If you want to make sure a particual property must be fixed to a html tag, you nees add the !important property to the declaration.
for e.g. P tag with color red is declared & dont want to change this color property at ant way. Then go for !imprtant
p
{
color : red !important
}
By this way prevent properties from changing value
p
{
color : blue;
}
<p style="color : red">
Both above declaration cannot affect red color of the p tag
