let pars = document.getElementsByTagName("p");
undefined
pars
HTMLCollection(15) [p, p, p, p, p, p, p, p, p, p, p, p, p, p, p]
pars[0].style.color="red";
'red'
pars[0].style.backgroundColor="#FFFF00";
'#FFFF00'
pars[0] = 5
5
pars
HTMLCollection(15) [p, p, p, p, p, p, p, p, p, p, p, p, p, p, p]
pars[0]
<p style=​"color:​ red;​ background-color:​ rgb(255, 255, 0)​;​">​blah​</p>​
pars[1].style.fontSize=48
48
pars[1].style.fontSize="48px"
'48px'
for(let k = 0; k < pars.length; k++)
{
    pars[k].style.display="none";
}
'none'
for(let k = 0; k < pars.length; k++)
{
    pars[k].style.display="block";
}
'block'
for(item k of pars)
VM850:1 Uncaught SyntaxError: Unexpected identifier
for(let k of pars){k.display = "inline";}
'inline'
for(let k of pars){k.style.display = "inline";}
'inline'