added loading placeholder when searching; added loading placeholder when changing tabs in search tab

src/styles/scss/base/_animations.scss

@@ -1,3 +1,45 @@
+/* Source: https://loading.io/css/ */
+.lds-ring {
+	display: inline-block;
+	position: relative;
+	width: 80px;
+	height: 80px;
+
+	div {
+		box-sizing: border-box;
+		display: block;
+		position: absolute;
+		width: 64px;
+		height: 64px;
+		margin: 8px;
+		border: 8px solid #fff;
+		border-radius: 50%;
+		animation: lds-ring 1.2s cubic-bezier(0.5, 0, 0.5, 1) infinite;
+		border-color: #fff transparent transparent transparent;
+
+		&:nth-child(1) {
+			animation-delay: -0.45s;
+		}
+
+		&:nth-child(2) {
+			animation-delay: -0.3s;
+		}
+
+		&:nth-child(3) {
+			animation-delay: -0.15s;
+		}
+	}
+}
+
+@keyframes lds-ring {
+	0% {
+		transform: rotate(0deg);
+	}
+	100% {
+		transform: rotate(360deg);
+	}
+}
+
 @keyframes spin {
 	from {
 		transform: rotate(0deg);