当悬停元素位于单独的div中时，如何仍可以更改其他元素的样式？

Question

I understand that an element can change the style of associated elements upon hovering as long as they're within the same divs, but how can the same functionality be achieved when they're all in separate elements such as div , section , article , h1 , etc.

I have set up a jsfiddle that consists of a version that works and a version that doesn't. As best, I would like to find out a way to achieve this through CSS only, but if it is an issue that only javascript can solve, that'll be okay.

I've been looking around StackOverflow but there doesn't seem to be an answer to what to do when the elements are within separate elements.

HTML

<h1>This version works fine...</h1>
... <span class="a1">fruits</span> and <span class="b1">vegetables</span>... <span class="a2">apple</span>, <span class="b2">asparagus</span>

<h1>...but how can I get this to work?</h1>
... <div class="div1"><span class="a1">fruits</span> and <span class="b1">vegetables</span></div>... <div class="div2"><span class="a2">apple</span>, <span class="b2">asparagus</span></div>

CSS

.a1, .b1 {
    border:1px solid #333333;
    padding: 0 1% 0 1%;
    text-align: center;
    -o-transition: color 0.2s ease-out;
    -ms-transition: color 0.2s ease-out;
    -moz-transition: color 0.2s ease-out;
    -webkit-transition: color 0.2s ease-out;
    transition: color 0.2s ease-out;
}
.a2, .b2 {
    border:1px solid #dddddd;
    padding: 0 1% 0 1%;
    text-align: center;
    -o-transition: color 0.2s ease-out;
    -ms-transition: color 0.2s ease-out;
    -moz-transition: color 0.2s ease-out;
    -webkit-transition: color 0.2s ease-out;
    transition: color 0.2s ease-out;
}
.a1:hover {
    border:1px solid red;
    color: white;
    background-color: red;
}
.b1:hover {
    border:1px solid green;
    color: white;
    background-color: green;
}
.a1:hover ~ .a2 {
    border:1px solid red;
    color: white;
    background-color: red;
}
.b1:hover ~ .b2 {
    border:1px solid green;
    color: white;
    background-color: green;
}

Answer 1

I've found out what the problem is.

Go to your code, fix or take off the lines below from the problematic part

</div>
<div class="div2">

Two problems

1. 1 Closing DIV without a starting part
2. 1 Opening DIV without closing part

See it working here

For jQuery: you can do something like

 $(".a1").hover(function () {
                 $(".a2, .a1").css({"color":"white", "background-color":"red"});
    });

See the jQuery example here

Note: If you have the DIV's there for a reason, try the jQuery method

Answer 2

CSS

.a1:hover, .a2.light { /* your css */ }
.b1:hover, .b2.light { /* your css */ }

JAVASCRIPT

var fruits = document.querySelectorAll('.div2 .a2'),
    vegets = document.querySelectorAll('.div2 .b2'),
    spanf = document.querySelector('.div1 .a1'),
    spanv = document.querySelector('.div1 .b1');

spanf.addEventListener('mouseenter', function() {
    [].forEach.call(fruits, function(el) {
        el.classList.add('light');
    });
});
spanf.addEventListener('mouseleave', function() {
    [].forEach.call(fruits, function(el) {
        el.classList.remove('light');
    });
});

spanv.addEventListener('mouseenter', function() {
    [].forEach.call(vegets, function(el) {
        el.classList.add('light');
    });
});
spanv.addEventListener('mouseleave', function() {
    [].forEach.call(vegets, function(el) {
        el.classList.remove('light');
    });
});

DEMO

NOTE Safari doesn't support mouseenter / mouseleave . You can use mouseover / mouseout instead.

If you prefer a solution with jQUERY (it's less to write, but does the same under the hood):

var fruits = $('.div2 .a2'),
    vegets = $('.div2 .b2');

$('.div1 .a1').hover(function() {fruits.toggleClass('light');});

$('.div1 .b1').hover(function() {vegets.toggleClass('light');});