#Article:

[jcmarchi]

How to Create Multi-Step Forms With Vanilla JavaScript and CSS

New Post has been published on https://thedigitalinsider.com/how-to-create-multi-step-forms-with-vanilla-javascript-and-css/

How to Create Multi-Step Forms With Vanilla JavaScript and CSS

Multi-step forms are a good choice when your form is large and has many controls. No one wants to scroll through a super-long form on a mobile device. By grouping controls on a screen-by-screen basis, we can improve the experience of filling out long, complex forms.

But when was the last time you developed a multi-step form? Does that even sound fun to you? There’s so much to think about and so many moving pieces that need to be managed that I wouldn’t blame you for resorting to a form library or even some type of form widget that handles it all for you.

But doing it by hand can be a good exercise and a great way to polish the basics. I’ll show you how I built my first multi-step form, and I hope you’ll not only see how approachable it can be but maybe even spot areas to make my work even better.

We’ll walk through the structure together. We’ll build a job application, which I think many of us can relate to these recent days. I’ll scaffold the baseline HTML, CSS, and JavaScript first, and then we’ll look at considerations for accessibility and validation.

I’ve created a GitHub repo for the final code if you want to refer to it along the way.

The structure of a multi-step form

Our job application form has four sections, the last of which is a summary view, where we show the user all their answers before they submit them. To achieve this, we divide the HTML into four sections, each identified with an ID, and add navigation at the bottom of the page. I’ll give you that baseline HTML in the next section.

Navigating the user to move through sections means we’ll also include a visual indicator for what step they are at and how many steps are left. This indicator can be a simple dynamic text that updates according to the active step or a fancier progress bar type of indicator. We’ll do the former to keep things simple and focused on the multi-step nature of the form.,

The structure and basic styles

We’ll focus more on the logic, but I will provide the code snippets and a link to the complete code at the end.

Let’s start by creating a folder to hold our pages. Then, create an index.html file and paste the following into it:

Open HTML

<form id="myForm"> <section class="group-one" id="one"> <div class="form-group"> <div class="form-control"> <label for="name">Name <span style="color: red;">*</span></label> <input type="text" id="name" name="name" placeholder="Enter your name"> </div> <div class="form-control"> <label for="idNum">ID number <span style="color: red;">*</span></label> <input type="number" id="idNum" name="idNum" placeholder="Enter your ID number"> </div> </div> <div class="form-group"> <div class="form-control"> <label for="email">Email <span style="color: red;">*</span></label> <input type="email" id="email" name="email" placeholder="Enter your email"> </div> <div class="form-control"> <label for="birthdate">Date of Birth <span style="color: red;">*</span></label> <input type="date" id="birthdate" name="birthdate" max="2006-10-01" min="1924-01-01"> </div> </div> </section> <section class="group-two" id="two"> <div class="form-control"> <label for="document">Upload CV <span style="color: red;">*</span></label> <input type="file" name="document" id="document"> </div> <div class="form-control"> <label for="department">Department <span style="color: red;">*</span></label> <select id="department" name="department"> <option value="">Select a department</option> <option value="hr">Human Resources</option> <option value="it">Information Technology</option> <option value="finance">Finance</option> </select> </div> </section> <section class="group-three" id="three"> <div class="form-control"> <label for="skills">Skills (Optional)</label> <textarea id="skills" name="skills" rows="4" placeholder="Enter your skills"></textarea> </div> <div class="form-control"> <input type="checkbox" name="terms" id="terms"> <label for="terms">I agree to the terms and conditions <span style="color: red;">*</span></label> </div> <button id="btn" type="submit">Confirm and Submit</button> </section> <div class="arrows"> <button type="button" id="navLeft">Previous</button> <span id="stepInfo"></span> <button type="button" id="navRight">Next</button> </div> </form> <script src="script.js"></script>

Looking at the code, you can see three sections and the navigation group. The sections contain form inputs and no native form validation. This is to give us better control of displaying the error messages because native form validation is only triggered when you click the submit button.

Next, create a styles.css file and paste this into it:

Open base styles

:root --primary-color: #8c852a; --secondary-color: #858034; body font-family: sans-serif; line-height: 1.4; margin: 0 auto; padding: 20px; background-color: #f4f4f4; max-width: 600px; h1 text-align: center; form background: #fff; padding: 40px; border-radius: 5px; box-shadow: 0 0 10px rgba(0, 0, 0, 0.1); display: flex; flex-direction: column; .form-group display: flex; gap: 7%; .form-group > div width: 100%; input:not([type="checkbox"]), select, textarea width: 100%; padding: 8px; border: 1px solid #ddd; border-radius: 4px; .form-control margin-bottom: 15px; button display: block; width: 100%; padding: 10px; color: white; background-color: var(--primary-color); border: none; border-radius: 4px; cursor: pointer; font-size: 16px; button:hover background-color: var(--secondary-color); .group-two, .group-three display: none; .arrows display: flex; justify-content: space-between align-items: center; margin-top: 10px; #navLeft, #navRight width: fit-content; @media screen and (max-width: 600px) .form-group flex-direction: column;

Open up the HTML file in the browser, and you should get something like the two-column layout in the following screenshot, complete with the current page indicator and navigation.

Adding functionality with vanilla JavaScript

Now, create a script.js file in the same directory as the HTML and CSS files and paste the following JavaScript into it:

Open base scripts

const stepInfo = document.getElementById("stepInfo"); const navLeft = document.getElementById("navLeft"); const navRight = document.getElementById("navRight"); const form = document.getElementById("myForm"); const formSteps = ["one", "two", "three"]; let currentStep = 0; function updateStepVisibility() formSteps.forEach((step) => document.getElementById(step).style.display = "none"; ); document.getElementById(formSteps[currentStep]).style.display = "block"; stepInfo.textContent = `Step $currentStep + 1 of $formSteps.length`; navLeft.style.display = currentStep === 0 ? "none" : "block"; navRight.style.display = currentStep === formSteps.length - 1 ? "none" : "block"; document.addEventListener("DOMContentLoaded", () => navLeft.style.display = "none"; updateStepVisibility(); navRight.addEventListener("click", () => if (currentStep < formSteps.length - 1) currentStep++; updateStepVisibility(); ); navLeft.addEventListener("click", () => if (currentStep > 0) currentStep--; updateStepVisibility(); ); );

This script defines a method that shows and hides the section depending on the formStep values that correspond to the IDs of the form sections. It updates stepInfo with the current active section of the form. This dynamic text acts as a progress indicator to the user.

It then adds logic that waits for the page to load and click events to the navigation buttons to enable cycling through the different form sections. If you refresh your page, you will see that the multi-step form works as expected.

Multi-step form navigation

Let’s dive deeper into what the Javascript code above is doing. In the updateStepVisibility() function, we first hide all the sections to have a clean slate:

formSteps.forEach((step) => document.getElementById(step).style.display = "none"; );

Then, we show the currently active section:

document.getElementById(formSteps[currentStep]).style.display = "block";`

Next, we update the text that indicators progress through the form:

stepInfo.textContent = `Step $currentStep + 1 of $formSteps.length`;

Finally, we hide the Previous button if we are at the first step and hide the Next button if we are at the last section:

navLeft.style.display = currentStep === 0 ? "none" : "block"; navRight.style.display = currentStep === formSteps.length - 1 ? "none" : "block";

Let’s look at what happens when the page loads. We first hide the Previous button as the form loads on the first section:

document.addEventListener("DOMContentLoaded", () => navLeft.style.display = "none"; updateStepVisibility();

Then we grab the Next button and add a click event that conditionally increments the current step count and then calls the updateStepVisibility() function, which then updates the new section to be displayed:

navRight.addEventListener("click", () => if (currentStep < formSteps.length - 1) currentStep++; updateStepVisibility(); );

Finally, we grab the Previous button and do the same thing but in reverse. Here, we are conditionally decrementing the step count and calling the updateStepVisibility():

navLeft.addEventListener("click", () => if (currentStep > 0) currentStep--; updateStepVisibility(); );

Handling errors

Have you ever spent a good 10+ minutes filling out a form only to submit it and get vague errors telling you to correct this and that? I prefer it when a form tells me right away that something’s amiss so that I can correct it before I ever get to the Submit button. That’s what we’ll do in our form.

Our principle is to clearly indicate which controls have errors and give meaningful error messages. Clear errors as the user takes necessary actions. Let’s add some validation to our form. First, let’s grab the necessary input elements and add this to the existing ones:

const nameInput = document.getElementById("name"); const idNumInput = document.getElementById("idNum"); const emailInput = document.getElementById("email"); const birthdateInput = document.getElementById("birthdate") const documentInput = document.getElementById("document"); const departmentInput = document.getElementById("department"); const termsCheckbox = document.getElementById("terms"); const skillsInput = document.getElementById("skills");

Then, add a function to validate the steps:

Open validation script

function validateStep(step)

Here, we check if each required input has some value and if the email input has a valid input. Then, we set the isValid boolean accordingly. We also call a showError() function, which we haven’t defined yet.

Paste this code above the validateStep() function:

function showError(input, message) const formControl = input.parentElement; const errorSpan = formControl.querySelector(".error-message"); input.classList.add("error"); errorSpan.textContent = message;

Now, add the following styles to the stylesheet:

Open validation styles

input:focus, select:focus, textarea:focus outline: .5px solid var(--primary-color); input.error, select.error, textarea.error outline: .5px solid red; .error-message font-size: x-small; color: red; display: block; margin-top: 2px; .arrows color: var(--primary-color); font-size: 18px; font-weight: 900; #navLeft, #navRight display: flex; align-items: center; gap: 10px; #stepInfo color: var(--primary-color);

If you refresh the form, you will see that the buttons do not take you to the next section till the inputs are considered valid:

Finally, we want to add real-time error handling so that the errors go away when the user starts inputting the correct information. Add this function below the validateStep() function:

Open real-time validation script

function setupRealtimeValidation() nameInput.addEventListener("input", () => if (nameInput.value.trim() !== "") clearError(nameInput); ); idNumInput.addEventListener("input", () => if (idNumInput.value.trim() !== "") clearError(idNumInput); ); emailInput.addEventListener("input", () => if (emailInput.validity.valid) clearError(emailInput); ); birthdateInput.addEventListener("change", () => if (birthdateInput.value !== "") clearError(birthdateInput); ); documentInput.addEventListener("change", () => if (documentInput.files[0]) clearError(documentInput); ); departmentInput.addEventListener("change", () => if (departmentInput.value !== "") clearError(departmentInput); ); termsCheckbox.addEventListener("change", () => if (termsCheckbox.checked) clearError(termsCheckbox); );

This function clears the errors if the input is no longer invalid by listening to input and change events then calling a function to clear the errors. Paste the clearError() function below the showError() one:

function clearError(input) const formControl = input.parentElement; const errorSpan = formControl.querySelector(".error-message"); input.classList.remove("error"); errorSpan.textContent = "";

And now the errors clear when the user types in the correct value:

The multi-step form now handles errors gracefully. If you do decide to keep the errors till the end of the form, then at the very least, jump the user back to the erroring form control and show some indication of how many errors they need to fix.

Handling form submission

In a multi-step form, it is valuable to show the user a summary of all their answers at the end before they submit and to offer them an option to edit their answers if necessary. The person can’t see the previous steps without navigating backward, so showing a summary at the last step gives assurance and a chance to correct any mistakes.

Let’s add a fourth section to the markup to hold this summary view and move the submit button within it. Paste this just below the third section in index.html:

Open HTML

<section class="group-four" id="four"> <div class="summary-section"> <p>Name: </p> <p id="name-val"></p> <button type="button" class="edit-btn" id="name-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>ID Number: </p> <p id="id-val"></p> <button type="button" class="edit-btn" id="id-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>Email: </p> <p id="email-val"></p> <button type="button" class="edit-btn" id="email-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>Date of Birth: </p> <p id="bd-val"></p> <button type="button" class="edit-btn" id="bd-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>CV/Resume: </p> <p id="cv-val"></p> <button type="button" class="edit-btn" id="cv-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>Department: </p> <p id="dept-val"></p> <button type="button" class="edit-btn" id="dept-edit"> <span>✎</span> <span>Edit</span> </button> </div> <div class="summary-section"> <p>Skills: </p> <p id="skills-val"></p> <button type="button" class="edit-btn" id="skills-edit"> <span>✎</span> <span>Edit</span> </button> </div> <button id="btn" type="submit">Confirm and Submit</button> </section>

Then update the formStep in your Javascript to read:

const formSteps = ["one", "two", "three", "four"];

Finally, add the following classes to styles.css:

.summary-section display: flex; align-items: center; gap: 10px; .summary-section p:first-child width: 30%; flex-shrink: 0; border-right: 1px solid var(--secondary-color); .summary-section p:nth-child(2) width: 45%; flex-shrink: 0; padding-left: 10px; .edit-btn width: 25%; margin-left: auto; background-color: transparent; color: var(--primary-color); border: .7px solid var(--primary-color); border-radius: 5px; padding: 5px; .edit-btn:hover border: 2px solid var(--primary-color); font-weight: bolder; background-color: transparent;

Now, add the following to the top of the script.js file where the other consts are:

const nameVal = document.getElementById("name-val"); const idVal = document.getElementById("id-val"); const emailVal = document.getElementById("email-val"); const bdVal = document.getElementById("bd-val") const cvVal = document.getElementById("cv-val"); const deptVal = document.getElementById("dept-val"); const skillsVal = document.getElementById("skills-val"); const editButtons = "name-edit": 0, "id-edit": 0, "email-edit": 0, "bd-edit": 0, "cv-edit": 1, "dept-edit": 1, "skills-edit": 2 ;

Then add this function in scripts.js:

function updateSummaryValues() nameVal.textContent = nameInput.value; idVal.textContent = idNumInput.value; emailVal.textContent = emailInput.value; bdVal.textContent = birthdateInput.value; const fileName = documentInput.files[0]?.name; if (fileName) const extension = fileName.split(".").pop(); const baseName = fileName.split(".")[0]; const truncatedName = baseName.length > 10 ? baseName.substring(0, 10) + "..." : baseName; cvVal.textContent = `$truncatedName.$extension`; else cvVal.textContent = "No file selected"; deptVal.textContent = departmentInput.value; skillsVal.textContent = skillsInput.value || "No skills submitted"; }

This dynamically inserts the input values into the summary section of the form, truncates the file names, and offers a fallback text for the input that was not required.

Then update the updateStepVisibility() function to call the new function:

function updateStepVisibility() formSteps.forEach((step) => document.getElementById(step).style.display = "none"; ); document.getElementById(formSteps[currentStep]).style.display = "block"; stepInfo.textContent = `Step $currentStep + 1 of $formSteps.length`; if (currentStep === 3) updateSummaryValues(); navLeft.style.display = currentStep === 0 ? "none" : "block"; navRight.style.display = currentStep === formSteps.length - 1 ? "none" : "block";

Finally, add this to the DOMContentLoaded event listener:

Object.keys(editButtons).forEach((buttonId) => const button = document.getElementById(buttonId); button.addEventListener("click", (e) => currentStep = editButtons[buttonId]; updateStepVisibility(); ); );

Running the form, you should see that the summary section shows all the inputted values and allows the user to edit any before submitting the information:

And now, we can submit our form:

form.addEventListener("submit", (e) => e.preventDefault(); if (validateStep(2)) alert("Form submitted successfully!"); form.reset(); currentFormStep = 0; updateStepVisibility(); );

Our multi-step form now allows the user to edit and see all the information they provide before submitting it.

Accessibility tips

Making multi-step forms accessible starts with the basics: using semantic HTML. This is half the battle. It is closely followed by using appropriate form labels.

Other ways to make forms more accessible include giving enough room to elements that must be clicked on small screens and giving meaningful descriptions to the form navigation and progress indicators.

Offering feedback to the user is an important part of it; it’s not great to auto-dismiss user feedback after a certain amount of time but to allow the user to dismiss it themselves. Paying attention to contrast and font choice is important, too, as they both affect how readable your form is.

Let’s make the following adjustments to the markup for more technical accessibility:

Add aria-required="true" to all inputs except the skills one. This lets screen readers know the fields are required without relying on native validation.

Add role="alert" to the error spans. This helps screen readers know to give it importance when the input is in an error state.

Add role="status" aria-live="polite" to the .stepInfo. This will help screen readers understand that the step info keeps tabs on a state, and the aria-live being set to polite indicates that should the value change, it does not need to immediately announce it.

In the script file, replace the showError() and clearError() functions with the following:

function showError(input, message) const formControl = input.parentElement; const errorSpan = formControl.querySelector(".error-message"); input.classList.add("error"); input.setAttribute("aria-invalid", "true"); input.setAttribute("aria-describedby", errorSpan.id); errorSpan.textContent = message; function clearError(input) const formControl = input.parentElement; const errorSpan = formControl.querySelector(".error-message"); input.classList.remove("error"); input.removeAttribute("aria-invalid"); input.removeAttribute("aria-describedby"); errorSpan.textContent = "";

Here, we programmatically add and remove attributes that explicitly tie the input with its error span and show that it is in an invalid state.

Finally, let’s add focus on the first input of every section; add the following code to the end of the updateStepVisibility() function:

const currentStepElement = document.getElementById(formSteps[currentStep]); const firstInput = currentStepElement.querySelector( "input, select, textarea" ); if (firstInput) firstInput.focus();

And with that, the multi-step form is much more accessible.

Conclusion

There we go, a four-part multi-step form for a job application! As I said at the top of this article, there’s a lot to juggle — so much so that I wouldn’t fault you for looking for an out-of-the-box solution.

But if you have to hand-roll a multi-step form, hopefully now you see it’s not a death sentence. There’s a happy path that gets you there, complete with navigation and validation, without turning away from good, accessible practices.

And this is just how I approached it! Again, I took this on as a personal challenge to see how far I could get, and I’m pretty happy with it. But I’d love to know if you see additional opportunities to make this even more mindful of the user experience and considerate of accessibility.

References

Here are some relevant links I referred to when writing this article:

How to Structure a Web Form (MDN)

Multi-page Forms (W3C.org)

Create accessible forms (A11y Project)

[longreads]

How Concerned Citizens Drove a Neo-Nazi Out of Rural Maine

Christopher Pohlhaus planned to build a fascist training compound in the woods of rural Maine. The local journalists, veterans, lumberjacks, and policymakers weren't having it.

Pohlhaus, 37, is a former U.S. marine, an itinerant tattoo artist, and a hardcore white-supremacist influencer. He is loud and hostile, and proud to be both. His voice is pitched surprisingly high, and he has a slight Southern drawl. He has a large body and small bald head; a blue-black tattoo crawls up the right side of his face, from his chin to his forehead. Over the years, Pohlhaus has collected thousands of social media followers, who know him by his nickname: Hammer.

Hammer had been living in Texas for a few years when, in March 2022, he bought the land in Maine. He told his followers that he was going to use it to build a haven, operational center, and training ground for white supremacists.

Check out our excerpt of The Atavist’s latest blockbuster story. 

[389]

PORTO ROCHA

[nanaluvbug]

🧀🥪🌶️🥭 The Ravening War portraits  🧀🥪🌶️🥭

patreon * twitch * shop  

[ID: a series of digitally illustrated portraits showing - top left to bottom right - Bishop Raphaniel Charlock (an old radish man with a big red head and large white eyebrows & a scraggly beard. he wears green and gold robes with symbols of the bulb and he smirks at the viewer) Karna Solara (a skinny young chili pepper woman with wavy green hair, freckled light green skin with red blooms on her cheeks. she wears a chili pepper hood lined with small pepper seeds and stares cagily ahead) Thane Delissandro Katzon (a muscular young beef man with bright pinkish skin with small skin variations to resemble pastrami and dark burgundy hair. he wears a bread headress with a swirl of rye covering his ears and he looks ahead, optimistic and determined) Queen Amangeaux Epicée du Peche (a bright mango woman with orange skin, big red hair adorned with a green laurel, and sparkling green/gold makeup. she wears large gold hoop earrings and a high leafy collar) and Colin Provolone (a scraggly cheese man with waxy yellow skin and dark slicked back hair and patchy dark facial hair. he wears a muted, ratty blue bandana around his neck and raises a scarred brow at the viewer with a smirk) End ID.)

[70sscifiart]

One of my favorites by Paul Lehr, used as a 1971 cover to "Earth Abides," by George R. Stewart. It's also in my upcoming art book!

[taizooo]

もともとは10年ほど前にTumblrにすごくハマっていて。いろんな人をフォローしたらかっこいい写真や色が洪水のように出てきて、もう自分で絵を描かなくて良いじゃん、ってなったんです。それで何年も画像を集めていって、そこで集まった色のイメージやモチーフ、レンズの距離感など画面構成を抽象化して、いまの感覚にアウトプットしています。画像の持つ情報量というものが作品の影響になっていますね。

映画『きみの色』山田尚子監督×はくいきしろい対談。嫉妬し合うふたりが語る、色と光の表現｜Tokyo Art Beat

[layla-keating]

#thistension

XO, KITTY — 1.09 “SNAFU”

[nevver]

No one wants to be here and no one wants to leave, Dave Smith (because)

[foodffs]

Noodles with Lamb Sauce (Laghman, 新疆拌面) Xinjiang laghman features chewy noodles served with a bold and rich lamb and tomato sauce that is bursting with flavor.

Recipe: https://omnivorescookbook.com/recipes/uyghur-style-noodles-with-lamb-sauce

[jcmarchi]

Yet Another Anchor Positioning Quirk

New Post has been published on https://thedigitalinsider.com/yet-another-anchor-positioning-quirk/

Yet Another Anchor Positioning Quirk

I strongly believe Anchor Positioning will go down as one of the greatest additions to CSS. It may not be as game-changing as Flexbox or Grid, but it does fill a positioning gap that has been missing for decades. As awesome as I think it is, CSS Anchor Positioning has a lot of quirks, some of which are the product of its novelty and others due to its unique way of working. Today, I want to bring you yet another Anchor Positioning quirk that has bugged me since I first saw it.

The inception

It all started a month ago when I was reading about what other people have made using Anchor Positioning, specifically this post by Temani Afif about “Anchor Positioning & Scroll-Driven Animations.” I strongly encourage you to read it and find out what caught my eye there. Combining Anchor Positioning and Scroll-Driven Animation, he makes a range slider that changes colors while it progresses.

Amazing by itself, but it’s interesting that he is using two target elements with the same anchor name, each attached to its corresponding anchor, just like magic. If this doesn’t seem as interesting as it looks, we should then briefly recap how Anchor Positioning works.

CSS Anchor Positioning and the anchor-scope property

See our complete CSS Anchor Positioning Guide for a comprehensive deep dive.

Anchor Positioning brings two new concepts to CSS, an anchor element and a target element. The anchor is the element used as a reference for positioning other elements, hence the anchor name. While the target is an absolutely-positioned element placed relative to one or more anchors.

An anchor and a target can be almost every element, so you can think of them as just two div sitting next to each other:

<div class="anchor">anchor</div> <div class="target">target</div>

To start, we first have to register the anchor element in CSS using the anchor-name property:

.anchor anchor-name: --my-anchor;

And the position-anchor property on an absolutely-positioned element attaches it to an anchor of the same name. However, to move the target around the anchor we need the position-area property.

.target position: absolute; position-anchor: --my-anchor; position-area: top right;

This works great, but things get complicated if we change our markup to include more anchors and targets:

<ul> <li> <div class="anchor">anchor 1</div> <div class="target">target 1</div> </li> <li> <div class="anchor">anchor 2</div> <div class="target">target 2</div> </li> <li> <div class="anchor">anchor 3</div> <div class="target">target 3</div> </li> </ul>

Instead of each target attaching to its closest anchor, they all pile up at the last registered anchor in the DOM.

The anchor-scope property was introduced in Chrome 131 as an answer to this issue. It limits the scope of anchors to a subtree so that each target attaches correctly. However, I don’t want to focus on this property, because what initially caught my attention was that Temani didn’t use it. For some reason, they all attached correctly, again, like magic.

What’s happening?

Targets usually attach to the last anchor on the DOM instead of their closest anchor, but in our first example, we saw two anchors with the same anchor-name and their corresponding targets attached. All this without the anchor-scope property. What’s happening?

Two words: Containing Block.

Something to know about Anchor Positioning is that it relies a lot on how an element’s containing block is built. This isn’t something inherently from Anchor Positioning but from absolute positioning. Absolute elements are positioned relative to their containing block, and inset properties like top: 0px, left: 30px or inset: 1rem are just moving an element around its containing block boundaries, creating what’s called the inset-modified containing block.

A target attached to an anchor isn’t any different, and what the position-area property does under the table is change the target’s inset-modified containing block so it is right next to the anchor.

Usually, the containing block of an absolutely-positioned element is the whole viewport, but it can be changed by any ancestor with a position other than static (usually relative). Temani takes advantage of this fact and creates a new containing block for each slider, so they can only be attached to their corresponding anchors. If you snoop around the code, you can find it at the beginning:

label position: relative; /* No, It's not useless so don't remove it (or remove it and see what happens) */

If we use this tactic on our previous examples, suddenly they are all correctly attached!

Yet another quirk

We didn’t need to use the anchor-scope property to attach each anchor to its respective target, but instead took advantage of how the containing block of absolute elements is computed. However, there is yet another approach, one that doesn’t need any extra bits of code.

This occurred to me when I was also experimenting with Scroll-Driven Animations and Anchor Positioning and trying to attach text-bubble footnotes on the side of a post, like the following:

Logically, each footnote would be a target, but the choice of an anchor is a little more tricky. I initially thought that each paragraph would work as an anchor, but that would mean having more than one anchor with the same anchor-name. The result: all the targets would pile up at the last anchor:

This could be solved using our prior approach of creating a new containing block for each note. However, there is another route we can take, what I call the reductionist method. The problem comes when there is more than one anchor with the same anchor-name, so we will reduce the number of anchors to one, using an element that could work as the common anchor for all targets.

In this case, we just want to position each target on the sides of the post so we can use the entire body of the post as an anchor, and since each target is naturally aligned on the vertical axis, what’s left is to move them along the horizontal axis:

You can better check how it was done on the original post!

Conclusion

The anchor-scope may be the most recent CSS property to be shipped to a browser (so far, just in Chrome 131+), so we can’t expect its support to be something out of this world. And while I would love to use it every now and there, it will remain bound to short demos for a while. This isn’t a reason to limit the use of other Anchor Positioning properties, which are supported in Chrome 125 onwards (and let’s hope in other browsers in the near future), so I hope these little quirks can help you to keep using Anchor Positioning without any fear.

[lesserknownbots]

CJ from Hello World (MSPFA) by phasedsun?

[389]

PORTO ROCHA

[theroyalweekly]

HRH The Princess of Wales in Southport today, on her first engagement since completing chemotherapy. It’s so good to see her!❤️ --

[shitakeo33]

よく「発明は1人でできる。製品化には10人かかる。量産化には100人かかる」とも言われますが、実際に、私はネオジム磁石を1人で発明しました。製品化、量産化については住友特殊金属の仲間たちと一緒に、短期間のうちに成功させました。82年に発明し、83年から生産が始まったのですから、非常に早いです。そしてネオジム磁石は、ハードディスクのＶＣＭ(ボイスコイルモーター)の部品などの電子機器を主な用途として大歓迎を受け、生産量も年々倍増して、2000年には世界で1万トンを超えました。

世界最強「ネオジム磁石はこうして見つけた」（佐川眞人 氏 ／ インターメタリックス株式会社 代表取締役社長） | Science Portal - 科学技術の最新情報サイト「サイエンスポータル」

[kithtaehyung]

AGUST D : DAECHWITA (大吹打) & HAEGEUM (解禁)  ⤷ movie posters | ig ; twt (click for hi-res)