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Form: Styling


Can be provided via the label attribute, but the slot can be used to change the html and CSS of the label. For example add an u-sr-only class to the label to make it (partially) visually hidden. A label is always needed for accessibility reasons.

export const label = () => html`
    .u-sr-only {
      position: absolute;
      width: 1px;
      height: 1px;
      overflow: hidden;
      clip-path: inset(100%);
      clip: rect(1px, 1px, 1px, 1px);
      white-space: nowrap;
      border: 0;
      margin: 0;
      padding: 0;
    <label slot="label"
      >Label <span class="u-sr-only">partially only visible for screen-readers</span></label

Input additions

When using an addition to the input you could add data-label to add the content connected to the input via aria-labelledby or add data-description to connect it via the aria-describedby when the content is relevant for the screen-reader user to fill in the form field. This won't be necessary for a search icon, since that should already be clear via the label, but it is relevant in case a unit is added behind the input field.


The prefix is used for addons to the input like a minus button in the input-stepper.

<lion-input label="Prefix">
  <div slot="prefix" data-description>[prefix]</div>


The suffix can be used for addons to the input like a calculator, datepicker or addressbook. In these cases a button with an icon is used.

<lion-input label="Suffix">
  <div slot="suffix" data-description>[suffix]</div>


Before slot does not have an active use case yet.

<lion-input label="Before">
  <div slot="before" data-description>[before]</div>


The after is mostly used to add a unit to the input field, such as a currency or percentage.

<lion-input label="Amount">
  <div slot="after" data-description>EUR</div>
<lion-input label="Percentage">
  <div slot="after" data-description>%</div>


Due to our custom inputs being Web Components, it is possible to put HTML content inside an input. For example if you want to add a button as a prefix or suffix.

<lion-input label="Prefix and suffix">
  <lion-button slot="prefix">prefix</lion-button>
  <lion-button slot="suffix">suffix</lion-button>