iframe[data-dospectrum-wxchat][data-wxchat-mobile=false]{max-width:calc(100vw - 48px);max-height:calc(100dvh - 48px)}iframe[data-dospectrum-wxchat][data-wxchat-mobile=true]{max-width:100vw;max-height:100dvh}html[data-wxchat-ready=true] [data-back-to-top]{bottom:calc(96px + env(safe-area-inset-bottom,0px))}[data-wxchat-fallback]+[data-back-to-top]{bottom:calc(88px + env(safe-area-inset-bottom,0px))}body:has([data-wxchat-fallback]) [data-back-to-top]{bottom:calc(88px + env(safe-area-inset-bottom,0px))}