I’ve reported this issue to dev team, they will fix and update in the next release of this JA Argo template.
At this mean time, you can apply my suggestion into your site:
+ Open templates/ja_argo/css/custom.css file
+ Add new script
.head-search .input,
.head-search .inputbox {
background: url(../images/ico/search.png) no-repeat 8px center;
border: none;
-webkit-box-shadow: none;
-moz-box-shadow: none;
box-shadow: none;
height: 25px;
line-height: 25px;
display: inline-block;
width: 20px;
text-indent: 26px;
}
.head-search .input:hover,
.head-search .input:active,
.head-search .input:focus,
.head-search .inputbox:hover,
.head-search .inputbox:active,
.head-search .inputbox:focus {
-webkit-box-shadow: none;
-moz-box-shadow: none;
box-shadow: none;
}
.head-search .input:focus,
.head-search .inputbox:focus {
color: #fff;
width: 180px;
}
.head-search br {
display: none;
}
Hope it helps.