diff --git a/Activity_PHP/date_of_birth/index.php b/Activity_PHP/date_of_birth/index.php
new file mode 100644
index 0000000..b836a31
--- /dev/null
+++ b/Activity_PHP/date_of_birth/index.php
@@ -0,0 +1,79 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Which Day of the Week Were You Born On?</title>
+    <link rel="stylesheet" href="style.css">
+</head>
+<body>
+    <h1>Which day of the week were you born on?</h1>
+    
+    <form method="post">
+        <div>
+            <label for="firstName">Your first name:</label>
+            <input type="text" name="firstName" required>
+        </div>
+        
+        <h2>Your date of birth:</h2>
+
+        <div class="dob">
+            <label for="day">Day of the month:</label>
+            <input type="number" name="day" required>
+
+            <label for="month">Month:</label>
+            <input type="number" name="month" required>
+
+            <label for="year">Year:</label>
+            <input type="number" name="year" required>
+        </div>
+
+        <button type="submit" name="submit">Validate</button>
+    </form>
+
+    <div>
+        <?php 
+        if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST['submit'])) {
+            $day = $_POST['day'];
+            $month = $_POST['month'];
+            $year = $_POST['year'];
+            $firstName = $_POST['firstName'];
+
+            if ($month < 3) {
+                $dayOfWeek = ( (int)((23 * $month) / 9) + $day + 4 + $year + ((int)($year - 1) / 4) - (int)(($year - 1) / 100) + (int)(($year - 1) / 400) ) % 7;
+            } else {
+                $dayOfWeek = ( (int)((23 * $month) / 9) + $day + 2 + $year + (int)($year / 4) - (int)($year / 100) + (int)($year / 400) ) % 7;
+            }
+
+            switch ($dayOfWeek) {
+                case 0:
+                    $dayOfWeek = "Sunday";
+                    break;
+                case 1:
+                    $dayOfWeek = "Monday";
+                    break;
+                case 2:
+                    $dayOfWeek = "Tuesday";
+                    break;
+                case 3:
+                    $dayOfWeek = "Wednesday";
+                    break;
+                case 4:
+                    $dayOfWeek = "Thursday";
+                    break;
+                case 5:
+                    $dayOfWeek = "Friday";
+                    break;
+                case 6:
+                    $dayOfWeek = "Saturday";
+                    break;
+                default:
+                    $dayOfWeek = "Invalid day";
+            }
+            
+            echo "$firstName, you were born on a $dayOfWeek.";
+        }
+        ?>
+    </div>
+</body>
+</html>
diff --git a/Activity_PHP/date_of_birth/ne_e_quel_jour.css b/Activity_PHP/date_of_birth/ne_e_quel_jour.css
deleted file mode 100644
index 8a8c0e8..0000000
--- a/Activity_PHP/date_of_birth/ne_e_quel_jour.css
+++ /dev/null
@@ -1,12 +0,0 @@
-body {
-    background-color: floralwhite;
-}
-
-h1,
-h2 {
-    color: blue;
-}
-
-.ne {
-    display: flex;
-}
\ No newline at end of file
diff --git a/Activity_PHP/date_of_birth/ne_e_quel_jour.php b/Activity_PHP/date_of_birth/ne_e_quel_jour.php
deleted file mode 100644
index 0e2b3cd..0000000
--- a/Activity_PHP/date_of_birth/ne_e_quel_jour.php
+++ /dev/null
@@ -1,31 +0,0 @@
-<html>
-<head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>Calculatrice</title>
-    <link rel="stylesheet" href="ne_e_quel_jour.css">
-</head>
-<body>
-    <h1>Quel jour de la semaine êtes-vous né(e) ?</h1>
-    
-    <form method="post" action="ne_e_quel_jour2.php">
-        <div>
-            <h2>Votre prénom : </h2>
-            <input type="text" name="prenom" require>
-        </div>
-        
-        <h3>Votre date de naissance SVP ?:</h3>
-
-        <div class="ne">
-            <h2>Jour du mois : </h2>
-            <input type="text" name="jours" require>
-            <h2>mois : </h2>
-            <input type="text" name="mois" require>
-            <h2>année : </h2>
-            <input type="text" name="annees" require>
-        </div>
-
-        <input type="submit">
-    </form>
-</body>
-</html>
\ No newline at end of file
diff --git a/Activity_PHP/date_of_birth/ne_e_quel_jour2.php b/Activity_PHP/date_of_birth/ne_e_quel_jour2.php
deleted file mode 100644
index d1651d6..0000000
--- a/Activity_PHP/date_of_birth/ne_e_quel_jour2.php
+++ /dev/null
@@ -1,46 +0,0 @@
-<html>
-<head>
-    <meta charset="UTF-8">
-    <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <title>Calculatrice</title>
-    <link rel="stylesheet" href="ne_e_quel_jour.css">
-</head>
-<body>
-    <h1>Quel jour de la semaine êtes-vous né(e) ?</h1>
-    
-    <h3>
-    <?php 
-    $nbr = $_POST['jours'];
-    $mois = $_POST['mois'];
-    $annees = $_POST['annees'];
-    if ($mois<3) {
-        $jour = ( (int)((23*$mois)/9)+$nbr+4+$annees+((int)($annees-1)/4)-(int)(($annees-1)/100)+(int)(($annees-1)/400) )%7;
-    } else {
-        $jour = ( (int)((23*$mois)/9)+$nbr+2+$annees+(int)($annees/4)-(int)($annees/100)+(int)($annees/400) )%7;
-    }
-    $nom = $_POST['prenom'];
-
-    if ($jour == 0) {
-        $jour = "dimanche";
-    } elseif($jour == 1) {
-        $jour = "lundi";
-    } elseif($jour == 2) {
-        $jour = "mardi";
-    } elseif($jour == 3) {
-        $jour = "mercredi";
-    } elseif($jour == 4) {
-        $jour = "jeudi";
-    } elseif($jour == 5) {
-        $jour = "vendredi";
-    } elseif($jour == 6) {
-        $jour = "samedi";
-    }
-    
-    
-
-    print("$nom, vous êtes né(e) un $jour.");
-
-    ?>
-    </h3>
-</body>
-</html>
\ No newline at end of file
diff --git a/Activity_PHP/date_of_birth/style.css b/Activity_PHP/date_of_birth/style.css
new file mode 100644
index 0000000..5a265e4
--- /dev/null
+++ b/Activity_PHP/date_of_birth/style.css
@@ -0,0 +1,32 @@
+body {
+   font-family: Arial, sans-serif;
+   margin: 0;
+   padding: 0;
+   text-align: center;
+}
+
+h1 {
+   margin-top: 20px;
+}
+
+form {
+   margin-top: 20px;
+}
+
+input[type="text"],
+input[type="number"],
+button {
+   margin: 5px;
+   padding: 5px;
+   border-radius: 5px;
+   border: 1px solid #ccc;
+}
+
+button {
+   cursor: pointer;
+}
+
+div {
+   margin-top: 20px;
+   font-weight: bold;
+}
diff --git a/Activity_PHP/the_sphere/lasphere.php b/Activity_PHP/the_sphere/index.php
similarity index 100%
rename from Activity_PHP/the_sphere/lasphere.php
rename to Activity_PHP/the_sphere/index.php
