:root {
    --input-padding-x: .5rem;
    --input-padding-y: .75rem;
}

.form-label-group {
    position: relative;
    margin-bottom: 1rem;
}

.form-label-group > input,
.form-label-group > select,
.form-label-group > label {
    padding: var(--input-padding-y) var(--input-padding-x);
}

.form-label-group > label {
    position: absolute;
    top: 0;
    left: 12px;
    display: block;
    margin-bottom: 0; /* Override default `<label>` margin */
    line-height: 1.5;
    color: #495057;
    border: 1px solid transparent;
    border-radius: .25rem;
    transition: all .1s ease-in-out;
}
/*
.form-label-group input::-webkit-input-placeholder,
.form-label-group select::-webkit-input-placeholder {
    color: transparent;
}

.form-label-group input:-ms-input-placeholder,
.form-label-group select:-ms-input-placeholder {
    color: transparent;
}

.form-label-group input::-ms-input-placeholder,
.form-label-group select::-ms-input-placeholder {
    color: transparent;
}

.form-label-group input::-moz-placeholder,
.form-label-group select::-moz-placeholder {
    color: transparent;
}

.form-label-group input::placeholder,
.form-label-group select::placeholder {
    color: transparent;
}
*/
.form-label-group input,
.form-label-group select {
    padding-top: calc(var(--input-padding-y) + var(--input-padding-y) * (2 / 3));
    padding-bottom: calc(var(--input-padding-y) / 3);
}

.form-label-group input ~ label,
.form-label-group select ~ label {
    padding-top: calc(var(--input-padding-y) / 3);
    padding-bottom: calc(var(--input-padding-y) / 3);
    font-size: 12px;
    color: #777;
}