<?php
     $hello = "Hi!";
     $a = 'hello';
     echo $$a; 
// output "Hi!"
?>

<?php

 // Multidimensional array
 $regions = [
     "Kakheti"=> [
          "city_1"=>"Telavi",
          "city_2"=>"Gurjaani",
          "city_3"=>"Kvareli",
          "City_4"=>"Sighnaghi"
      ],
      "ShidaKartli"=> [
          "City_1"=>"Kaspi",
          "City_2"=>"Gori",
          "City_3"=>"Kareli",
          "City_4"=>"Khashuri"
      ],
      
      "Imereti"=> [
          "city_1"=>"Kutaisi",
          "city_2"=>"Zestafoni",
          "city_3"=>"Terjola",
          "City_4"=>"Chiatura"
      ]
  ];
  echo 'Kakheti is the region of Georgia' . '.' .  ' Its largest city is ' . $regions['Kakheti']['city_1'] . "\n";
  echo 'My homeland is ' . $regions['ShidaKartli']['City_1'] . '.' . 'I like also ' . $regions['ShidaKartli']['City_2'] .  "\n";
  echo '2 years ago'.  ',' . ' I visited to Imereti Firstly I  went to ' . $regions['Imereti']['city_1'] . "\n"; 
  echo 'after I went to '. $regions['Imereti']['city_3'] . ' and ' . $regions['Imereti']['city_2'] . "\n";
  
  ?> 

<?php
$n1 =15;
$n2 = 9;
$mod = $n1%$n2;
echo $mod;
//output 6
?>

$x++; // equivalent to $x = $x+1;
$x--; // equivalent to $x = $x-1; 
$x++; // post-increment 
$x--; // post-decrement 
++$x; // pre-increment 
--$x; // pre-decrement

$a  = 2; $b = $a++; // $a=3,  $b=2
$a  = 2; $b = ++$a; // $a=3,  $b=3

<?php

   # String Functions

     // Function strlen() returns the length of the string, example:
      echo strlen ("Nice to meet you!") . "\n"; /* output - 17 */

     // Function strrev() returns the Reverse of the string, example:
      echo strrev ("Nice to meet you!") . "\n"; /* output - !uoy teem ot eciN */

     // Function strpos() tries to find the second parameter and returns its index. example:
      echo strpos ("Nice to meet you", "you") . "\n"; /* output - 13 */;

     // Function str_replace() replaces the word "Hello" with "Hi" , example:
      echo ("Hello", "Hi", "Hello there") . "\n"; // outputs - Hi there;

     // Function substr() returns the substring between given indexes, example:
      echo substr("Nice to meet you", "5") . "\n"; // outputs - to meet you;
      echo substr("Nice to meet you", 5, 3) . "\n"; // outputs - to meet you;

     // Function trim() removes whitespaces from sides of the string, example:
      echo trim("  Nice to meet you  ") . "\n"; // outputs - Nice to meet you;

     // Function strtoupper() converts the string to upper case, example:
      echo strtoupper("Nice to meet you") . "\n"; //outputs - NICE TO MEET YOU;
    
    // Function strtolower() converts the string to lower case, example:
      echo strtolower("NICE To Meet You") ; //outputs - nice to meet you;
    
    // Function explode() breaks the string by its delimiter, example:
      print_r (explode(" ", "It's the first day of the course!"));
    
    // Function implode() joins the array element based on the delimiter and returns the string, example:
      echo implode(" ", ['Nice', 'to', 'meet', 'you']); //outputs - Nice to meet you;

    // The PHP str_word_count() function counts the number of words in a string, example:
      echo str_word_count("Nice to meet you!"); // outputs - 4
?>

$primaryColor: #ec7705;
a {
    color: $primaryColor;
}

a {
    color: #ec7705;
}

.site-header nav {
    ul {
        padding: 0;
        margin: 0;
    }
    li {
        list-style: none;
        float: left;
    }
}

.site-header nav ul {
    padding: 0;
    margin: 0;
}
.site-header nav li {
    list-style: none;
    float: left;
}

css-minify

globally

npm install css-minify -g

css-dist

css-minify -f css/d1.css

headers

expires

sudo a2enmod headers 
sudo a2enmod expires

service apache2 restart

.htaccess

# for enabling browser caching
<filesMatch ".(css|jpg|jpeg|png|gif|js|ico)$">
Header set Cache-Control "max-age=2592000, public"
</filesMatch>

.btn-a {
    display: inline-block;
    padding: 10px;
}
.btn-b {
    @extend .btn-a;
    background-color: black;
}

.btn-a, .btn-b {
    display: inline-block;
    padding: 10px;
}
.btn-b {
    background-color: black;
}