btn-success:disabled {
    background: #6c757d;
    cursor: not-allowed;
}

.import-area {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.file-name {
    color: #666;
    font-size: 0.9rem;
}

.preview-area {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 1rem;
    max-height: 300px;
    overflow-y: auto;
    font-family: monospace;
    font-size: 0.85rem;
}

.preview-placeholder {
    color: #999;
    text-align: center;
}

.status-area {
    background: #e3f2fd;
    border-radius: 8px;
    padding: 1rem;
    color: #1565c0;
}

.task-preview {
    border-bottom: 1px solid #ddd;
    padding: 0.5rem;
    display: flex;
    justify-content: space-between;
}

.task-preview.completed {
    text-decoration: line-through;
    color: #888;
}

.category-badge {
    background: #e9ecef;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.7rem;
}

.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 12px 20px;
    border-radius: 8px;
    color: white;
    font-size: 14px;
    z-index: 1000;
    animation: slideIn 0.3s ease;
}

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

@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .import-area {
        flex-direction: column;
        align-items: stretch;
    }
}