diff --git a/src/components/ui/TerminalPath.astro b/src/components/ui/TerminalPath.astro
index ed7e85d..242dc55 100644
--- a/src/components/ui/TerminalPath.astro
+++ b/src/components/ui/TerminalPath.astro
@@ -1,15 +1,31 @@
 ---
+interface Props {
+  command?: "cat" | "ls" | "exit";
+  value?: string;
+}
+
 const pathname = Astro.url.pathname;
 
-const cleanPath = pathname.replace(/^\/|\/$/g, "");
+const cleanPath = pathname.replace(/^\/+|\/+$/g, "");
+const isDirectory = ["projects", "posts", "games"].includes(cleanPath);
 
-const filePath = cleanPath === "" ? "home.hy" : `${cleanPath}.hy`;
+const command = Astro.props.command ?? (isDirectory ? "ls" : "cat");
+const value =
+  Astro.props.value ??
+  (isDirectory
+    ? `${cleanPath}/`
+    : cleanPath === ""
+      ? "home.hy"
+      : `${cleanPath}.hy`);
 ---
 
-<div class="terminal-path shell" aria-label={`Current path: ${filePath}`}>
+<div
+  class="terminal-path shell"
+  aria-label={`Terminal command: ${command} ${value}`}
+>
   <span class="terminal-path__command">&gt;</span>
-  <span class="terminal-path__command"> cat </span>
-  <span class="terminal-path__value">{filePath}</span>
+  <span class="terminal-path__command"> {command} </span>
+  <span class="terminal-path__value">{value}</span>
 </div>
 
 <style>
diff --git a/src/data/ascii/404.txt b/src/data/ascii/404.txt
new file mode 100644
index 0000000..cc0d930
--- /dev/null
+++ b/src/data/ascii/404.txt
@@ -0,0 +1,6 @@
+██╗  ██╗ ██████╗ ██╗  ██╗
+██║  ██║██╔═████╗██║  ██║
+███████║██║██╔██║███████║
+╚════██║████╔╝██║╚════██║
+     ██║╚██████╔╝     ██║
+     ╚═╝ ╚═════╝      ╚═╝
\ No newline at end of file
diff --git a/src/layouts/BaseLayout.astro b/src/layouts/BaseLayout.astro
index 0472ec1..1d2034a 100644
--- a/src/layouts/BaseLayout.astro
+++ b/src/layouts/BaseLayout.astro
@@ -7,12 +7,18 @@ interface Props {
   title?: string;
   description?: string;
   index?: boolean;
+  terminalCommand?: "cat" | "ls" | "exit";
+  terminalValue?: string;
+  searchIndex?: boolean;
 }
 
 const {
   title = "Hyde.dev",
   description = "Personal developer portfolio.",
   index = true,
+  terminalCommand,
+  terminalValue,
+  searchIndex = true,
 } = Astro.props;
 
 const canonical = new URL(Astro.url.pathname, Astro.site);
@@ -36,9 +42,9 @@ const canonical = new URL(Astro.url.pathname, Astro.site);
     <title>{title}</title>
   </head>
 
-  <body>
+  <body data-pagefind-ignore={searchIndex ? undefined : "all"}>
     <Topbar />
-    <TerminalPath />
+    <TerminalPath command={terminalCommand} value={terminalValue} />
     <slot />
   </body>
 </html>
diff --git a/src/pages/404.astro b/src/pages/404.astro
new file mode 100644
index 0000000..fc3506c
--- /dev/null
+++ b/src/pages/404.astro
@@ -0,0 +1,158 @@
+---
+import BaseLayout from "../layouts/BaseLayout.astro";
+import artwork from "../data/ascii/404.txt?raw";
+
+// Keep indentation within the artwork; only remove surrounding blank lines.
+const ascii = artwork.replace(/\r\n/g, "\n").replace(/^\n+|\n+$/g, "");
+const columns = Math.max(1, ...ascii.split("\n").map((line) => line.length));
+const links = [
+  { href: "/", label: "Go Home" },
+  { href: "/projects", label: "View Projects" },
+  { href: "/posts", label: "Read Posts" },
+];
+---
+
+<BaseLayout
+  title="404 — Page not found | Hyde.dev"
+  description="No such file or directory. Find your way back to Hyde.dev."
+  index={false}
+  searchIndex={false}
+  terminalCommand="exit"
+  terminalValue="1"
+>
+  <main class="shell not-found" aria-labelledby="not-found-title">
+    <div class="not-found__art" aria-hidden="true">
+      <pre style={`--ascii-columns: ${columns}`}>{ascii}</pre>
+    </div>
+
+    <div class="not-found__message">
+      <h1 id="not-found-title">
+        <span class="sr-only">404: </span>Page not found
+      </h1>
+      <p>No such file or directory.</p>
+    </div>
+
+    <nav class="not-found__links" aria-label="Find your way back">
+      {links.map(({ href, label }) => (
+        <a href={href}>
+          <span class="not-found__bracket" aria-hidden="true">
+            [
+          </span>
+          <span class="not-found__link-label">{label}</span>
+          <span class="not-found__arrow" aria-hidden="true">
+            &gt;
+          </span>
+          <span class="not-found__bracket" aria-hidden="true">
+            ]
+          </span>
+        </a>
+      ))}
+    </nav>
+  </main>
+</BaseLayout>
+
+<style>
+  .not-found {
+    padding-block: clamp(2rem, 6vw, 5rem) var(--space-12);
+    text-align: center;
+  }
+
+  .not-found__art {
+    container-type: inline-size;
+    margin-inline: auto;
+    max-width: 68rem;
+    color: var(--color-text);
+    mask-image: linear-gradient(
+      to right,
+      transparent,
+      black 12%,
+      black 88%,
+      transparent
+    );
+  }
+
+  .not-found__art pre {
+    margin: 0;
+    font-family: var(--font-mono);
+    font-size: min(14px, calc(100cqi / var(--ascii-columns) / 0.65));
+    line-height: 1.35;
+    letter-spacing: 0;
+    white-space: pre;
+  }
+
+  .not-found__message {
+    margin-top: clamp(1rem, 2vw, 4rem);
+  }
+
+  h1 {
+    margin: 0;
+    font-size: clamp(1.5rem, 3vw, 2.25rem);
+    font-weight: 400;
+    line-height: 1.4;
+  }
+
+  p {
+    margin: var(--space-1) 0 0;
+    font-size: clamp(0.875rem, 2vw, 1.25rem);
+    line-height: 1.6;
+  }
+
+  .not-found__links {
+    display: flex;
+    flex-wrap: wrap;
+    justify-content: center;
+    gap: var(--space-3) var(--space-8);
+    margin-top: var(--space-8);
+    padding-top: var(--space-3);
+    border-top: var(--border-width) solid var(--color-border);
+  }
+
+  .not-found__links a {
+    display: inline-flex;
+    align-items: center;
+    gap: var(--space-4);
+    min-height: 44px;
+    text-decoration: none;
+  }
+
+  .not-found__link-label {
+    text-decoration: underline;
+    text-underline-offset: 0.3em;
+  }
+
+  .not-found__bracket,
+  .not-found__arrow {
+    color: var(--color-text-muted);
+  }
+
+  .not-found__arrow {
+    transition: transform var(--duration-fast) var(--ease-standard);
+  }
+
+  .not-found__links a:hover .not-found__arrow {
+    color: var(--color-text);
+    transform: translateX(3px);
+  }
+
+  .not-found__links a:focus-visible {
+    outline: 2px solid var(--color-text);
+    outline-offset: 5px;
+  }
+
+  .sr-only {
+    position: absolute;
+    width: 1px;
+    height: 1px;
+    padding: 0;
+    overflow: hidden;
+    clip-path: inset(50%);
+    white-space: nowrap;
+  }
+
+  @media (max-width: 30rem) {
+    .not-found__links {
+      flex-direction: column;
+      align-items: center;
+    }
+  }
+</style>