В дополнение к ответу Жоао Куньи эта проблема теперь в списке задач Mozilla и предназначена для версии 35.
Для тех, кто хочет, есть обходной путьТодд Паркер, на который ссылается блог Куньи, который работает сегодня:
http://jsfiddle.net/xvushd7x/
HTML:
<label class="wrapper">This label wraps the select
<div class="button custom-select ff-hack">
<select>
<option>Apples</option>
<option>Bananas</option>
<option>Grapes</option>
<option>Oranges</option>
<option>A very long option name to test wrapping</option>
</select>
</div>
</label>
CSS:
/* Label styles: style as needed */
label {
display:block;
margin-top:2em;
font-size: 0.9em;
color:#777;
}
/* Container used for styling the custom select, the buttom class below adds the bg gradient, corners, etc. */
.custom-select {
position: relative;
display:block;
margin-top:0.5em;
padding:0;
}
/* These are the "theme" styles for our button applied via separate button class, style as you like */
.button {
border: 1px solid #bbb;
border-radius: .3em;
box-shadow: 0 1px 0 1px rgba(0,0,0,.04);
background: #f3f3f3; /* Old browsers */
background: -moz-linear-gradient(top, #ffffff 0%, #e5e5e5 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#ffffff), color-stop(100%,#e5e5e5)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #ffffff 0%,#e5e5e5 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #ffffff 0%,#e5e5e5 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #ffffff 0%,#e5e5e5 100%); /* IE10+ */
background: linear-gradient(to bottom, #ffffff 0%,#e5e5e5 100%); /* W3C */
}
/* This is the native select, we're making everything but the text invisible so we can see the button styles in the wrapper */
.custom-select select {
width:100%;
margin:0;
background:none;
border: 1px solid transparent;
outline: none;
/* Prefixed box-sizing rules necessary for older browsers */
-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;
/* Remove select styling */
appearance: none;
-webkit-appearance: none;
/* Font size must the 16px or larger to prevent iOS page zoom on focus */
font-size:16px;
/* General select styles: change as needed */
font-family: helvetica, sans-serif;
font-weight: bold;
color: #444;
padding: .6em 1.9em .5em .8em;
line-height:1.3;
}
/* Custom arrow sits on top of the select - could be an image, SVG, icon font, etc. or the arrow could just baked into the bg image on the select. Note this si a 2x image so it will look bad in browsers that don't support background-size. In production, you'd handle this resolution switch via media query but this is a demo. */
.custom-select::after {
content: "";
position: absolute;
width: 9px;
height: 8px;
top: 50%;
right: 1em;
margin-top:-4px;
background-image: url(http://filamentgroup.com/files/select-arrow.png);
background-repeat: no-repeat;
background-size: 100%;
z-index: 2;
/* These hacks make the select behind the arrow clickable in some browsers */
pointer-events:none;
}
/* Hover style */
.custom-select:hover {
border:1px solid #888;
}
/* Focus style */
.custom-select select:focus {
outline:none;
box-shadow: 0 0 1px 3px rgba(180,222,250, 1);
background-color:transparent;
color: #222;
border:1px solid #aaa;
}
/* Set options to normal weight */
.custom-select option {
font-weight:normal;
}