//音乐开关

var myvideo=document.getElementById('videoBtn');

myvideo.addEventListener('play',function(){

var audio = document.getElementById('bgPlayer');

if(myvideo.paused){

audio.play();

$(".M-btn").addClass("on")

}else{

audio.pause();

$(".M-btn").removeClass("on")

}

});

myvideo.addEventListener('pause',function(){

var audio = document.getElementById('bgPlayer');

if(myvideo.paused){

audio.play();

$(".M-btn").addClass("on")

}else{

audio.pause();

$(".M-btn").removeClass("on")

}

});