mdb-ui-kit/less/_checkboxes.less

.form-horizontal .checkbox {
    padding-top: 20px;
}
.checkbox {
    label {
        padding-left: 10px;
        cursor: pointer;
        position: relative;
        span {
            display: block;
            position: absolute;
            left: 0px;
            transition-duration: 0.2s;
        }
        .check {
            display: inline-block;
            width: 20px;
            height: 20px;
            border: 2px solid;
            border-radius: 2px;
            overflow: hidden;
            position: relative;
            top: 5px;
            left: -3px;
        }
        .check:after {
            display: block;
            position: absolute;
            content: "";
            background-color: @lightbg-text;
            left: -5px;
            top: -15px;
            height: 50px;
            width: 50px;
            border-radius: 100%;
            z-index: 1;
            opacity: 0;
            margin: 0;
        }
        .check:before {
            position: absolute;
            content: "";
            transform: rotate(45deg);
            display: block;
            margin-top: -4px;
            margin-left: 6px;
            width: 0;
            height: 0;
            box-shadow:
                0 0 0 0,
                0 0 0 0,
                0 0 0 0,
                0 0 0 0,
                0 0 0 0,
                0 0 0 0,
                0px 0px 0 0px inset;
            animation: checkbox-off 0.3s linear forwards;
        }
    }


    // Hide native checkbox
    input[type=checkbox] { opacity: 0; }


    input[type=checkbox]:focus ~ .check:after {
        opacity: 0.2;
    }

    input[type=checkbox]:checked ~ .check {
    }
    input[type=checkbox]:checked ~ .check:before {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            20px -12px 0 11px;
        animation: checkbox-on 0.3s linear forwards;
    }

    // Ripple effect on click
    input[type=checkbox]:not(:checked) ~ .check:after {
        animation: rippleOff 500ms linear forwards;
    }
    input[type=checkbox]:checked ~ .check:after {
        animation: rippleOn 500ms linear forwards;
    }

    // Make animate quickly when not hover
    &:not(:hover) input[type=checkbox] ~ .check {
        &:before, &:after {
            animation-duration: 1ms;
        }
    }

    // Style for disabled inputs
    input[type=checkbox][disabled]:not(:checked) ~ .check:before {
        opacity: 0.5;
    }
    input[type=checkbox][disabled] ~ .check:after {
        background-color: @lightbg-text;
        transform: rotate(-45deg);
    }

    .variations(~" input[type=checkbox]:checked ~ .check:after", background-color, @success);
    .variations(~" input[type=checkbox]:checked ~ .check:before", color, #4caf50);
    .variations(~" input[type=checkbox]:checked ~ .check", color, #4caf50);
}


@keyframes checkbox-on {
    0% {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            15px 2px 0 11px;
    }
    50% {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            20px 2px 0 11px;
    }
    100% {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            20px -12px 0 11px;
    }
}
@keyframes checkbox-off {
    0% {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            20px -12px 0 11px,
            0 0 0 0 inset;
    }

    25% {
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            20px -12px 0 11px,
            0 0 0 0 inset;
    }
    50% {
        transform: rotate(45deg);
        margin-top: -4px;
        margin-left: 6px;
        width: 0px;
        height: 0px;
        box-shadow:
            0 0 0 10px,
            10px -10px 0 10px,
            32px 0px 0 20px,
            0px 32px 0 20px,
            -5px 5px 0 10px,
            15px 2px 0 11px,
            0 0 0 0 inset;
    }
    51% {
        transform: rotate(0deg);
        margin-top: -2px;
        margin-left: -2px;
        width: 20px;
        height: 20px;
        box-shadow:
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0px 0px 0 10px inset;
    }
    100% {
        transform: rotate(0deg);
        margin-top: -2px;
        margin-left: -2px;
        width: 20px;
        height: 20px;
        box-shadow:
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0 0 0 0,
            0px 0px 0 0px inset;
    }
}