:where(dialog){background-color:#fff;border:1px solid var(--color-line);border-radius:var(--border-radius);box-shadow:var(--shadow);inline-size:calc(100% - var(--size-base) * 2);inset:0;max-block-size:calc(100% - var(--size-base) * 2);max-inline-size:var(--size-content-large);padding:var(--size-base);position:fixed}:where(dialog)::backdrop{-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);background-color:rgba(255,255,255,.8)}:where(dialog)>:first-child{margin-block-start:0}