#sw-update {
  position: fixed; left: 16px; bottom: 16px; z-index: 50;
  font: 500 13px/1.3 var(--ui, system-ui, sans-serif);
  color: var(--ink, #1C2033); background: var(--panel, #fff);
  border: 1px solid var(--line-strong, #D2D1C8); border-radius: 6px;
  padding: 8px 12px; cursor: pointer;
}
#sw-update:hover { border-color: var(--act, #2E44D6); }
#sw-update:focus-visible { outline: 2px solid var(--act, #2E44D6); outline-offset: 2px; }