Navigation · Complete runnable example
Keep a section index in step with the current reading position.
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<title>MRHTML | Keep your place.</title>
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select {
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summary {
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</style>
</head>
<body>
<header class="header wrap">
<span class="brand"
><span class="mark" aria-hidden="true">m.</span>MRHTML / Workshop</span
>
<p>SMALL PATTERNS.<br />CONSIDERED DETAILS.</p>
</header>
<main class="wrap">
<div class="intro">
<p class="eyebrow">05 / ACTIVE TABLE OF CONTENTS</p>
<h1>Keep your place.</h1>
<p>
A short field guide to thoughtful prototypes. The section index
follows your reading position and remains ordinary anchor navigation
without JavaScript.
</p>
</div>
<noscript
><p>
The section links still work as normal anchors. Automatic
current-section highlighting requires JavaScript.
</p></noscript
>
<div class="reading-layout">
<nav class="contents" aria-label="On this page">
<p class="small">ON THIS PAGE</p>
<a href="#question"><span>01</span>Start with a question</a
><a href="#shape"><span>02</span>Give the idea a shape</a
><a href="#observe"><span>03</span>Watch the awkward moments</a
><a href="#record"><span>04</span>Leave a useful record</a>
<p class="contents-note">
Four notes.<br />One useful starting point.
</p>
</nav>
<article class="essay" aria-label="A thoughtful prototype">
<section
id="question"
class="essay-section"
aria-labelledby="heading-question"
>
<p class="eyebrow">FIELD NOTE / 01</p>
<h2 id="heading-question" tabindex="-1">Start with a question</h2>
<p>
Before choosing a format, write down the uncertainty you want to
resolve. A useful question names the people involved and the
decision that comes next.
</p>
<p>
A small prototype can test whether the language is understandable.
It cannot establish whether an entire product will succeed. Match
the question to something you can actually observe.
</p>
<aside class="question">
<span>ASK YOURSELF</span>
<p>What would you need to see before changing direction?</p>
</aside>
</section>
<section
id="shape"
class="essay-section"
aria-labelledby="heading-shape"
>
<p class="eyebrow">FIELD NOTE / 02</p>
<h2 id="heading-shape" tabindex="-1">Give the idea a shape</h2>
<p>
Choose a small, complete example. Real labels and realistic
content reveal more than empty boxes, especially when the text is
long or the screen is narrow.
</p>
<p>
Keep the structure plain enough to change. Separate the essential
behavior from decorative polish so an early revision does not
require rebuilding every detail.
</p>
<aside class="question">
<span>ASK YOURSELF</span>
<p>What is the smallest honest version of this idea?</p>
</aside>
</section>
<section
id="observe"
class="essay-section"
aria-labelledby="heading-observe"
>
<p class="eyebrow">FIELD NOTE / 03</p>
<h2 id="heading-observe" tabindex="-1">
Watch the awkward moments
</h2>
<p>
Try the example with a keyboard, a narrow screen, and an
unfamiliar task. Notice where you hesitate, where focus goes, and
which labels need explanation.
</p>
<p>
An empty result or a failed action is still part of the interface.
Write those messages while the behavior is small enough to
understand, then test that the result matches the words.
</p>
<aside class="question">
<span>ASK YOURSELF</span>
<p>What happens when the comfortable path is interrupted?</p>
</aside>
</section>
<section
id="record"
class="essay-section"
aria-labelledby="heading-record"
>
<p class="eyebrow">FIELD NOTE / 04</p>
<h2 id="heading-record" tabindex="-1">Leave a useful record</h2>
<p>
Write down what changed, what remains uncertain, and why a
particular tradeoff was acceptable. The next person needs context
as much as they need the current files.
</p>
<p>
Keep observations separate from promises. A short trial can reveal
a problem without proving that it has been solved for every person
or device.
</p>
<aside class="question">
<span>ASK YOURSELF</span>
<p>What will someone need to know when they revisit this?</p>
</aside>
</section>
</article>
</div>
<p class="note">
The index reflects scroll position, not reading completion. No progress
or browsing history is stored.
</p>
</main>
<footer class="footer wrap">
<span>MRHTML / Original runnable example</span
><span>Local content. No network required.</span>
</footer>
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