不需要的刷新页面bootstrap / font-face

hi there ia have a html code like this

<html lang="en">
    <head>
    <link href="css/style.css" rel="stylesheet">

</head>


<body>
<?php 
$_SESSION["iphrase"] = $_SESSION["iphrase"] +1;
echo $_SESSION["iphrase"];?>
</body>

</html>

and in css:

@font-face {
    font-family: 'Droid-Naskh';
    font-style: normal;
    font-weight: normal;
    src: url('../fonts/DroidNaskh-Regular.woff2') format('woff2'), url('../fonts/DroidNaskh-Regular.woff') format('woff');
}

body {
  font-family: 'Droid-Naskh';}

for each refresh page I expect this result: 1,2,3,4,5,6...

But it print: 1,3,5,7

the problem is for this code:

 body {
      font-family: 'Droid-Naskh';}

why and how fixed it?

Try something like this

$_SESSION["iphrase"] = (isset($_SESSION["iphrase"])) ? $_SESSION["iphrase"] + 1 : $_SESSION["iphrase"];

echo $_SESSION["iphrase"];

I'm considering you've written session_start(); at the top, somewhere in the code before incrementing session value.