* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, sans-serif;
}

body {
    background: linear-gradient(120deg, #6a11cb, #2575fc);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container {
    background: #fff;
    padding: 25px;
    width: 350px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

h1 {
    text-align: center;
    margin-bottom: 15px;
}

.input-box {
    display: flex;
    gap: 10px;
}

input {
    flex: 1;
    padding: 8px;
    border-radius: 5px;
    border: 1px solid #ccc;
}

button {
    padding: 8px 15px;
    background: #2575fc;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

button:hover {
    background: #1b5fd8;
}

ul {
    list-style: none;
    margin-top: 15px;
}

li {
    background: #f2f2f2;
    padding: 8px;
    border-radius: 5px;
    margin-bottom: 8px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.completed {
    text-decoration: line-through;
    color: gray;
    opacity: 0.7;
}

.delete-btn {
    background: red;
    color: white;
    border: none;
    padding: 5px 8px;
    border-radius: 4px;
    cursor: pointer;
}