Options
BlockUI's default options look (exactly) like this: 
// override these in your code to change the default behavior and style  
$.blockUI.defaults = {  
    // message displayed when blocking (use null for no message)  
    message:  '<h1>Please wait...</h1>',  
  
    // styles for the message when blocking; if you wish to disable  
    // these and use an external stylesheet then do this in your code:  
    // $.blockUI.defaults.css = {};  
    css: {  
        padding:        0,  
        margin:         0,  
        width:          '30%',  
        top:            '40%',  
        left:           '35%',  
        textAlign:      'center',  
        color:          '#000',  
        border:         '3px solid #aaa',  
        backgroundColor:'#fff',  
        cursor:         'wait'  
    },  
  
    // styles for the overlay  
    overlayCSS:  {  
        backgroundColor: '#000',  
        opacity:         0.6  
    },  
  
    // styles applied when using $.growlUI  
    growlCSS: {  
        width:    '350px',  
        top:      '10px',  
        left:     '',  
        right:    '10px',  
        border:   'none',  
        padding:  '5px',  
        opacity:   0.6,  
        cursor:    null,  
        color:    '#fff',  
        backgroundColor: '#000',  
        '-webkit-border-radius': '10px',  
        '-moz-border-radius':    '10px'  
    },  
      
    // IE issues: 'about:blank' fails on HTTPS and javascript:false is s-l-o-w  
    // (hat tip to Jorge H. N. de Vasconcelos)  
    iframeSrc: /^https/i.test(window.location.href || '') ? 'javascript:false' : 'about:blank',  
  
    // force usage of iframe in non-IE browsers (handy for blocking applets)  
    forceIframe: false,  
  
    // z-index for the blocking overlay  
    baseZ: 1000,  
  
    // set these to true to have the message automatically centered  
    centerX: true, // <-- only effects element blocking (page block controlled via css above)  
    centerY: true,  
  
    // allow body element to be stetched in ie6; this makes blocking look better  
    // on "short" pages.  disable if you wish to prevent changes to the body height  
    allowBodyStretch: true,  
  
    // enable if you want key and mouse events to be disabled for content that is blocked  
    bindEvents: true,  
  
    // be default blockUI will supress tab navigation from leaving blocking content  
    // (if bindEvents is true)  
    constrainTabKey: true,  
  
    // fadeIn time in millis; set to 0 to disable fadeIn on block  
    fadeIn:  200,  
  
    // fadeOut time in millis; set to 0 to disable fadeOut on unblock  
    fadeOut:  400,  
  
    // time in millis to wait before auto-unblocking; set to 0 to disable auto-unblock  
    timeout: 0,  
  
    // disable if you don't want to show the overlay  
    showOverlay: true,  
  
    // if true, focus will be placed in the first available input field when  
    // page blocking  
    focusInput: true,  
  
    // suppresses the use of overlay styles on FF/Linux (due to performance issues with opacity)
  
    applyPlatformOpacityRules: true,  
  
    // callback method invoked when unblocking has completed; the callback is  
    // passed the element that has been unblocked (which is the window object for page  
    // blocks) and the options that were passed to the unblock call:  
    //     onUnblock(element, options)  
    onUnblock: null,  
  
    // don't ask; if you really must know: http://groups.google.com/group/jquery-
en/browse_thread/thread/36640a8730503595/2f6a79a77a78e493#2f6a79a77a78e493  
    quirksmodeOffsetHack: 4  
}; 
Changing the blockUI options is simple and can be done in one of two ways: 
1.	Globally, by directly overriding the values in the $.blockUI.defaults object
2.	Locally, by passing an options object to the blockUI (or block) function. 
Global Overrides
You can change the default options by simply declaring different values for them. For example: 
// change message border  
$.blockUI.defaults.css.border = '5px solid red';  
  
// make fadeOut effect shorter  
$.blockUI.defaults.fadeOut = 200; 
Local Overrides
Local overrides are achieved by passing an object to the blockUI, unblockUI, block or unblock functions. The exact same options are 
available to the local options object as are available in the global object. For example: 
// change message border  
$.blockUI({ css: { border = '5px solid red'} });  
  
...  
  
// make fadeOut effect shorter  
$.unblockUI({ fadeOut: 200 });  
  
...  
  
// use a different message  
$.blockUI({ message: 'Hold on!' });  
  
...  
  
// use a different message  
$('#myDiv').block({ message: 'Processing...' }); 

