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Accessibility

· 13 checks — Landmarks, headings, alt text, forms, and link quality rolled into one auditable list.
SCORE
47
GRADE
F
FIX
8
REVIEW
5
PASS
0
INFO
0
Checks
13
5 REVIEW 8 FIX
D
Landmark Structure
Action
No landmarks
FIX
No landmarks
Critical::
No <main> landmark found
Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.
Warning::
No <nav> landmark found
Info::
No banner (header) landmark
Info::
No contentinfo (footer) landmark
Warning::
Skip navigation link is missing (WCAG 2.4.1)
Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.

No landmarks detected

Screen reader users have no way to navigate by region.

Screen reader users cannot quickly navigate to the primary content. Wrap your main content in <main>.

Why this matters

Without a <main> landmark, screen-reader users can't skip past the navigation to the page content — every page starts with re-reading the menu.

Learn more ▾

The <main> element marks the page's primary content area. Assistive tech offers a 'jump to main' shortcut — but only if <main> exists. Without it, every page navigation forces re-reading the header. Wrap your primary content in a single <main>.

Source: WAI-ARIA / WCAG 2.4.1

Add a skip link as the first focusable element so keyboard users can bypass repeated navigation.

Why this matters

Without a skip-nav link, keyboard users tab through every nav item before reaching content — every page, every visit.

Learn more ▾

WCAG 2.4.1 (Bypass Blocks) requires a mechanism to skip past repeated content. The standard implementation is a 'Skip to main content' link that's the first focusable element, visually hidden until focused. Three lines of HTML + four of CSS.

Source: WCAG 2.1 SC 2.4.1

F
404 Error Page
Action
HTTP 404, bare page
FIX
HTTP 404, bare page
Info::
Correct 404 status code returned
Got: HTTP 404
Warning::
Bare server default 404 page
The 404 page has no custom styling. Users hitting a broken link see a generic error with no way to navigate back. Add a custom 404 page with your site navigation and a search bar.
404 Page Quality Default 404 Page
Status Code HTTP 404 ✓Page Title 404 Not Found ✓Custom Styling ✗Navigation ✗Homepage Link ✗Search Form ✗
D
Web Manifest
Action
Not found
FIX
Not found
Info::
No web manifest found
No manifest at standard paths (/manifest.json, /site.webmanifest). A manifest is optional but enables PWA features like home screen installation and standalone display.

No web manifest found.

D
Dark Mode Support
Action
No dark mode signals
FIX
No dark mode signals
Info::
No dark mode signals detected
Consider adding CSS with @media (prefers-color-scheme: dark) and <meta name='color-scheme' content='light dark'>.
Info::
Detection limited to meta tags and inline styles
External CSS files may contain prefers-color-scheme rules not visible to this scan.
Dark ModeNo Dark Mode Detected
color-scheme meta Not set ✗Dark theme-color Not set ✗CSS indicators Not detected ✗

Detection limited to meta tags and inline styles.

D
Print Stylesheet
Action
No print styles
FIX
No print styles
Info::
No print-specific styles detected
When users print this page, they get the screen layout including navigation and non-essential elements. Add @media print rules to hide navigation and optimize layout for paper.
Print Stylesheet No Print Styles
Print stylesheet Not found ✗Inline @media print Not detected ✗
F
Navigation UX
Action
No navigation patterns
FIX
No navigation patterns
Info::
No breadcrumbs, search, or skip link detected
These navigation aids help users orient themselves and find content efficiently, especially on large sites.
Breadcrumbs
Search
Skip Link
Labeled Navigation
Back to Top
Hamburger Menu
Sticky Navigation Cannot reliably detect (CSS-based)
0 of 6 testable patterns navigation patterns detected. Limited navigation support. Consider adding breadcrumbs, search, and skip link.
D
Lighthouse Accessibility Audits
Action
Score 69/100 — 6 failing, 16 passed
FIX
69

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Internationalization and localization

If a page doesn't specify a `lang` attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more about the `lang` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
html.home html.home

These are opportunities to improve the interpretation of your content by users in different locales.

Names and labels

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.inner > div.l > a > img div.inner > div.l > a > img

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.d2 > div.block > div.logo > a div.d2 > div.block > div.logo > a
div#slick-slide00 > div > div.child > a.a1 div#slick-slide00 > div > div.child > a.a1
div#slick-slide00 > div > div.child > a.a2 div#slick-slide00 > div > div.child > a.a2
div.inner > div.pic > div.img > a div.inner > div.pic > div.img > a
div.inner > div.pic > div.img > a div.inner > div.pic > div.img > a
div.block > div.list > div.item > a div.block > div.list > div.item > a
div.block > div.list > div.item > a div.block > div.list > div.item > a
div.block > div.list > div.item > a div.block > div.list > div.item > a
div.block > div.list > div.item > a div.block > div.list > div.item > a
div.text > div.inner > div.l > a div.text > div.inner > div.l > a
div.inner > div.pic > div.img > a div.inner > div.pic > div.img > a
div.inner > div.pic > div.img > a div.inner > div.pic > div.img > a
div.block > div.d2 > div#d1 > a div.block > div.d2 > div#d1 > a
div.block > div.d2 > div#d2 > a div.block > div.d2 > div#d2 > a
div.block > div.d2 > div#d3 > a div.block > div.d2 > div#d3 > a
div.block > div.d4 > div#d4 > a div.block > div.d4 > div#d4 > a
div.block > div.d4 > div#d5 > a div.block > div.d4 > div#d5 > a
div.block > div.d4 > div#d6 > a div.block > div.d4 > div#d6 > a
div.part1 > div.list > div.item > a div.part1 > div.list > div.item > a
div.part1 > div.list > div.item > a div.part1 > div.list > div.item > a
div.part1 > div.list > div.item > a div.part1 > div.list > div.item > a
div.part1 > div.list > div.item > a div.part1 > div.list > div.item > a
div.footer > div.part2 > div.logo > a div.footer > div.part2 > div.logo > a

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Best practices

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more about the viewport meta tag.

Why this matters

Informational: a Permissions-Policy directive showing feature -> allowed origins.

Source: MDN Permissions-Policy

Failing Elements
head > meta head > meta

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. Learn more about touch targets.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
新闻 div.part1 > div.nav_foot > div.inner > a
招生 div.part1 > div.nav_foot > div.inner > a
招聘 div.part1 > div.nav_foot > div.inner > a
捐赠 div.part1 > div.nav_foot > div.inner > a
校园地图 div.part1 > div.nav_foot > div.inner > a
校历 div.part1 > div.nav_foot > div.inner > a
燕园特写 div.part1 > div.nav_foot > div.inner > a
未名BBS div.part1 > div.nav_foot > div.inner > a

These items highlight common accessibility best practices.

Navigation

A value greater than 0 implies an explicit navigation ordering. Although technically valid, this often creates frustrating experiences for users who rely on assistive technologies. Learn more about the `tabindex` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
北大 · 要闻 北京大学扎实开展树立和践行正确政绩观学习教育 越南青年“红色研学之旅”之“不忘初心”研学营走进北京大学 世界气象组织秘书长席列斯特·绍罗访问北… body > div.body_b

These are opportunities to improve keyboard navigation in your application.

○Interactive controls are keyboard focusable
○Interactive elements indicate their purpose and state
○The page has a logical tab order
○Visual order on the page follows DOM order
○User focus is not accidentally trapped in a region
○The user's focus is directed to new content added to the page
○HTML5 landmark elements are used to improve navigation
○Offscreen content is hidden from assistive technology
○Custom controls have associated labels
○Custom controls have ARIA roles
●`[aria-*]` attributes match their roles
●`[aria-hidden="true"]` is not present on the document `<body>`
●`[role]`s have all required `[aria-*]` attributes
●`[role]` values are valid
●`[aria-*]` attributes have valid values
●`[aria-*]` attributes are valid and not misspelled
●ARIA attributes are used as specified for the element's role
●`[aria-hidden="true"]` elements do not contain focusable descendents
●Elements use only permitted ARIA attributes
●Background and foreground colors have a sufficient contrast ratio
●Document has a `<title>` element
●Links are distinguishable without relying on color.
●Document has a main landmark.
●Deprecated ARIA roles were not used
●The page contains a heading, skip link, or landmark region
●Identical links have the same purpose.
○`[accesskey]` values are unique
○`button`, `link`, and `menuitem` elements have accessible names
○Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
○ARIA input fields have accessible names
○ARIA `meter` elements have accessible names
○ARIA `progressbar` elements have accessible names
○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
○`[role]`s are contained by their required parent element
○Elements with the `role=text` attribute do not have focusable descendents.
○ARIA toggle fields have accessible names
○ARIA `tooltip` elements have accessible names
○ARIA `treeitem` elements have accessible names
○Buttons have an accessible name
○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
○Definition list items are wrapped in `<dl>` elements
○ARIA IDs are unique
○No form fields have multiple labels
○`<frame>` or `<iframe>` elements have a title
○Heading elements appear in a sequentially-descending order
○`<html>` element has a valid value for its `[lang]` attribute
○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
○Input buttons have discernible text.
○`<input type="image">` elements have `[alt]` text
○Form elements have associated labels
○Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
○List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
○The document does not use `<meta http-equiv="refresh">`
○`<object>` elements have alternate text
○Select elements have associated label elements.
○Skip links are focusable.
○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
○`[lang]` attributes have a valid value
○`<video>` elements contain a `<track>` element with `[kind="captions"]`
○Tables have different content in the summary attribute and `<caption>`.
○All heading elements contain content.
○Uses ARIA roles only on compatible elements
○Image elements do not have `[alt]` attributes that are redundant text.
○Elements with visible text labels have matching accessible names.
○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
○`<td>` elements in a large `<table>` have one or more table headers.
B
Heading Hierarchy
No headings
REVIEW
No headings
Warning::
No headings found
Headings (H1-H6) create the document outline for screen reader navigation.

No headings found

Headings create the document outline for screen reader navigation.

Headings (H1-H6) create the document outline for screen reader navigation.

Why this matters

A page with zero headings is unnavigable by assistive tech and reads as one undifferentiated wall of text.

Learn more ▾

Screen reader users navigate by jumping between H1-H6 elements. A page with no headings has no skip targets — users have to read every word linearly. Adding a heading hierarchy (one H1, then H2 sections, optional H3 subsections) makes the page skimmable for both AT and human readers.

Source: WCAG 1.3.1 / W3C WAI

B
Alt Text Quality
1 of 72 images have issues
REVIEW
1 of 72 images have issues
Critical::
1 image(s) missing alt attribute
Images without alt text are invisible to screen readers.
Critical::
1 image-in-link without alt text
An image inside a link with no alt creates an empty link.
Info::
70 decorative image(s) correctly marked
Info::
1 image(s) with good alt text
72 images 1 good alt text 70 decorative 1 missing
IssueCount
missing1 image(s)

Images without alt text are invisible to screen readers.

Why this matters

Each image without alt text is a WCAG 1.1.1 failure — invisible to screen-reader users, lost from Google Image Search.

Learn more ▾

WCAG 2.1 Level A requires text alternatives for non-decorative images. Empty alt='' is fine for decorative; meaningful images need descriptive text. Common fixes: CMS audit + bulk add, build-time linter (alt-text-required ESLint rule), CI gate on Lighthouse a11y score.

Source: WCAG 2.1 SC 1.1.1 / WebAIM Million Report

An image inside a link with no alt creates an empty link.

Why this matters

Image-only links with no alt create empty links — screen-reader users hear 'link' with no destination context.

Learn more ▾

An <a><img></a> with no img alt is the worst-case for accessibility: AT announces the link but can't describe where it goes. Either add alt to the image OR add aria-label to the link.

Source: WCAG 2.1 SC 2.4.4

B
Form Accessibility
2 of 2 controls have issues
REVIEW
2 of 2 controls have issues
Critical::
1 control(s) without accessible label
Form controls need a <label>, aria-label, or aria-labelledby for screen readers.
Got: <input type="button" id="searchOk">
Warning::
1 control(s) rely on placeholder only
Placeholder text disappears on focus and is not a reliable label.
Got: <input type="text" id="searchKeyword">
2 controls
0 labeled
1 placeholder only
1 unlabeled
ControlTypeLabelMethod
#searchKeywordtext(Search...)placeholder only
#searchOkbutton(none)none

Form controls need a <label>, aria-label, or aria-labelledby for screen readers.

<input type="button" id="searchOk">

Why this matters

Form controls without labels — assistive tech announces 'edit text' with no context; users can't complete forms.

Source: WCAG 2.1 SC 3.3.2

Placeholder text disappears on focus and is not a reliable label.

<input type="text" id="searchKeyword">

Why this matters

Placeholder-only labels disappear when the user starts typing — they must remember what the field was for.

Learn more ▾

Placeholders are NOT labels. They vanish on input, fail color contrast checks (most are gray), and don't satisfy WCAG SC 3.3.2. Always use a real <label> alongside (or aria-labelledby).

Source: WCAG 2.1 SC 3.3.2 / Nielsen Norman

C
Favicon & Branding
Action
4 icon(s) detected
REVIEW
4 icon(s) detected
Info::
favicon.ico present at site root
Info::
HTML icon links detected
Info::
Apple touch icon present
✓ favicon.ico Present
✓ PNG Icons Present
✓ Apple Touch Present
✗ SVG Favicon Missing
✗ Manifest Icons Missing
✗ Multiple Sizes Missing
C
Color Contrast (Screenshot)
Action
20 text elements analyzed, 8 fail WCAG AA
REVIEW

Analyzes text contrast against the actual rendered page, including background images, gradients, and overlays that CSS-based tools cannot detect.

12 pass 8 fail WCAG AA 1 pass AA only
title 北京大学
1.20:1
#000000
on
#011546
needs 4.5:1 (normal text)
16px · top of page (header area)
div 请输入关键字
1.50:1
#000000
on
#012278
needs 4.5:1 (normal text)
16px · top of page (header area)
button 确定
1.77:1
#000000
on
#072C8F
needs 4.5:1 (normal text)
16px · top of page (header area)
a 教职工
2.10:1
#000000
on
#224178
needs 4.5:1 (normal text)
16px · above the fold · over background image/gradient
a 校友
1.10:1
#000000
on
#010F28
needs 4.5:1 (normal text)
16px · above the fold
a 邮箱
3.55:1
#000000
on
#BB2E34
needs 4.5:1 (normal text)
16px · above the fold
a 燕云直播
3.31:1
#000000
on
#B22D2E
needs 4.5:1 (normal text)
16px · above the fold
a 图书馆
3.51:1
#000000
on
#BA2D35
needs 4.5:1 (normal text)
16px · mid-page

1 contrast failures on background images/gradients

These failures are invisible to CSS-based accessibility tools like Lighthouse. The text may be fine on a solid background, but fails when rendered over an image or gradient.

Show all checked elements (20)
ElementRatioRequiredFGBGResult
title 北京大学1.20:14.5:1
#000000
#011546
Fail
div 请输入关键字1.50:14.5:1
#000000
#012278
Fail
button 确定1.77:14.5:1
#000000
#072C8F
Fail
a 学生4.50:14.5:1
#000000
#0976CF
Pass
a 教职工2.10:14.5:1
#000000
#224178
Fail
a 校友1.10:14.5:1
#000000
#010F28
Fail
a 访客17.74:14.5:1
#000000
#EFEBEA
Pass
a 招聘17.74:14.5:1
#000000
#EFEBEA
Pass
a 捐赠17.74:14.5:1
#000000
#EFEBEA
Pass
a 门户17.74:14.5:1
#000000
#EFEBEA
Pass
a 网络17.74:14.5:1
#000000
#EFEBEA
Pass
a 邮箱3.55:14.5:1
#000000
#BB2E34
Fail
a 燕云直播3.31:14.5:1
#000000
#B22D2E
Fail
a 图书馆3.51:14.5:1
#000000
#BA2D35
Fail
a 医学部9.46:14.5:1
#000000
#DB9F9E
Pass
a 领导信箱17.74:14.5:1
#000000
#EFEBEA
Pass
a 北大概况17.74:14.5:1
#000000
#EFEBEA
Pass
a 招生17.74:14.5:1
#000000
#EFEBEA
Pass
a 学部与院系17.74:14.5:1
#000000
#EFEBEA
Pass
a 教育教学17.74:14.5:1
#000000
#EFEBEA
Pass

Methodology: The top 20 text elements by font size were checked. Background color was sampled from the desktop screenshot using a 5-point pattern. WCAG 2.1 AA requires 4.5:1 for normal text and 3:1 for large text.

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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