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

body {
    min-height: 100vh;
    background: #f5f5f5;
    display: flex;
    justify-content: center;
    align-items: center;
}

.app {
    width: 90%;
    max-width: 420px;
    background: white;
    padding: 25px;
    border-radius: 16px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 5px;
}

.subtitle {
    text-align: center;
    color: #777;
    margin-bottom: 20px;
}

.input-box {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

input {
    flex: 1;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    outline: none;
}

input:focus {
    border-color: #246fe0;
}

button {
    padding: 12px 16px;
    border: none;
    background: #246fe0;
    color: white;
    border-radius: 8px;
    cursor: pointer;
}

button:hover {
    background: #1e5bb8;
}

ul {
    list-style: none;
}

li {
    background: white;
    padding: 12px;
    margin-bottom: 10px;
    border-radius: 8px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 1px solid #e0e0e0;
}

li.completed span {
    text-decoration: line-through;
    color: #777;
}

.task-text {
    cursor: pointer;
}

.delete-btn {
    background: #ef4444;
    padding: 7px 10px;
    font-size: 12px;
}

.delete-btn:hover {
    background: #b91c1c;
}