help with styling the FAQ toggle please

Hi,

I’d like to restyle the FAQ toggle elements but can’t get the css to work. Could you help with the correct selectors to use? I’d like to:
1. change the panel border colour
2. change the header background colour
3. make the body background clour transparent

The code I’ve tried as a test is this:

#panel {
 border-color: #dd5858 !important;
}
#panel .panel-heading {
 background-color:#6ebad3 !important;
}
#panel .panel-body {
 background-color: clear !important;
}

Many thanks.