Added watermark and springs

src/browser/themes/shared/zen-browser-shared.css

@@ -524,3 +524,31 @@ panelmultiview {
   right: 1.5%;
 }
 
+/* Watermark */
+
+#zen-watermark {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background: var(--zen-main-browser-background);
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  z-index: 9999;
+}
+
+#zen-watermark image {
+  opacity: .2;
+  filter: grayscale(100%);
+  width: 200px;
+  height: 200px;
+}
+
+#zen-watermark[hidden="true"] {
+  transition: .2s;
+  transition-delay: 2s;
+  opacity: 0;
+  pointer-events: none;
+}