add history page and submission tracking functionality

style/main.scss

@@ -2,6 +2,7 @@ body {
 	min-height: 100vh;
 	margin: 0;
 	display: grid;
+	grid-template-columns: minmax(0, 1fr);
 	place-items: center;
 	padding: 24px;
 	box-sizing: border-box;
@@ -13,10 +14,15 @@ body {
 }
 
 main {
-	width: min(100%, 480px);
+	width: 100%;
+	max-width: 1200px;
+	box-sizing: border-box;
 }
 
 .status-card {
+	width: min(100%, 480px);
+	box-sizing: border-box;
+	margin-inline: auto;
 	padding: clamp(28px, 7vw, 48px);
 	border: 1px solid rgba(148, 163, 184, 0.2);
 	border-radius: 24px;
@@ -55,6 +61,17 @@ h1 {
 	gap: 12px;
 }
 
+.history-actions {
+	display: flex;
+	align-items: center;
+	justify-content: space-between;
+	gap: 16px;
+}
+
+.history-actions .status-button {
+	flex: 1;
+}
+
 .key-label {
 	color: #d3dceb;
 	font-size: 0.9rem;
@@ -111,6 +128,14 @@ h1 {
 	background: #d05242;
 }
 
+.clear-history-button {
+	background: #8f3030;
+}
+
+.clear-history-button:hover:not(:disabled) {
+	background: #ad3939;
+}
+
 .status-button:hover:not(:disabled) {
 	transform: translateY(-1px);
 }
@@ -162,18 +187,65 @@ h1 {
 
 .home-link {
 	display: inline-block;
-	margin-top: 24px;
 	color: #8bbaff;
 	font-size: 0.9rem;
 	font-weight: 600;
 	text-decoration: none;
 }
 
+.page-nav {
+	display: flex;
+	align-items: center;
+	justify-content: space-between;
+	gap: 24px;
+	margin-top: 24px;
+}
+
 .home-link:hover {
 	color: #b3d2ff;
 	text-decoration: underline;
 }
 
+.history-card {
+	width: 100%;
+	overflow: hidden;
+}
+
+.history-table-wrap {
+	margin-top: 28px;
+	overflow-x: auto;
+}
+
+.history-table {
+	width: 100%;
+	border-collapse: collapse;
+	text-align: left;
+	white-space: nowrap;
+}
+
+.history-table th,
+.history-table td {
+	padding: 12px 14px;
+	border-bottom: 1px solid rgba(148, 163, 184, 0.16);
+}
+
+.history-table th {
+	color: #a9b6c9;
+	font-size: 0.78rem;
+	font-weight: 700;
+	letter-spacing: 0.06em;
+	text-transform: uppercase;
+}
+
+.history-table td {
+	color: #e6edf7;
+	font-size: 0.9rem;
+}
+
+.history-table tbody tr:last-child td {
+	border-bottom: 0;
+}
+
 @media (prefers-reduced-motion: reduce) {
 	* {
 		transition-duration: 0.01ms !important;