Change background colour in navbar if url contains right string - php

Question

I would like to make navbar, in which background colour of one element would change if user would be on that subpage.
Code for checking if url contains chosen string:
<?php
$url = $_SERVER['REQUEST_URI'];
//echo ($url);
if (strpos($url, 'index.php') == true) {
//echo 'Current page contains index.php';
$atm = "#2275A8";
} else {
$atm = "#00427A";
}
?>
This is part from same file saved as .php file
<?php
header("Content-type: text/css");
?>
.ico1 {
background: <?php echo $atm; ?>;
}
If i put my "ckecking part" od code on index, it is working nicely; returning true or false, but for some reason it's not passing parameter into style file.
So now i put "checking part" into style file but, no mater on which subpage i am, its returning same result (always true even if 'index' is not part of url).
Any idea on how to deal with this? :)

Answer 1

Define classes with style you want in style.css file and change the class of element you want to change style of dynamically in php file like in the example below.
style.css
.ico1 {
background: color1;
}
.ico2 {
background: color2;
}
index.php (or the file containing navbar you want to change)
<?php
$url = $_SERVER['REQUEST_URI'];
if (strpos($url, 'index.php') == true) {
//echo 'Current page contains index.php';
$atm = "ico1";
} else {
$atm = "ico2";
}
?>
...
<div class="<?php echo $atm;?>"> // navbar

Answer 2

Why don't you have the two css classes and make a conditional in the element you want the class be applied:
CSS
.ico1-0 {
background: #2275A8;
}
.ico1-1 {
background: #00427A;
}
PHP
[...]
<div class="<?php echo (strpos($url, 'index.php') === true) ? 'ico1-0' : 'ico1-1'; ?>"></div>
[...]

Answer 3

strpos will never return true. Either it will return false or it return integer. So try like below.
if (strpos($url, 'index.php') !== false)