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What are the implications of using “!important” in CSS? [duplicate]

...portant: Specificity is one of the main forces at work when the browser decides how CSS affects the page. The more specific a selector is, the more importance is added to it. This usually coincides with how often the selected element occurs. For example: button { color: black; } button.highl...
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How to communicate between iframe and the parent site?

...actice, never use the '*' for your target. In fact, MDN says - "Always provide a specific targetOrigin, not *, if you know where the other window's document should be located. Failing to provide a specific target discloses the data you send to any interested malicious site." – ...
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What does mvn install in maven exactly do

... As you might be aware of, Maven is a build automation tool provided by Apache which does more than dependency management. We can make it as a peer of Ant and Makefile which downloads all of the dependencies required. On a mvn install, it frames a dependency tree based on the project con...
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What does $$ (dollar dollar or double dollar) mean in PHP?

... such as $$variable is called Variable Variable. For example, if you consider this portion of code : $real_variable = 'test'; $name = 'real_variable'; echo $$name; You will get the following output : test Here : $real_variable contains test $name contains the name of your variable : 'real...
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Difference between Key, Primary Key, Unique Key and Index in MySQL

... A primary key is a column, or a combination of columns, that can uniquely identify a row. It is a special case of unique key. A table can have at most one primary key, but more than one unique key. When you specify a unique key on a column, no two distinct rows in a table can have the same value. ...
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Removing list of vms in vagrant cache

... You should use the following command to remove invalid entries from the global index: vagrant global-status --prune share | improve this answer | fol...
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Is there a simple, elegant way to define singletons? [duplicate]

...on in use of your API. I would still just put methods in a module, and consider the module as the singleton. share | improve this answer | follow | ...
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Drop shadow for PNG image in CSS

...25px rgba(0,0,0,0.5)); filter: url(#drop-shadow); -ms-filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#444')"; filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#444')"; } <!-- HTML elements here --> <svg height="0" ...
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Animated loading image in picasso

...ml <?xml version="1.0" encoding="utf-8"?> <layer-list xmlns:android="http://schemas.android.com/apk/res/android"> <item android:gravity="center"> <animated-rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/progress_image"...
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Equal sized table cells to fill the entire width of the containing table

...HTML/CSS (with relative sizing) to make a row of cells stretch the entire width of the table within which it is contained? ...