enric01 Try add this to override.css file
#gkHeaderNav .gkMainMenu .gkmenu > li div.childcontent{overflow: visible !important;}
The CSS Override option, when enabled in template --> advanced settings , will take CSS rules entered into a special override.css file and, like the Custom CSS Code field, will apply them after the other stylesheets.
Kindly ensure to clear your browser cache if changes dont reflect
