For AI agents: the complete documentation index is available at https://nhanbe.id.vn/llms.txt, the full documentation bundle is available at https://nhanbe.id.vn/llms-full.txt, and this page is available as Markdown at https://nhanbe.id.vn/building-for-the-web/web-content/forms-and-interactions.md.
Nhan AEM Notes

Link text, navigation labels, form field labels, error messages, and mobile-first DOM order so users can act on the content you've structured.

Forms and interactions

Once a page tells users what you offer, they need to act on it - click a link, fill a form, navigate elsewhere. Interaction copy and field affordances decide whether they succeed without thinking. Back to the section overview.

Link text should make sense out of context (avoid "click here"). Match nav labels to page titles when reasonable.

Do

<p>
    Read the full
    <a href="/legal/privacy/">privacy policy</a>
    before you enable analytics cookies.
</p>

<nav aria-label="Breadcrumb">
    <ol>
        <li><a href="/docs/">Documentation</a></li>
        <li><a href="/docs/api/">API</a></li>
        <li aria-current="page">Authentication</li>
    </ol>
</nav>

Don't

<p>
    For more information about how we handle data,
    <a href="/legal/privacy/">click here</a>.
</p>

Forms

Every control needs a visible label. Placeholder text is not a label. Associate errors with fields and write specific messages.

Do

<form>
    <div class="field">
        <label for="email">Work email</label>
        <input
            id="email"
            name="email"
            type="email"
            autocomplete="email"
            required
            aria-describedby="email-hint"
        >
        <p id="email-hint" class="hint">We send receipts and security alerts here.</p>
        <p id="email-error" class="error" hidden><!-- filled when invalid --></p>
    </div>
</form>

Don't

<!-- Placeholder as only label; error only at top of form -->
<form>
    <p class="form-error">There were errors with your submission.</p>
    <input placeholder="Email address *">
</form>

Do (inline, actionable error)

<label for="postal">Postal code</label>
<input
    id="postal"
    name="postal"
    type="text"
    inputmode="numeric"
    aria-invalid="true"
    aria-describedby="postal-error"
>
<p id="postal-error" class="error">
    Enter a valid German postcode (five digits).
</p>

Mobile-first content order

Put the main answer early in the DOM so small screens and assistive tech hit it first - not only below a huge decorative hero.

Do

<main>
    <h1>Opening hours</h1>
    <p>Monday–Friday 9:00–17:00 CET. Closed on public holidays in Berlin.</p>
    <figure class="hero-visual">
        <img src="/img/storefront.webp" alt="">
    </figure>
</main>

Don't

<!-- Critical facts only after large imagery -->
<main>
    <img class="hero-fullbleed" src="/img/campaign.webp" alt="">
    <h1>Opening hours</h1>
    <p>Monday–Friday 9:00–17:00...</p>
</main>