* {
    box-sizing: border-box;
}

:root {
    --primary: #b30000;
    --primary-dark: #8f0000;
}

body {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    background: linear-gradient(135deg, #f3f4f6, #e5e7eb);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Card */
.container {
    background: white;
    width: 500px;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

/* Title */
h1 {
    text-align: center;
    color: #7a2d2d;
    margin-bottom: 25px;
}

/* Input Group */
.input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

input[type="text"] {
    flex: 1;
    padding: 12px;
    border-radius: 8px;
    border: 1px solid #ccc;
    font-size: 15px;
}

input[type="text"]:focus {
    outline: none;
    border-color: var(--primary);
}

/* Button */
button {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 12px 18px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
}

button:hover {
    background-color: var(--primary-dark);
}

/* Table */
table {
    width: 100%;
    border-collapse: collapse;
}

th {
    background-color: var(--primary);
    color: white;
    padding: 10px;
    text-align: center;
}

td {
    padding: 12px;
    text-align: center;
    border-bottom: 1px solid #eee;
    transition: background-color 0.2s ease, transform 0.2s ease;
}

tbody tr:hover {
    background-color: #f9f9f9;
    transform: scale(1.01);
}

/* Completed Task */
.completed {
    text-decoration: line-through;
    color: gray;
}

/* Delete */
.delete {
    cursor: pointer;
    color: var(--primary);
    font-size: 18px;
    transition: transform 0.2s ease, color 0.2s ease;
}

.delete:hover {
    transform: scale(1.3);
    color: var(--primary-dark);
}

/* Checkbox */
input[type="checkbox"] {
    transform: scale(1.2);
    cursor: pointer;
}

/* Responsive */
@media (max-width: 600px) {
    .container {
        width: 90%;
    }

    table {
        font-size: 14px;
    }
}