.flicking{animation:flicker-bg 1.2s infinite alternate}@keyframes flicker-bg{0%{background-color:#90ee90}50%{background-color:#4cd964}to{background-color:#90ee90}}.hinting{animation:hint-bg 1s infinite alternate}@keyframes hint-bg{0%{background-color:#ffd59a}50%{background-color:#ffb347}to{background-color:#ffd59a}}