Update style.css

style.css

@@ -1,28 +1,68 @@
-body {
-	padding: 2rem;
-	font-family: -apple-system, BlinkMacSystemFont, "Arial", sans-serif;
-}
-
-h1 {
-	font-size: 16px;
-	margin-top: 0;
-}
-
-p {
-	color: rgb(107, 114, 128);
-	font-size: 15px;
-	margin-bottom: 10px;
-	margin-top: 5px;
-}
-
-.card {
-	max-width: 620px;
-	margin: 0 auto;
-	padding: 16px;
-	border: 1px solid lightgray;
-	border-radius: 16px;
-}
-
-.card p:last-child {
-	margin-bottom: 0;
+:root{
+  --primary-color-start:#4F46E5;
+  --primary-color-end:#8B5CF6;
+  --background-color:#f8f9fc;
+  --container-bg:#ffffff;
+  --text-color:#1f2937;
+  --label-color:#374151;
+  --border-color:#d1d5db;
+  --shadow-color:rgba(0,0,0,0.08);
+}
+*{box-sizing:border-box}
+body{
+  margin:0; min-height:100svh; display:grid; place-items:center;
+  background:var(--background-color);
+  font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;
+  color:var(--text-color);
+}
+.app{
+  width:100%; max-width:450px; background:var(--container-bg); padding:30px;
+  border-radius:15px; box-shadow:0 4px 15px var(--shadow-color);
+  border-top:5px solid transparent;
+  background-image: linear-gradient(var(--container-bg), var(--container-bg)), linear-gradient(90deg,var(--primary-color-start),var(--primary-color-end));
+  background-origin: border-box; background-clip: padding-box, border-box;
+}
+h1{
+  margin:0 0 16px; font-size:2em; line-height:1.1; text-align:center;
+  background:linear-gradient(90deg,var(--primary-color-start),var(--primary-color-end));
+  -webkit-background-clip:text; background-clip:text; color:transparent;
+}
+.label{ color:var(--label-color); font-size:.95rem; margin-bottom:6px; display:block }
+.input, .textarea, select{
+  width:100%; padding:14px 12px; border:1px solid var(--border-color); border-radius:8px; background:#fff;
+}
+.top-input{ margin-bottom:12px }
+.options{ display:grid; gap:14px; margin-top:8px }
+.group{ display:grid; gap:8px }
+.group.cols-3{ grid-template-columns:1fr 1fr 1fr; align-items:end; gap:8px 12px }
+.group.cols-3 .label{margin:0}
+.toggles{ display:flex; flex-wrap:wrap; gap:8px }
+.toggle{
+  padding:12px 14px; border-radius:999px; border:1px solid var(--border-color); background:#fff; cursor:pointer;
+  transition:transform .02s ease, box-shadow .15s ease, opacity .15s ease;
+}
+.toggle:hover{ box-shadow:0 0 0 2px rgba(79,70,229,.15) }
+.toggle[aria-pressed="true"], .toggle.selected{
+  color:#fff; border-color:transparent;
+  background:linear-gradient(90deg,var(--primary-color-start),var(--primary-color-end));
+}
+.notes{ display:grid; gap:10px; margin-top:12px }
+.textarea{ resize:vertical }
+.btn{
+  padding:16px; border-radius:10px; border:none; font-weight:700; cursor:pointer;
+  background:linear-gradient(90deg,var(--primary-color-start),var(--primary-color-end)); color:#fff;
+  transition:transform .02s ease, box-shadow .15s ease; width:100%;
+}
+.btn:hover{ box-shadow:0 0 0 4px rgba(79,70,229,.15) }
+.btn:active{ transform:scale(.98) }
+.start{ margin-top:4px }
+.response{ margin-top:16px; display:grid; gap:10px }
+.out{
+  min-height:140px; white-space:pre-wrap; background:#fff; border:1px solid var(--border-color);
+  border-radius:8px; padding:14px; font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace;
+}
+.hint{ font-size:.9rem; color:#4b5563; min-height:1.2em }
+.hidden{ display:none }
+@media (max-width:480px){
+  .btn{ padding:14px }
 }