adding portrait mode warning message

timetable/styles.css

@@ -1,6 +1,61 @@
 body {
     background-color: #F6F6F6;
     font-family: Arial, sans-serif;
+    margin: 0;
+    padding: 0;
+}
+
+#landscape-message {
+    position: fixed;
+    top: 0;
+    left: 0;
+    width: 100%;
+    height: 100%;
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    align-items: center;
+    text-align: center;
+}
+
+#logo {
+    max-width: 100%;
+    height: auto;
+    margin-bottom: 20px;
+}
+
+#landscape-message h1 {
+    margin-top: 0;
+}
+
+#landscape-message p {
+    margin: 10px 0;
+}
+
+#timetable {
+    display: none;
+}
+
+@media (orientation: landscape) {
+    #landscape-message {
+        display: none;
+    }
+
+    #timetable {
+        display: block;
+    }
+}
+
+@media (max-height: 600px) {
+    #headline {
+        margin-top: 40px;
+    }
+}
+
+@media (max-height: 400px) {
+    #headline {
+        margin-top: 20px;
+    }
 }
 
 #timetable {
@@ -8,9 +63,11 @@ body {
     margin: 0 auto;
 }
 
-#headline, #subheadline {
+#headline,
+#subheadline {
     text-align: center;
     color: #444;
+    margin-top: 40px;
 }
 
 #slider-container {
@@ -71,7 +128,8 @@ body {
     table-layout: fixed;
 }
 
-.day-table th, .day-table td {
+.day-table th,
+.day-table td {
     border: 1px solid #FFFFFF;
     padding: 10px;
     text-align: center;
@@ -131,3 +189,19 @@ body {
     border-radius: 5px;
     cursor: pointer;
 }
+
+@media (max-width: 600px) {
+    #slider-container {
+        width: 90%;
+    }
+
+    .day-table,
+    .day-table th,
+    .day-table td {
+        font-size: 0.8em;
+    }
+
+    .day-table td {
+        height: auto;
+    }
+}