function btn_home_mouseover() {
    document.getElementById("btn_home").src = "images/home_button_orange.jpg";
}
function btn_home_mouseout() {
    document.getElementById("btn_home").src = "images/home_button_grey.jpg";
}

function btn_company_mouseover() {
    document.getElementById("btn_company").src = "images/company_button_orange.jpg";
}
function btn_company_mouseout() {
    document.getElementById("btn_company").src = "images/company_button_grey.jpg";
}

function btn_services_mouseover() {
    document.getElementById("btn_services").src = "images/services_button_orange.jpg";
}
function btn_services_mouseout() {
    document.getElementById("btn_services").src = "images/services_button_grey.jpg";
}

function btn_technology_mouseover() {
    document.getElementById("btn_technology").src = "images/technology_button_orange.jpg";
}
function btn_technology_mouseout() {
    document.getElementById("btn_technology").src = "images/technology_button_grey.jpg";
}