.line-under:before{content:"";position:absolute;left:-100%;top:0;height:100%;width:100%;background:#a1887f;transition:left .4s ease}input:focus+.line-under:before,textarea:focus+.line-under:before{left:0}textarea{background:transparent;border:3px solid #a1887f;color:#000;border-radius:15px;font-weight:700;margin-top:20px;padding:15px}@keyframes shake{0%{transform:translateX(0)}20%{transform:translateX(-5px)}40%{transform:translateX(5px)}60%{transform:translateX(-5px)}80%{transform:translateX(5px)}to{transform:translateX(0)}}.input-error{animation:shake .3s ease-in-out}