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html - How to remove/ignore :hover css style on touch devices

I want to ignore all :hover CSS declarations if a user visits our website via touch device. Because the :hover CSS does not make sense, and it can even be disturbing if a tablet triggers it on click/tap because then it might stick until the element loses focus. To be honest, I don't know why touch devices feel the need to trigger :hover in first place - but this is reality, so this problem is reality as well.

a:hover {
   color:blue;
   border-color:green;
   // etc. > ignore all at once for touch devices
}

So, (how) can I remove/ignore all CSS :hover declarations at once (without having to know each one) for touch devices after having them declared?

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tl;dr use this: https://jsfiddle.net/57tmy8j3/

If you're interested why or what other options there are, read on.

Quick'n'dirty - remove :hover styles using JS

You can remove all the CSS rules containing :hover using Javascript. This has the advantage of not having to touch CSS and being compatible even with older browsers.

function hasTouch() {
  return 'ontouchstart' in document.documentElement
         || navigator.maxTouchPoints > 0
         || navigator.msMaxTouchPoints > 0;
}

if (hasTouch()) { // remove all the :hover stylesheets
  try { // prevent exception on browsers not supporting DOM styleSheets properly
    for (var si in document.styleSheets) {
      var styleSheet = document.styleSheets[si];
      if (!styleSheet.rules) continue;

      for (var ri = styleSheet.rules.length - 1; ri >= 0; ri--) {
        if (!styleSheet.rules[ri].selectorText) continue;

        if (styleSheet.rules[ri].selectorText.match(':hover')) {
          styleSheet.deleteRule(ri);
        }
      }
    }
  } catch (ex) {}
}

Limitations: stylesheets must be hosted on the same domain (that means no CDNs). Disables hovers on mixed mouse & touch devices like Surface or iPad Pro, which hurts the UX.

CSS-only - use media queries

Place all your :hover rules in a @media block:

@media (hover: hover) {
  a:hover { color: blue; }
}

or alternatively, override all your hover rules (compatible with older browsers):

a:hover { color: blue; }

@media (hover: none) {
  a:hover { color: inherit; }
}

Limitations: works only on iOS 9.0+, Chrome for Android or Android 5.0+ when using WebView. hover: hover breaks hover effects on older browsers, hover: none needs overriding all the previously defined CSS rules. Both are incompatible with mixed mouse & touch devices.

The most robust - detect touch via JS and prepend CSS :hover rules

This method needs prepending all the hover rules with body.hasHover. (or a class name of your choice)

body.hasHover a:hover { color: blue; }

The hasHover class may be added using hasTouch() from the first example:

if (!hasTouch()) document.body.className += ' hasHover'

However, this whould have the same drawbacks with mixed touch devices as previous examples, which brings us to the ultimate solution. Enable hover effects whenever a mouse cursor is moved, disable hover effects whenever a touch is detected.

function watchForHover() {
  // lastTouchTime is used for ignoring emulated mousemove events
  let lastTouchTime = 0

  function enableHover() {
    if (new Date() - lastTouchTime < 500) return
    document.body.classList.add('hasHover')
  }

  function disableHover() {
    document.body.classList.remove('hasHover')
  }

  function updateLastTouchTime() {
    lastTouchTime = new Date()
  }

  document.addEventListener('touchstart', updateLastTouchTime, true)
  document.addEventListener('touchstart', disableHover, true)
  document.addEventListener('mousemove', enableHover, true)

  enableHover()
}

watchForHover()

This should work basically in any browser and enables/disables hover styles as needed.

Here's the full example - modern: https://jsfiddle.net/57tmy8j3/
Legacy (for use with old browsers): https://jsfiddle.net/dkz17jc5/19/


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