1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2 <html> 3 <head> 4 <style> 5 body { margin: 0px; } 6 .outer { 7 margin: -100px; 8 width: 400px; 9 height: 500px; 10 background-color: green; 11 } 12 .outer:hover { 13 background-color: red; 14 } 15 .inner { 16 visibility: hidden; 17 width: 100%; 18 height: 50%; 19 background-color: cyan; 20 } 21 </style> 22 </head> 23 24 <body> 25 <div class="outer" 26 onmouseover="firstChild.style.visibility='visible'" 27 onmouseout="firstChild.style.visibility='hidden'"><div class="inner"></div></div> 28 </body> 29 </html> 30
