.expand-toggle {
    width: 18px;
    height: 18px;
    border: 2px solid #4f46e5; /* Indigo border */
    border-radius: 50%;
    display: inline-block;
    position: relative;
    cursor: pointer;
    transition: 0.2s ease;
}

    .expand-toggle::after {
        content: "";
        width: 8px;
        height: 8px;
        background: #4f46e5; /* Indigo fill */
        border-radius: 50%;
        position: absolute;
        top: 3px;
        left: 3px;
        opacity: 0;
        transition: opacity 0.2s ease;
    }

    /* When expanded (checked) */
    .expand-toggle.expanded::after {
        opacity: 1;
    }