function collapse () {
document.getElementById("neboshCourses").style.display = 'none';
document.getElementById("neboshDiploma").style.display = 'none';
document.getElementById("ioshCourses").style.display = 'none';
document.getElementById("schoolsCourses").style.display = 'none';
document.getElementById("safety").style.display = 'none';
document.getElementById("construction").style.display = 'none';
document.getElementById("partners").style.display = 'none';
}
function showChild(child) {
document.getElementById("neboshCourses").style.display = 'none';
document.getElementById("neboshDiploma").style.display = 'none';
document.getElementById("ioshCourses").style.display = 'none';
document.getElementById("schoolsCourses").style.display = 'none';
document.getElementById("safety").style.display = 'none'; 
document.getElementById("construction").style.display = 'none';
document.getElementById("partners").style.display = 'none';
document.getElementById(""+child+"").style.display = 'block';
}
function show2ndChild (child) {
document.getElementById(""+child+"").style.display = 'block';
}
function collapse2ndChild (child) {
document.getElementById(""+child+"").style.display = 'none';
}