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

body {
    font-family: Arial, sans-serif;
    background-color: #f0f4f8;
    display: flex;
    justify-content: center;
    padding: 40px 20px;
}

.container {
    background-color: #fff;
    border-radius: 12px;
    padding: 30px;
    width: 100%;
    max-width: 500px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    margin-bottom: 24px;
    color: #2d3748;
}

.input-area {
    display: flex;
    gap: 10px;
    margin-bottom: 24px;
}

input {
    flex: 1;
    padding: 10px 14px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 16px;
    outline: none;
}

input:focus {
    border-color: #667eea;
}

button {
    padding: 10px 18px;
    background-color: #667eea;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    cursor: pointer;
}

button:hover {
    background-color: #5a67d8;
}

ul {
    list-style: none;
}

li {
    display:flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 14px;
    margin-bottom: 10px;
    background-color: #f7fafc;
    border-radius: 8px;
    border: 4px solid #667eea;
}

li.completed span{
    text-decoration: line-through;
    color: #a0aec0;
}

li span {
    cursor: pointer;
    font-size: 16px;
    flex: 1;
}

.delete-btn {
    background-color: #fc8181;
    padding: 6px 12px;
    font-size: 14px;
    border-radius: 6px;

}
.delete-btn:hover {
    background-color: #f56565;
}