Add loading state (initial)

Add rollover actions on train service
Add some additional toc styles

src/lib/components/ui/Loading.svelte

@@ -0,0 +1,59 @@
+<script lang="ts">
+    let {
+        message = "Loading..."
+    } = $props();
+</script>
+
+<div class="loading-state">
+    <div class="track">
+        <div class="shuttle"></div>
+    </div>
+    <p>{message}</p>
+</div>
+
+<style>
+    .loading-state {
+        display: flex;
+        flex-direction: column;
+        justify-content: center;
+        align-items: center;
+        padding: 4rem 2rem;
+        width: 75%;
+        margin: auto;
+    }
+
+    .track {
+        width: 160px;
+        height: 3px;
+        background-color: var(--color-title);
+        border-radius: 4px;
+        position: relative;
+        overflow: hidden;
+    }
+
+    .shuttle {
+        position: absolute;
+        width: 50%;
+        height: 100%;
+        border-radius: 4px;
+        background: linear-gradient(90deg, #1abc9c 0%, #3498db 100%);
+        animation: data-travel 1.6s infinite ease-in-out;
+    }
+
+    p {
+        font-family: 'URW Gothic', sans-serif;
+        letter-spacing: 0.15em;
+        color: var(--color-title);
+        animation: pulse 2s infinite ease-in-out;
+    }
+
+    @keyframes data-travel {
+        0% { left: -50%; }
+        100% { left: 100%; }
+    }
+
+    @keyframes pulse {
+        0%, 100% {opacity: 1;}
+        50% {opacity: 0.4;}
+    }
+</style>