Jquery 高亮显示文本中重要的关键字

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<li><a class="d1" href="#">Summary</a></li>
<li><a class="d2" href="#">Avatar</a></li>
<li><a class="d3" href="#">Formats</a></li>
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<h2>
Avatar (2009 film)</h2>
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<img src="images/avatar.jpg" alt="Avatar poster" />
<p>
Avatar, also known as James Cameron's Avatar, is an American 3-D science fiction
epic film written and directed by <a href="http://en.wikipedia.org/wiki/James_Cameron">
James Cameron</a>, and was released on December 16, 2009 by 20th Century Fox.
The film is co-produced by <a href="http://en.wikipedia.org/wiki/Lightstorm_Entertainment">
Lightstorm Entertainment</a>, and <span class="d1">focuses on an epic conflict on Pandora</span>,
an inhabited Earth-sized moon of Polyphemus, one of three fictional gas giants orbiting
<a href="http://en.wikipedia.org/wiki/Alpha_Centauri_A">Alpha Centauri A</a>. On
Pandora, human colonists and the sentient humanoid indigenous inhabitants of Pandora,
the Na'vi, engage in a war over the planet's resources and the latter's continued
existence. The film's title refers to <span class="d2">an avatar, a representation of
a real person in a virtual world</span>.</p>
<p>
<span class="d3">The film was released in 2D and 3D formats</span>, along with an
IMAX 3D release in selected theaters. The film is being touted as a breakthrough
in terms of filmmaking technology, for its development of 3D viewing and stereoscopic
filmmaking with cameras that were specially designed for the film's production.</p>
<p>
Read the rest of the <a href="http://en.wikipedia.org/wiki/Avatar_(2009_film)">original
Wikipedia page about Avatar</a></p>
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{
position: relative;
}
.entity-source .mask
{
display: none;
position: absolute;
top: 0;
left: 0;
height: 100%;
width: 100%;
z-index: 1;
}
.entity-source span
{
z-index: 2;
}
.entity-source span.show
{
background: #ffc;
color: #000;
}

jQuery(document).ready(function($) {
// mask source 控制mask的动画效果
var maskSource = jQuery('.mask');
jQuery('.entity-results').hover(function() {
maskSource.animate({opacity:0.7},1).fadeIn('750');
}, function() {
maskSource.fadeOut('1000');
});
// match hover 控制段落的高亮显示
var sample1 = jQuery('span.d1');
var sample2 = jQuery('span.d2');
var sample3 = jQuery('span.d3');
jQuery('a.d1').hover(function() {
sample1.addClass('show'); //给段落添加类
}, function() {
sample1.removeClass('show'); //移除段落类
});
jQuery('a.d2').hover(function() {
sample2.addClass('show');
}, function() {
sample2.removeClass('show');
});
jQuery('a.d3').hover(function() {
sample3.addClass('show');
}, function() {
sample3.removeClass('show');
});
});