The following iframe has the css declarations:
border: 4px solid green; padding: 32px; background-color: yellow;
onfocus="this.style.MozOutline = '4px dotted black'; this.style.outline = '4px dotted blue'; this.style.borderColor = 'red'; this.contentWindow.document.documentElement.style.border = '4px solid purple';
onblur="this.style.MozOutline = '0px none red'; this.style.outline = '0px none purple'; this.style.borderColor = 'green'; this.contentWindow.document.documentElement.style.border = '0px dashed gray';