Move index styles into style.css; restyle 403/404 to match

style.css

@@ -1,48 +1,82 @@
 :root {
-  --bg: #0b1020;
-  --fg: #e6e8ef;
-  --accent: #6ea8fe;
-  --muted: #9aa4bf;
+  --bg: #fafafa;
+  --fg: #1a1a1a;
+  --muted: #666;
+  --line: #ddd;
+  --code-bg: #f0f0f0;
+  --link: #0b5cad;
+  color-scheme: light dark;
+}
+
+@media (prefers-color-scheme: dark) {
+  :root {
+    --bg: #111;
+    --fg: #e6e6e6;
+    --muted: #999;
+    --line: #333;
+    --code-bg: #1c1c1c;
+    --link: #7ab7ff;
+  }
 }
 
 * { box-sizing: border-box; }
 
-html, body {
-  margin: 0;
-  padding: 0;
-  min-height: 100%;
-}
-
 body {
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  min-height: 100vh;
+  margin: 0;
   background: var(--bg);
   color: var(--fg);
-  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
-  line-height: 1.6;
+  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
 }
 
 main {
   max-width: 42rem;
-  padding: 2rem;
-  text-align: center;
+  margin: 0 auto;
+  padding: 3rem 1.25rem;
 }
 
-h1 {
-  font-size: clamp(2rem, 6vw, 3.5rem);
-  margin: 0 0 0.5rem;
-  letter-spacing: -0.02em;
+h1 { font-size: 1.75rem; margin: 0 0 2rem; }
+
+h2 {
+  font-size: .8rem;
+  letter-spacing: .08em;
+  text-transform: uppercase;
+  color: var(--muted);
+  margin: 2.5rem 0 .75rem;
 }
 
-main.error h1 {
-  color: var(--accent);
-  font-size: clamp(4rem, 18vw, 9rem);
+a { color: var(--link); text-decoration: none; }
+a:hover { text-decoration: underline; }
+
+/* Contact list */
+dl {
+  display: grid;
+  grid-template-columns: max-content 1fr;
+  gap: .5rem 1.5rem;
   margin: 0;
 }
+dt { color: var(--muted); }
+dd { margin: 0; overflow-wrap: anywhere; }
 
-p { color: var(--muted); margin: 0.5rem 0; }
+/* Key blocks */
+.key { margin: 0 0 1.25rem; }
+.key p { margin: 0 0 .35rem; color: var(--muted); font-size: .9rem; }
 
-a { color: var(--accent); text-decoration: none; }
-a:hover { text-decoration: underline; }
+pre {
+  margin: 0;
+  padding: .75rem 1rem;
+  background: var(--code-bg);
+  border: 1px solid var(--line);
+  border-radius: 6px;
+  overflow-x: auto;
+  font: .85rem/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
+}
+
+/* Error pages (403/404) */
+main.error h2 { margin-top: 0; }
+main.error h1 { margin-bottom: .75rem; }
+main.error p { color: var(--muted); margin: 0 0 2rem; }
+
+@media (max-width: 30rem) {
+  dl { grid-template-columns: 1fr; gap: 0; }
+  dd { margin-bottom: .75rem; }
+}