deep clone doesn't work

gistfile1.txt

const a = [1,2,3,4,5];
const aCloned = [...a];

aCloned.push(7);
console.log(a);
console.log(aCloned);

ref = {big: 'name'};
skills = ["javascript"]

const o = { name: "john", lastname: "nelson", skills: skills, total: {first: ref} };
const oCloned = { ...o };

ref.big = "what"
o.skills.push('php')
oCloned.rancher = true;

console.log(o);
console.log(oCloned);