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

body {
    font-family: system-ui, -apple-system, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.container {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    width: 100%;
    max-width: 500px;
}

h1 {
    margin-bottom: 1.5rem;
    color: #333;
}

#task-form {
display: flex;
gap: 0.5rem;
margin-bottom: 1.5rem;
}

#task-input {
flex: 1;
padding: 0.75rem;
border: 2px solid #e0e0e0;
border-radius: 0.5rem;
font-size: 1rem;
}

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

button {
    padding: 0.75rem 1.5rem;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
}

button:hover {
    background: #5568d3;
}

#task-list {
list-style: none;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem;
    background: #f8f9fa;
    border-radius: 0.5rem;
    margin-bottom: 0.5rem;
    transition: all 0.2s;
}

.task-item:hover {
    background: #e9ecef;
    transform: translateX(5px);
}

.task-item.completed {
    opacity: 0.6;
}

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

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

.task-text {
    flex: 1;
}

.task-delete {
    background: #dc3545;
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.task-delete:hover {
    background: #c82333;
}