body:after { z-index: 65535; display: block; content: '検証環境'; position: fixed; top: 10px; right: 20px; border: 7px solid red; color: red; border-radius: 15px; padding: 2px 20px; line-height: 1; font-weight: bold; font-size: 70px; transition: all 500ms cubic-bezier(0.040, 0.730, 0.530, 1.310); transition-delay: 5s; transform: rotate(5deg); transform-origin: left bottom; } body:hover:after { transition-delay: 0s; top: -2em; }