absolute-non-replaced-height-010.xht (2426B)
1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 2 <html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <title>CSS Test: Absolutely positioned, non-replaced elements, 'margin-top' and 'margin-bottom' set to '0'</title> 5 <link rel="author" title="Microsoft" href="http://www.microsoft.com/" /> 6 <link rel="reviewer" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/" /> <!-- 2012-08-31 --> 7 <link rel="help" href="http://www.w3.org/TR/CSS21/visudet.html#abs-non-replaced-height" /> 8 <link rel="match" href="absolute-non-replaced-height-003-ref.xht" /> 9 10 <meta name="assert" content="The 'auto' values for 'margin-top' and 'margin-bottom' are set to '0', when 'top' is 'auto' and 'height' and 'bottom' are not 'auto'." /> 11 <style type="text/css"> 12 #div1 13 { 14 border: solid black; 15 height: 3in; 16 position: relative; 17 width: 3in; 18 } 19 div div 20 { 21 background: blue; 22 bottom: 1in; 23 height: 1in; 24 margin-bottom: auto; 25 margin-top: auto; 26 position: absolute; 27 top: auto; 28 width: 100%; 29 } 30 31 /* 32 33 auto (to solve) : top 34 + 35 auto (to solve): margin-top 36 + 37 0 : border-top-width 38 + 39 0 : padding-top 40 + 41 1in : height 42 + 43 0 : padding-bottom 44 + 45 0 : border-bottom-width 46 + 47 auto (to solve): margin-bottom 48 + 49 1in : bottom 50 ============= 51 3in : height of containing block 52 53 54 " 55 'top' is 'auto', 'height' and 'bottom' are not 'auto', 56 then set 'auto' values for 'margin-top' and 'margin-bottom' to 0, 57 and solve for 'top' 58 " 59 60 so this brings: 61 62 auto (to solve) : top 63 + 64 0 (set): margin-top 65 + 66 0 : border-top-width 67 + 68 0 : padding-top 69 + 70 1in : height 71 + 72 0 : padding-bottom 73 + 74 0 : border-bottom-width 75 + 76 0 (set): margin-bottom 77 + 78 1in : bottom 79 ============= 80 3in : height of containing block 81 82 So, top must use 1in in order to balance the equation 83 84 85 */ 86 87 </style> 88 </head> 89 <body> 90 <p>Test passes if a blue rectangle is <strong>vertically centered</strong> in an hollow black square.</p> 91 <div id="div1"> 92 <div></div> 93 </div> 94 </body> 95 </html>