* {
    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: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
}

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

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

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

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
    margin-bottom: 25px;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.stat-card h3 {
    font-size: 2rem;
    color: #667eea;
    margin-bottom: 5px;
}

.stat-card p {
    color: #666;
    font-size: 0.9rem;
}

.add-task-section {
    background: white;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

#taskForm {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: 10px;
}

input, select {
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 5px;
    font-size: 1rem;
}

input:focus, select:focus {
    outline: none;
    border-color: #667eea;
}

.btn-add {
    background: #667eea;
    color: white;
    border: none;
    padding: 12px 25px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.btn-add:hover {
    background: #5568d3;
}

.filter-section {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.filter-btn {
    background: white;
    border: 2px solid white;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 0.95rem;
}

.filter-btn:hover {
    background: #f0f0f0;
}

.filter-btn.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

.tasks-section {
    background: white;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    min-height: 200px;
}

.tasks-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px;
    background: #f9f9f9;
    border-radius: 8px;
    border-left: 4px solid #667eea;
    transition: all 0.3s;
}

.task-item.completed {
    opacity: 0.6;
    background: #f0f0f0;
}

.task-item.completed .task-text {
    text-decoration: line-through;
}

.task-item.priority-high {
    border-left-color: #dc3545;
}

.task-item.priority-medium {
    border-left-color: #ffc107;
}

.task-item.priority-low {
    border-left-color: #28a745;
}

.task-checkbox {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.task-text {
    flex: 1;
    font-size: 1rem;
    color: #333;
}

.task-priority {
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 600;
}

.priority-high {
    background: #ffe0e0;
    color: #dc3545;
}

.priority-medium {
    background: #fff3cd;
    color: #856404;
}

.priority-low {
    background: #d4edda;
    color: #155724;
}

.task-delete {
    background: #dc3545;
    color: white;
    border: none;
    padding: 6px 12px;
    border-radius: 5px;
    cursor: pointer;
    transition: opacity 0.3s;
}

.task-delete:hover {
    opacity: 0.8;
}

.empty-state {
    text-align: center;
    padding: 40px;
    color: #999;
    font-size: 1.1rem;
}

.actions-section {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.btn-secondary, .btn-danger {
    padding: 12px 25px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.95rem;
    transition: opacity 0.3s;
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-danger {
    background: #dc3545;
    color: white;
}

.btn-secondary:hover, .btn-danger:hover {
    opacity: 0.8;
}

@media (max-width: 768px) {
    #taskForm {
        grid-template-columns: 1fr;
    }
    
    .task-item {
        flex-wrap: wrap;
    }
}