feat: add opt-in procedural drive audio

src/styles/world.css

@@ -93,14 +93,33 @@
   font-size: var(--step--1);
 }
 
+.drive-controls__audio-start,
+.drive-controls__audio {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: 0.55rem;
+}
+
+.drive-controls__audio-start span,
+.drive-controls__audio-status {
+  color: var(--text-muted);
+}
+
 .drive-controls button,
-.drive-controls select {
+.drive-controls select,
+.drive-controls input {
   min-block-size: 44px;
   border: 1px solid var(--line-strong);
   background: #101925;
   color: var(--text);
 }
 
+.drive-controls input[type='range'] {
+  inline-size: 7rem;
+  accent-color: var(--cyan);
+}
+
 .drive-controls button {
   padding-inline: 0.8rem;
 }
@@ -120,6 +139,18 @@
 }
 
 @media (max-width: 767px) {
+  html {
+    scroll-padding-block-end: 11rem;
+  }
+
+  #contact {
+    padding-block-end: 11rem;
+  }
+
+  #contact a {
+    scroll-margin-block-end: 11rem;
+  }
+
   .journey-hud {
     inset: 0.5rem 0.5rem auto auto;
     min-inline-size: 0;
@@ -138,6 +169,10 @@
   .drive-controls__status {
     flex-basis: 100%;
   }
+
+  .drive-controls__audio-start span {
+    flex-basis: 100%;
+  }
 }
 
 @media (prefers-reduced-motion: reduce) {