const neededUsername = "1";
const neededPassword = "11";

function verify() {
    var username = document.getElementById("username").value;
    var password = document.getElementById("password").value;
    if (username == neededUsername && password == neededPassword) {
        top.location = "index.html";
    }
    else {
        alert(`Нямате право на достъп.`);
    }
}

//---------------------------------------------------------------------------------------------------------------------//
function changeOptionColor() {
    if (document.getElementById("subscription").selectedIndex == "0") {
        document.getElementById("yes").style.backgroundColor = "green";
		alert("Да - правилен отговор!");
    }
    else {
		if (document.getElementById("subscription").selectedIndex == "2") {
        document.getElementById("no").style.backgroundColor = "red";
		alert("Вашият избор: Не");
		}
		else if (document.getElementById("subscription").selectedIndex == "1") {
        document.getElementById("maybe").style.backgroundColor = "red";
		alert("Вашият избор: Може би");
		}
	}
}

//--------------------------------------------------------------------------------------------------------------------//
function dropdown(sublink_id, triangle_id){
    if(document.getElementById(sublink_id).style.display === ""){
        document.getElementById(triangle_id).style.transform = "rotate(180deg)"
        document.getElementById(sublink_id).style.display = "block";
    }
    else{
        document.getElementById(triangle_id).style.transform = "rotate(90deg)"
        document.getElementById(sublink_id).style.display = "";
    }
}
//----------------------------------------------------------------------------------------------------------------//
var images = [], currentImg = 0;
images[0] = "../photos/photo-9.jpg";
images[1] = "../photos/photo-8.jpg";
images[2] = "../photos/photo-12.jpg";

function nextImage(){
    currentImg = currentImg >= images.length - 1 ? 0 : ++currentImg;
    document.getElementById("switching-img").src = images[currentImg];
}

function previousImage(){
    currentImg = currentImg <= 0 ? images.length - 1 : --currentImg;
    document.getElementById("switching-img").src = images[currentImg];
}

setInterval(nextImage, 3000);