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Border overlap means that the adjacent borders of two or more boxes (which may be adjacent or nested) (without any non-empty content, padding, or borders in between) overlap to form a single border. The vertically adjacent boundaries of two or more block-level boxes will overlap. The resulting border width is the largest of adjacent border widths. If a negative boundary occurs, the negative boundary with the largest absolute value is subtracted from the largest positive boundary. If there are no positive boundaries, the negative boundary with the largest absolute value is subtracted from zero. Note: Adjacent boxes may not be generated by elements with parent-child or sibling relationships. But there are exceptions to the overlap of boundaries: 1. The horizontal margins will never overlap. 2. In the specification document, the adjacent vertical margins of two or more block-level box models will overlap. The final margin value is calculated as follows: a. If all are positive values, take the largest one; b. If they are not all positive values, take the absolute value, and then subtract the maximum value from the positive value; c. If there is no positive value, take the absolute value, and then subtract the maximum value from 0. Note: Adjacent box models may be dynamically generated by DOM elements and are not
1.CSS margin overlap and prevention methods
# Introduction: Boundary overlap refers to the adjacent boundaries of two or more boxes (which may be adjacent or nested) (without any non-empty spaces in between) content, padding, borders) overlap to form a single border. The vertically adjacent boundaries of two or more block-level boxes will overlap. The resulting border width is the largest of adjacent border widths. If a negative boundary occurs, the negative boundary with the largest absolute value is subtracted from the largest positive boundary. If there are no positive boundaries, the negative boundary with the largest absolute value is subtracted from zero. Note: Adjacent boxes may not be generated by elements with parent-child or sibling relationships.
2.php sql injection and anti-injection classic case analysis_PHP tutorial
Introduction: php sql injection and anti-injection Anti-injection classic case analysis. SQL injection and injection prevention are actually a combination of attack and defense. Today we are going to tell you the most basic injection and prevention methods. The principles are all based on some features of php or mysql that we have not paid attention to
3.Linux solution to prevent PHP from forging local files_PHP tutorial
Introduction: Linux prevents PHP from forging local files. We will only talk about the Linux system as an example, but the prevention method is effective in any system. Let’s take a look at the following operations. You can use the code like this. Copy the code as follows http://www.xx
4.Linux solution to prevent PHP from forging local files
Introduction: Linux prevents PHP from forging local files. We only talk about the Linux system as an example, but the prevention method is effective in any system. Let's first look at the operation. You can use the code like this. Copy the code as follows http://www.xx
5.Linux solution to prevent PHP from forging local files
Introduction: We only talk about the Linux system as an example, but the prevention method can be applied to any system. Effective, let’s take a look at the following operations first. You can use it like this. The code is as follows: http://www.phprm.com/index.php?page=../e...
6.php sql injection and anti-injection classic case analysis
Introduction: SQL injection and anti-injection are actually an attack and defense. Today we are going to tell you the most basic injection and prevention methods. The principles are caused by using some features of PHP or MySQL without us paying attention. A simple SQL injection attack case. If we have a public...
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