Accessibility ≠ Overlay: semantic HTML, the foundation an overlay cannot replace
A site can look perfectly organised and still be confusing to someone using a screen reader, keyboard or other assistive technology. The reason may be invisible: HTML. Elements such as <main>, <nav>, <button>, <label> and headings carry meaning, not just appearance.
Semantics communicate what each thing is
Two pieces of text can look identical but mean different things to the browser. An <h2> identifies a section; a CSS-enlarged <p> remains a paragraph. W3C explains that well-marked structure supports navigation and orientation.
Headings and regions are navigation
Headings communicate content organisation. Elements such as <header>, <nav>, <main>, <aside> and <footer> identify regions that screen readers and other tools can use for efficient navigation.
A button should be a button
A native <button> already provides known semantics and behaviour. Recreating one with a <div> means rebuilding semantics, focus and keyboard behaviour. The first rule of ARIA recommends native HTML when an appropriate element exists.
Forms need real relationships
Visually placing “Email” beside a field is not enough. W3C recommends associating labels with controls, normally with <label>, so assistive technologies can identify the field purpose.
ARIA complements; it does not replace correct HTML
ARIA is essential when native HTML cannot provide required semantics, especially in complex interfaces. It is not intended to replace correct HTML unnecessarily, and incorrect ARIA can alter the semantics exposed to assistive technology.
What an overlay finds when it arrives late
A layer running after page load acts on a structure that already exists. If the base contains incorrect elements, missing relationships or poorly built custom components, the problem began before the overlay. Building correctly at source and testing with assistive technology is more robust.
What about Blind Reader?
Blind Reader belongs on the user-assistance side. Assistive technology can facilitate access or interaction, but the site still needs understandable structure. Blind Reader helps the user; it does not replace semantic HTML or certify the site.
Build it well before adding layers
Semantics are not an invisible technical detail; they are part of the user experience. Before adding a layer that interprets or transforms the page, use the right element for each function. Accessibility starts in the code.
Fuentes / Sources
W3C WAI — Page Structure Tutorial
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