AdminLTE/build/scss/_forms.scss

/*
 * Component: Form
 * ---------------
 */
.form-group {
  &.has-icon {
    position: relative;
    .form-control {
      padding-right: 35px;
    }
    .form-icon {
      cursor: pointer;
      position: absolute;
      right: 3px;
      top: 0;
      padding: $input-btn-padding-y $input-btn-padding-x;
      // margin-top: -3px;
      border: 0;
      background-color: transparent;
      font-size: 1rem;
    }
  }
}

/* button groups */
.btn-group-vertical {
  .btn {
    &.btn-flat:first-of-type, &.btn-flat:last-of-type {
      @include border-radius(0);
    }
  }
}

/* Support Font Awesome icons in form-control */
.form-control-feedback {
  &.fa, 
  &.fas, 
  &.far, 
  &.fab {
    line-height: $input-height;
  }
}

.input-lg + .form-control-feedback.fa,
.input-group-lg + .form-control-feedback.fa,
.form-group-lg .form-control + .form-control-feedback.fa,
.input-lg + .form-control-feedback.fas,
.input-group-lg + .form-control-feedback.fas,
.form-group-lg .form-control + .form-control-feedback.fas,
.input-lg + .form-control-feedback.far,
.input-group-lg + .form-control-feedback.far,
.form-group-lg .form-control + .form-control-feedback.far,
.input-lg + .form-control-feedback.fab,
.input-group-lg + .form-control-feedback.fab,
.form-group-lg .form-control + .form-control-feedback.fab {
  line-height: $input-height-lg;
}

.input-sm + .form-control-feedback.fa,
.input-group-sm + .form-control-feedback.fa,
.form-group-sm .form-control + .form-control-feedback.fa,
.input-sm + .form-control-feedback.fas,
.input-group-sm + .form-control-feedback.fas,
.form-group-sm .form-control + .form-control-feedback.fas,
.input-sm + .form-control-feedback.far,
.input-group-sm + .form-control-feedback.far,
.form-group-sm .form-control + .form-control-feedback.far,
.input-sm + .form-control-feedback.fab,
.input-group-sm + .form-control-feedback.fab,
.form-group-sm .form-control + .form-control-feedback.fab {
  line-height: $input-height-sm;
}

label:not(.form-check-label, .custom-file-label) {
  font-weight: $font-weight-bold;
}

.warning-feedback {
  display: none;
  width: 100%;
  margin-top: $form-feedback-margin-top;
  @include font-size($form-feedback-font-size);
  color: theme-color('warning');
}

.warning-tooltip {
  position: absolute;
  top: 100%;
  z-index: 5;
  display: none;
  max-width: 100%; // Contain to parent when possible
  padding: $form-feedback-tooltip-padding-y $form-feedback-tooltip-padding-x;
  margin-top: .1rem;
  @include font-size($form-feedback-tooltip-font-size);
  line-height: $form-feedback-tooltip-line-height;
  color: color-yiq(theme-color('warning'));
  background-color: rgba(theme-color('warning'), $form-feedback-tooltip-opacity);
  @include border-radius($form-feedback-tooltip-border-radius);
}

.form-control {
  &.is-warning {
    border-color: theme-color('warning');

    @if $enable-validation-icons {
      // padding-right: $input-height-inner;
      // background-image: none;
      // background-repeat: no-repeat;
      // background-position: center right $input-height-inner-quarter;
      // background-size: $input-height-inner-half $input-height-inner-half;
    }

    &:focus {
      border-color: theme-color('warning');
      box-shadow: 0 0 0 $input-focus-width rgba(theme-color('warning'), .25);
    }

    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }
  }
}

// stylelint-disable-next-line selector-no-qualifying-type
textarea.form-control {
  &.is-warning {
    @if $enable-validation-icons {
      padding-right: $input-height-inner;
      background-position: top $input-height-inner-quarter right $input-height-inner-quarter;
    }
  }
}

.custom-select {
  &.is-warning {
    border-color: theme-color('warning');

    @if $enable-validation-icons {
      // padding-right: $custom-select-feedback-icon-padding-right;
      // background: $custom-select-background, none $custom-select-bg no-repeat $custom-select-feedback-icon-position / $custom-select-feedback-icon-size;
    }

    &:focus {
      border-color: theme-color('warning');
      box-shadow: 0 0 0 $input-focus-width rgba(theme-color('warning'), .25);
    }

    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }
  }
}


.form-control-file {
  &.is-warning {
    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }
  }
}

.form-check-input {
  &.is-warning {
    ~ .form-check-label {
      color: theme-color('warning');
    }

    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }
  }
}

.custom-control-input {
  &.is-warning {
    ~ .custom-control-label {
      color: theme-color('warning');

      &::before {
        border-color: theme-color('warning');
      }
    }

    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }

    &:checked {
      ~ .custom-control-label::before {
        border-color: lighten(theme-color('warning'), 10%);
        @include gradient-bg(lighten(theme-color('warning'), 10%));
      }
    }

    &:focus {
      ~ .custom-control-label::before {
        box-shadow: 0 0 0 $input-focus-width rgba(theme-color('warning'), .25);
      }

      &:not(:checked) ~ .custom-control-label::before {
        border-color: theme-color('warning');
      }
    }
  }
}

// custom file
.custom-file-input {
  &.is-warning {
    ~ .custom-file-label {
      border-color: theme-color('warning');
    }

    ~ .warning-feedback,
    ~ .warning-tooltip {
      display: block;
    }

    &:focus {
      ~ .custom-file-label {
        border-color: theme-color('warning');
        box-shadow: 0 0 0 $input-focus-width rgba(theme-color('warning'), .25);
      }
    }
  }
}

.custom-switch {
  @each $name, $color in $theme-colors {
    &.custom-switch-off-#{$name} { 
      & .custom-control-input ~ .custom-control-label::before {
        background-color: #{$color};
        border-color: darken($color, 20%);
      }
      & .custom-control-input ~ .custom-control-label::after {
        background-color: darken($color, 25%);
      }
    }
    &.custom-switch-on-#{$name} { 
      & .custom-control-input:checked ~ .custom-control-label::before {
        background-color: #{$color};
        border-color: darken($color, 20%);
      }
      & .custom-control-input:checked ~ .custom-control-label::after {
        background-color: lighten($color, 30%);
      }
    }
  }

  // Background colors (colors)
  @each $name, $color in $colors {
    &.custom-switch-off-#{$name} { 
      & .custom-control-input ~ .custom-control-label::before {
        background-color: #{$color};
        border-color: darken($color, 20%);
      }
      & .custom-control-input ~ .custom-control-label::after {
        background-color: darken($color, 25%);
      }
    }
    &.custom-switch-on-#{$name} { 
      & .custom-control-input:checked ~ .custom-control-label::before {
        background-color: #{$color};
        border-color: darken($color, 20%);
      }
      & .custom-control-input:checked ~ .custom-control-label::after {
        background-color: lighten($color, 30%);
      }
    }
  }  
}