Fix layout of game screen + language improvemenets

language.js

@@ -5,7 +5,9 @@ const en = {
     "<br>" +
     "Q/E -> Rotate the tile" +
     "<br>" +
-    "Down/S -> Drop the tile faster",
+    "Down/S -> Drop the tile faster" +
+    "<br>" +
+    "Space/Esc -> Pause the game",
     play: "Play!",
     score: "Score: ",
     paused: "Paused",
@@ -21,7 +23,9 @@ const de = {
     "<br>" +
     "Q/E -> Objekt drehen" +
     "<br>" +
-    "Unten/S -> Objekt schneller fallen lassen",
+    "Unten/S -> Objekt schneller fallen lassen" +
+    "<br>" +
+    "Leertaste/Esc -> Pausiere das Spiel",
     play: "Spielen!",
     score: "Punkte: ",
     paused: "Pausiert",

style.css

@@ -77,12 +77,12 @@ body {
 #tetris {
     position: absolute;
     left: 50%;
-    -webkit-transform: translateX(-50%);
-    -moz-transform: translateX(-50%);
-    -ms-transform: translateX(-50%);
-    -o-transform: translateX(-50%);
-    transform: translateX(-50%);
-    margin: 20px 0;
+    top: 50%;
+    -webkit-transform: translate(-50%, -50%);
+    -moz-transform: translate(-50%, -50%);
+    -ms-transform: translate(-50%, -50%);
+    -o-transform: translate(-50%, -50%);
+    transform: translate(-50%, -50%);
     border: solid .2em #fff;
 }