Keycap

<button class="btn-sig-keycap" type="button">
  <span class="btn-sig-keycap__cap">
    <span>Enter</span>
    <span class="btn-sig-keycap__legend" aria-hidden="true">↵</span>
  </span>
</button>

.btn-sig-keycap {
  --btn-bg: #e9e4d8;
  --btn-fg: #26252c;
  --btn-font: ui-monospace, monospace;
  --btn-size: 15px;
  --btn-weight: 600;
  --btn-px: 22px;
  --btn-py: 11px;
  --btn-w: auto;
  --btn-h: auto;
  --btn-bw: 0px;
  --btn-line: #8b6cff;
  --btn-radius: 8px;
  --btn-speed: 180ms;
}

.btn-sig-keycap {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5em;
  box-sizing: border-box;
  width: var(--btn-w);
  height: var(--btn-h);
  padding: 5px 8px 11px;
  font-family: var(--btn-font);
  font-size: var(--btn-size);
  font-weight: var(--btn-weight);
  line-height: 1.2;
  color: var(--btn-fg);
  background: linear-gradient(180deg, color-mix(in srgb, var(--btn-bg) 72%, #000), color-mix(in srgb, var(--btn-bg) 50%, #000));
  border: var(--btn-bw) solid var(--btn-line);
  border-radius: calc(var(--btn-radius) + 4px);
  box-shadow: 0 6px 0 rgba(0,0,0,.5), 0 12px 18px rgba(0,0,0,.4);
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition: all var(--btn-speed) ease;
}

.btn-sig-keycap:focus-visible {
  outline: 2px solid var(--btn-bg);
  outline-offset: 2px;
}

.btn-sig-keycap:disabled {
  opacity: 0.5;
  pointer-events: none;
}

.btn-sig-keycap__icon {
  width: 1.15em;
  height: 1.15em;
  flex-shrink: 0;
}

.btn-sig-keycap:hover {
  transform: translateY(1px);
  box-shadow: 0 5px 0 rgba(0,0,0,.5), 0 10px 16px rgba(0,0,0,.4);
}

.btn-sig-keycap__cap {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: var(--btn-py) var(--btn-px);
  background: linear-gradient(165deg, color-mix(in srgb, var(--btn-bg) 86%, #fff), var(--btn-bg));
  border-radius: var(--btn-radius);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.55), inset 0 -3px 4px rgba(0,0,0,.14);
}

.btn-sig-keycap__legend {
  font-size: 0.85em;
  opacity: 0.55;
}

.btn-sig-keycap:active {
  transform: translateY(5px);
  box-shadow: 0 1px 0 rgba(0,0,0,.5), 0 3px 6px rgba(0,0,0,.4);
}

@media (prefers-reduced-motion: reduce) {
  .btn-sig-keycap {
    animation: none !important;
    transition: none !important;
  }
}

// No JavaScript needed: this one is CSS only.

import type React from "react";
import "./sig-keycap.css"; // the CSS tab

export function BtnSigKeycap({ children = "Enter", ...props }: React.ComponentProps<"button">) {
  return (
    <button className="btn-sig-keycap" type="button" {...props}>
      <span className="btn-sig-keycap__cap">
        <span>{children}</span>
        <span className="btn-sig-keycap__legend" aria-hidden="true">{"↵"}</span>
      </span>
    </button>
  );
}

<button class="relative inline-flex items-center justify-center gap-[0.5em] [box-sizing:border-box] [padding:5px_8px_11px] [font-family:ui-monospace,_monospace] text-[15px] font-[600] [line-height:1.2] text-[#26252c] [background:linear-gradient(180deg,_color-mix(in_srgb,_#e9e4d8_72%,_#000),_color-mix(in_srgb,_#e9e4d8_50%,_#000))] [border:0px_solid_#8b6cff] rounded-[calc(8px_+_4px)] [box-shadow:0_6px_0_rgba(0,0,0,.5),_0_12px_18px_rgba(0,0,0,.4)] cursor-pointer no-underline whitespace-nowrap [transition:all_180ms_ease] focus-visible:[outline:2px_solid_#e9e4d8] focus-visible:[outline-offset:2px] disabled:[opacity:0.5] disabled:[pointer-events:none] hover:[transform:translateY(1px)] hover:[box-shadow:0_5px_0_rgba(0,0,0,.5),_0_10px_16px_rgba(0,0,0,.4)] active:[transform:translateY(5px)] active:[box-shadow:0_1px_0_rgba(0,0,0,.5),_0_3px_6px_rgba(0,0,0,.4)] motion-reduce:[transition:none!important]" type="button">
  <span class="inline-flex items-center gap-[14px] [padding:11px_22px] [background:linear-gradient(165deg,_color-mix(in_srgb,_#e9e4d8_86%,_#fff),_#e9e4d8)] rounded-[8px] [box-shadow:inset_0_1px_0_rgba(255,255,255,.55),_inset_0_-3px_4px_rgba(0,0,0,.14)]">
    <span>Enter</span>
    <span class="text-[0.85em] [opacity:0.55]" aria-hidden="true">↵</span>
  </span>
</button>