web/src-web/src/theme/theme-base/components/input/_togglebutton.scss
.p-togglebutton.p-button {
    background: $toggleButtonBg;
    border: $toggleButtonBorder;
    color: $toggleButtonTextColor;
    transition: $formElementTransition;

    .p-button-icon-left,
    .p-button-icon-right {
        color: $toggleButtonIconColor;
    }

    &:not(.p-disabled):not(.p-highlight):hover {
        background: $toggleButtonHoverBg;
        border-color: $toggleButtonHoverBorderColor;
        color: $toggleButtonTextHoverColor;

        .p-button-icon-left,
        .p-button-icon-right {
            color: $toggleButtonIconHoverColor;
        }
    }

    &.p-highlight {
        background: $toggleButtonActiveBg;
        border-color: $toggleButtonActiveBorderColor;
        color: $toggleButtonTextActiveColor;

        .p-button-icon-left,
        .p-button-icon-right {
            color: $toggleButtonIconActiveColor;
        }

        &:hover {
            background: $toggleButtonActiveHoverBg;
            border-color: $toggleButtonActiveHoverBorderColor;
            color: $toggleButtonTextActiveHoverColor;

            .p-button-icon-left,
            .p-button-icon-right {
                color: $toggleButtonIconActiveHoverColor;
            }
        }
    }
    
    &.p-invalid > .p-button {
        @include invalid-input();
    }
}