Add docs navigation and tighten API request security

app/docs/page.module.css

@@ -0,0 +1,66 @@
+.layout {
+  display: grid;
+  grid-template-columns: 240px minmax(0, 1fr);
+  gap: 48px;
+}
+.menu {
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+}
+.menu a {
+  line-height: 1.5;
+}
+.menu a[aria-current="page"] {
+  color: var(--green);
+  font-weight: 700;
+}
+.article {
+  min-width: 0;
+  max-width: 780px;
+}
+.article h1 {
+  font-size: clamp(30px, 4vw, 48px);
+}
+.article a {
+  color: var(--green);
+  text-decoration: underline;
+  text-underline-offset: 3px;
+}
+.article li {
+  margin: 8px 0;
+  line-height: 1.7;
+}
+.article ol { list-style: decimal; padding-left: 24px; }
+.article ul { list-style: disc; padding-left: 24px; }
+.article blockquote {
+  margin: 24px 0;
+  padding: 12px 20px;
+  border-left: 3px solid var(--green);
+}
+.article figure {
+  margin: 24px 0;
+}
+.article img {
+  max-width: 100%;
+  height: auto;
+  border-radius: 12px;
+}
+.paging {
+  display: flex;
+  flex-wrap: wrap;
+  justify-content: space-between;
+  gap: 24px;
+  margin-top: 48px;
+}
+@media (max-width: 800px) {
+  .layout {
+    grid-template-columns: minmax(0, 1fr);
+    gap: 32px;
+  }
+  .menu {
+    flex-direction: row;
+    flex-wrap: wrap;
+    gap: 10px 20px;
+  }
+}