{"rowid": 335, "title": "Naughty or Nice? CSS Background Images", "contents": "Web Standards based development involves many things \u2013 using semantically sound HTML to provide structure to our documents or web applications, using CSS for presentation and layout, using JavaScript responsibly, and of course, ensuring that all that we do is accessible and interoperable to as many people and user agents as we can.\n\nThis we understand to be good. \n\nAnd it is good. \n\nExcept when we don\u2019t clearly think through the full implications of using those techniques.\n\nWhich often happens when time is short and we need to get things done.\n\nHere are some naughty examples of CSS background images with their nicer, more accessible counterparts.\n\nTransaction related messages\n\nI\u2019m as guilty of this as others (or, perhaps, I\u2019m the only one that has done this, in which case this can serve as my holiday season confessional)  We use lovely little icons to show status messages for a transaction to indicate if the action was successful, or was there a warning or error? For example:\n\n\u201cYour postal/zip code was not in the correct format.\u201d\n\nNotice that we place a nice little icon there, and use background colours and borders to convey a specific message: there was a problem that needs to be fixed. Notice that all of this visual information is now contained in the CSS rules for that div:\n\n<div class=\"error\">\n     <p>Your postal/zip code was not in the correct format.</p>\n </div>\n\n div.error {\n     background: #ffcccc url(../images/error_small.png) no-repeat 5px 4px;\n     color: #900;\n     border-top: 1px solid #c00;\n     border-bottom: 1px solid #c00;\n     padding: 0.25em 0.5em 0.25em 2.5em;\n     font-weight: bold;\n }\n\nUsing this approach also makes it very easy to create a div.success and div.warning CSS rules meaning we have less to change in our HTML.\n\nNice, right?\n\nNo. Naughty. \n\nVisual design communicates\n\nThe CSS is being used to convey very specific information. The choice of icon, the choice of background colour and borders tell us visually that there is something wrong. \n\nWith the icon as a background image \u2013 there is no way to specify any alt text for the icon, and significant meaning is lost. A screen reader user, for example, misses the fact that it is an \u201cerror.\u201d \n\nThe solution? Ask yourself: what is the bare minimum needed to indicate there was an error? Currently in the absence of CSS there will be no icon \u2013 which (I\u2019m hoping you agree) is critical to communicating there was an error.\n\nThe icon should be considered content and not simply presentational.\n\nThe borders and background colour are certainly much less critical \u2013 they belong in the CSS.\n\nLets change the code to place the image directly in the HTML and using appropriate alt text to better communicate the meaning of the icon to all users:\n\n<div class=\"bettererror\">\n     <img src=\"images/error_small.png\" alt=\"Error\" />\n     <p>Your postal/zip code was not in the correct format.</p>\n </div>\n\n div.bettererror {\n     background-color: #ffcccc;\n     color: #900;\n     border-top: 1px solid #c00;\n     border-bottom: 1px solid #c00;\n     padding: 0.25em 0.5em 0.25em 2.5em;\n     font-weight: bold;\n     position: relative;\n     min-height: 1.25em;\n }\n\n div.bettererror img {\n     display: block;\n     position: absolute;\n     left: 0.25em;\n     top: 0.25em;\n     padding: 0;\n     margin: 0;\n }\n\n div.bettererror p {\n     position: absolute;\n     left: 2.5em;\n     padding: 0;\n     margin: 0;\n }\n\nCompare these two examples of transactional messages\n\nStatus of a Record\n\nThis example is pretty straightforward. Consider the following: a real estate listing on a web site. There are three \u201cstates\u201d for a listing: new, normal, and sold. Here\u2019s how they look:\n\nExample of a New Listing\n\nExample of A Sold Listing\n\nIf we (forgive the pun) blindly apply the \u201cuse a CSS background image\u201d technique we clearly run into problems with the new and sold images \u2013 they actually contain content with no way to specify an alternative when placed in the CSS.\n\nIn this case of the \u201cnew\u201d image, we can use the same strategy as we used in the first example (the transaction result). The \u201cnew\u201d image should be considered content and is placed in the HTML as part of the <h2>...</h2> that identifies the listing.\n\nHowever when considering the \u201csold\u201d listing, there are less changes to be made to keep the same look by leaving the \u201cSOLD\u201d image as a background image and providing the equivalent information elsewhere in the listing \u2013 namely, right in the heading.\n\nFor those that can\u2019t see the background image, the status is communicated clearly and right away. A screen reader user that is navigating by heading or viewing a listing will know right away that a particular property is sold.\n\nOf note here is that in both cases (new and sold) placing the status near the beginning of the record helps with a zoom layout as well.\n\nBetter Example of A Sold Listing\n\nSummary\n\nRemember: in the holiday season, its what you give that counts!! Using CSS background images is easy and saves time for you but think of the children. And everyone else for that matter\u2026 \n\nCSS background images should only be used for presentational images, not for those that contain content (unless that content is already represented and readily available elsewhere).", "year": "2005", "author": "Derek Featherstone", "author_slug": "derekfeatherstone", "published": "2005-12-20T00:00:00+00:00", "url": "https://24ways.org/2005/naughty-or-nice-css-background-images/", "topic": "code"}