[feat] add loading screen and bar

app/nprogress.css

@@ -0,0 +1,84 @@
+/* Make clicks pass-through */
+#nprogress {
+  pointer-events: none;
+}
+
+#nprogress .bar {
+  background: rgb(42, 42, 42);
+
+  position: fixed;
+  z-index: 1031;
+  top: 0;
+  left: 0;
+
+  width: 100%;
+  height: 5px;
+}
+
+/* Fancy blur effect */
+#nprogress .peg {
+  display: block;
+  position: absolute;
+  right: 0px;
+  width: 100px;
+  height: 100%;
+  box-shadow: 0 0 10px rgb(147, 147, 147), 0 0 5px rgb(147, 147, 147);
+  opacity: 1.0;
+
+  -webkit-transform: rotate(3deg) translate(0px, -4px);
+  -ms-transform: rotate(3deg) translate(0px, -4px);
+  transform: rotate(3deg) translate(0px, -4px);
+}
+
+/* Remove these to get rid of the spinner */
+#nprogress .spinner {
+  display: block;
+  position: fixed;
+  z-index: 1031;
+  top: 15px;
+  right: 15px;
+}
+
+#nprogress .spinner-icon {
+  width: 18px;
+  height: 18px;
+  box-sizing: border-box;
+
+  border: solid 2px transparent;
+  border-top-color: rgb(73, 73, 73);
+  border-left-color: rgb(67, 67, 67);
+  border-radius: 50%;
+
+  -webkit-animation: nprogress-spinner 400ms linear infinite;
+  animation: nprogress-spinner 400ms linear infinite;
+}
+
+.nprogress-custom-parent {
+  overflow: hidden;
+  position: fixed;
+}
+
+.nprogress-custom-parent #nprogress .spinner,
+.nprogress-custom-parent #nprogress .bar {
+  position: absolute;
+}
+
+@-webkit-keyframes nprogress-spinner {
+  0% {
+    -webkit-transform: rotate(0deg);
+  }
+
+  100% {
+    -webkit-transform: rotate(360deg);
+  }
+}
+
+@keyframes nprogress-spinner {
+  0% {
+    transform: rotate(0deg);
+  }
+
+  100% {
+    transform: rotate(360deg);
+  }
+}