$(document).ready(function () {
    //$("#flash").css('height', ($(window).height()));
	if ($(window).height() > 700) {
        $("#flash").css('height', ($(window).height()));
    } else {
        $("#flash").css('height', '700px');
    }
});
function doSomething() {    
    if ($(window).height() > 700) {
        $("#flash").css('height', ($(window).height()));
    } else {
        $("#flash").css('height', '700px');
    }
};
var resizeTimer;
$(window).resize(function () {
    clearTimeout(resizeTimer);
    resizeTimer = setTimeout(doSomething, 100);
});