details {
    padding: 5px 10px;
    margin: 1rem 0;
}

summary {
    cursor: pointer;
    display: flex;
    align-items: center;
    list-style: none;
}

summary::before {
    content: "►";
    font-size: 22px;
    margin-right: 8px;
    transition: transform 0.2s ease;
}

details[open] summary::before {
    transform: rotate(90deg);
}