html{scroll-behavior:smooth}.card{border-radius:1rem;transition:transform 0.25s,box-shadow 0.25s}.card:hover{transform:translateY(-4px)}.err-code{font-size:clamp(5rem,15vw,10rem);font-weight:900;line-height:1;letter-spacing:-0.03em}.back-top{position:fixed;bottom:1.5rem;right:1.5rem;z-index:999;border-radius:50%;width:3rem;height:3rem;display:flex;align-items:center;justify-content:center;padding:0}