Fix multiple declarations overriding order

[elchininet]

This pull request fixes a bug when the same declaration property is declared multiple times in a rule.

Input

.test {
    color: red;
    text-align: left;
    text-align: center;
}

Output Before

.test {
    color: red;
    text-align: center;
}

[dir="ltr"] .test {
    text-align: left;
}

[dir="rtl"] .test {
    text-align: right;
}

In the original CSS file the text-align: center is overriding the text-align: left but in the output, the opposite occurs due to a higher specificity of the [dir="ltr"] and [dir="rtl"] rules.

Output After the Fix

.test {
    color: red;
}

[dir="ltr"] .test {
    text-align: left;
}

[dir="rtl"] .test {
    text-align: right;
}

[dir] .test {
    text-align: center;
}

The bothPrefix property has been used to create a rule and maintain the same input behavior.