//Si el Explorador es...

//Firefox 2
if (navigator.userAgent.toLowerCase().indexOf('firefox/2') > -1)
document.write('<style type="text/css"> \
a, span, img {display:-moz-inline-box;} \
.TB_overlayBG {-moz-opacity:0.75;} \
#TB_HideSelect {-moz-opacity:0;} \
</style>');

//Internet Explorer 6
if (navigator.userAgent.toLowerCase().indexOf('ie 6') > -1)
document.write('<style type="text/css"> \
.IMAGEN-PNG {background-image: none; filter: none !important; filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\'css/general/IMAGEN-PNG.png\')} \
a {color:expression(this.parentNode.currentStyle.color);} \
* html #TB_overlay {position:absolute; height:expression(document.body.scrollHeight > document.body.offsetHeight ? document.body.scrollHeight : document.body.offsetHeight + "px");} \
* html #TB_window {position:absolute; margin-top:expression(0 - parseInt(this.offsetHeight / 2) + (TBWindowMargin = document.documentElement && document.documentElement.scrollTop || document.body.scrollTop) + "px");} \
* html #TB_load {position:absolute; margin-top: expression(0 - parseInt(this.offsetHeight / 2) + (TBWindowMargin = document.documentElement && document.documentElement.scrollTop || document.body.scrollTop) + "px");} \
* html #TB_HideSelect {position:absolute; height:expression(document.body.scrollHeight > document.body.offsetHeight ? document.body.scrollHeight : document.body.offsetHeight + "px");} \
#TB_iframeContent {margin-bottom:1px;} \
.TB_overlayBG {filter:alpha(opacity=75);} \
#TB_HideSelect {filter:alpha(opacity=0);} \
</style>');

//Internet Explorer 7
if (navigator.userAgent.toLowerCase().indexOf('ie 7') > -1)
document.write('<style type="text/css"> \
a {color:expression(this.parentNode.currentStyle.color);} \
.TB_overlayBG {filter:alpha(opacity=75);} \
#TB_HideSelect {filter:alpha(opacity=0);} \
</style>');

//Safari
if (navigator.userAgent.toLowerCase().indexOf('safari') > -1)
document.write('<style type="text/css"> \
textarea {resize:none;} \
</style>');

//Google Chrome
if (navigator.userAgent.toLowerCase().indexOf('chrome') > -1)
document.write('<style type="text/css"> \
textarea {resize:none;} \
</style>');

//Opera
if (navigator.userAgent.toLowerCase().indexOf('opera') > -1)
document.write('<style type="text/css"> \
\
</style>');