const ITEMS = [...document.querySelectorAll('.item')].map(c => ({ _el: c })),
_STYL = document.createElement('style');

ITEMS.forEach((c, i) => {
  c._view = c._el.querySelector('.view');
  c._code = c._el.querySelector('.code');
  c.ctext = c._code.textContent;
  c._view.id = `v${i}`;
});

_STYL.textContent = ITEMS.map((c, i) => `#v${i} { ${c.ctext} }`).join('');
document.body.appendChild(_STYL);