fix: remove code block language label overlap, add diagram zoom/pan/fullscreen

- Remove 'bash' language label that overlapped with code text
- Add zoom (scroll), pan (drag), and fullscreen toggle to Mermaid diagrams
- Fullscreen mode with dark overlay, controls toolbar, and Esc to close
- Zoom percentage indicator and reset button

apps/web/src/components/code-block.tsx

@@ -20,7 +20,6 @@ export function CodeBlock({ children, className, inline }: CodeBlockProps) {
     );
   }
 
-  const language = className?.replace("language-", "") || "";
   const codeString = String(children).replace(/\n$/, "");
 
   const handleCopy = async () => {
@@ -31,11 +30,6 @@ export function CodeBlock({ children, className, inline }: CodeBlockProps) {
 
   return (
     <div className="relative group my-4">
-      {language && (
-        <div className="absolute top-0 left-0 px-3 py-1 text-[10px] font-medium uppercase tracking-wider text-zinc-500 bg-black/30 rounded-tl-lg rounded-br-lg border-b border-r border-white/5">
-          {language}
-        </div>
-      )}
       <button
         onClick={handleCopy}
         className="absolute top-2 right-2 p-1.5 rounded-md bg-white/5 border border-white/10 text-zinc-500 hover:text-white hover:bg-white/10 transition-all opacity-0 group-hover:opacity-100 z-10"
@@ -47,7 +41,7 @@ export function CodeBlock({ children, className, inline }: CodeBlockProps) {
           <Copy className="w-3.5 h-3.5" />
         )}
       </button>
-      <pre className="overflow-x-auto rounded-lg bg-black/50 border border-white/10 p-4 pt-8 text-sm leading-relaxed font-mono scrollbar-thin">
+      <pre className="overflow-x-auto rounded-lg bg-black/50 border border-white/10 p-4 text-sm leading-relaxed font-mono scrollbar-thin">
         <code className={`text-zinc-300 ${className || ""}`}>{codeString}</code>
       </pre>
     </div>

apps/web/src/components/mermaid-diagram.tsx

@@ -1,7 +1,8 @@
 "use client";
 
-import { useEffect, useRef, useState } from "react";
+import { useEffect, useRef, useState, useCallback } from "react";
 import mermaid from "mermaid";
+import { Maximize2, Minimize2, ZoomIn, ZoomOut, RotateCcw } from "lucide-react";
 
 interface MermaidDiagramProps {
   chart: string;
@@ -11,6 +12,12 @@ export function MermaidDiagram({ chart }: MermaidDiagramProps) {
   const containerRef = useRef<HTMLDivElement>(null);
   const [error, setError] = useState<string | null>(null);
   const [isReady, setIsReady] = useState(false);
+  const [svgHtml, setSvgHtml] = useState<string>("");
+  const [isFullscreen, setIsFullscreen] = useState(false);
+  const [zoom, setZoom] = useState(1);
+  const [pan, setPan] = useState({ x: 0, y: 0 });
+  const [isPanning, setIsPanning] = useState(false);
+  const panStart = useRef({ x: 0, y: 0 });
 
   useEffect(() => {
     mermaid.initialize({
@@ -38,25 +45,85 @@ export function MermaidDiagram({ chart }: MermaidDiagramProps) {
   }, []);
 
   useEffect(() => {
-    if (!isReady || !containerRef.current || !chart) return;
+    if (!isReady || !chart) return;
 
     const renderChart = async () => {
       try {
         const id = `mermaid-${Math.random().toString(36).slice(2, 9)}`;
         const { svg } = await mermaid.render(id, chart);
-        
+        setSvgHtml(svg);
-        if (containerRef.current) {
+        setError(null);
-          containerRef.current.innerHTML = svg;
-          setError(null);
-        }
       } catch (err) {
-        setError(err instanceof Error ? err.message : "Failed to render diagram");
+        setError(
+          err instanceof Error ? err.message : "Failed to render diagram"
+        );
       }
     };
 
     renderChart();
   }, [chart, isReady]);
 
+  const handleWheel = useCallback((e: React.WheelEvent) => {
+    e.preventDefault();
+    const delta = e.deltaY > 0 ? -0.1 : 0.1;
+    setZoom((prev) => Math.min(Math.max(0.3, prev + delta), 5));
+  }, []);
+
+  const handleMouseDown = useCallback(
+    (e: React.MouseEvent) => {
+      if (e.button !== 0) return;
+      setIsPanning(true);
+      panStart.current = { x: e.clientX - pan.x, y: e.clientY - pan.y };
+    },
+    [pan]
+  );
+
+  const handleMouseMove = useCallback(
+    (e: React.MouseEvent) => {
+      if (!isPanning) return;
+      setPan({
+        x: e.clientX - panStart.current.x,
+        y: e.clientY - panStart.current.y,
+      });
+    },
+    [isPanning]
+  );
+
+  const handleMouseUp = useCallback(() => {
+    setIsPanning(false);
+  }, []);
+
+  const resetView = useCallback(() => {
+    setZoom(1);
+    setPan({ x: 0, y: 0 });
+  }, []);
+
+  const toggleFullscreen = useCallback(() => {
+    setIsFullscreen((prev) => !prev);
+    setZoom(1);
+    setPan({ x: 0, y: 0 });
+  }, []);
+
+  useEffect(() => {
+    if (!isFullscreen) return;
+    const handleKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape") setIsFullscreen(false);
+    };
+    window.addEventListener("keydown", handleKey);
+    return () => window.removeEventListener("keydown", handleKey);
+  }, [isFullscreen]);
+
+  useEffect(() => {
+    if (isFullscreen) {
+      document.body.style.overflow = "hidden";
+    } else {
+      document.body.style.overflow = "";
+    }
+    return () => {
+      document.body.style.overflow = "";
+    };
+  }, [isFullscreen]);
+
   if (error) {
     return (
       <div className="p-4 rounded-lg bg-red-500/10 border border-red-500/20">
@@ -66,17 +133,107 @@ export function MermaidDiagram({ chart }: MermaidDiagramProps) {
     );
   }
 
-  return (
+  const controls = (
+    <div className="flex items-center gap-1">
+      <button
+        onClick={() => setZoom((z) => Math.min(z + 0.25, 5))}
+        className="p-1.5 rounded-md text-zinc-500 hover:text-white hover:bg-white/10 transition-colors"
+        title="Zoom in"
+      >
+        <ZoomIn className="w-4 h-4" />
+      </button>
+      <span className="text-xs text-zinc-500 w-12 text-center tabular-nums">
+        {Math.round(zoom * 100)}%
+      </span>
+      <button
+        onClick={() => setZoom((z) => Math.max(z - 0.25, 0.3))}
+        className="p-1.5 rounded-md text-zinc-500 hover:text-white hover:bg-white/10 transition-colors"
+        title="Zoom out"
+      >
+        <ZoomOut className="w-4 h-4" />
+      </button>
+      <div className="w-px h-4 bg-white/10 mx-1" />
+      <button
+        onClick={resetView}
+        className="p-1.5 rounded-md text-zinc-500 hover:text-white hover:bg-white/10 transition-colors"
+        title="Reset view"
+      >
+        <RotateCcw className="w-4 h-4" />
+      </button>
+      <button
+        onClick={toggleFullscreen}
+        className="p-1.5 rounded-md text-zinc-500 hover:text-white hover:bg-white/10 transition-colors"
+        title={isFullscreen ? "Exit fullscreen" : "Fullscreen"}
+      >
+        {isFullscreen ? (
+          <Minimize2 className="w-4 h-4" />
+        ) : (
+          <Maximize2 className="w-4 h-4" />
+        )}
+      </button>
+    </div>
+  );
+
+  const diagramView = (fullHeight?: boolean) => (
     <div
-      ref={containerRef} 
+      className={`overflow-hidden ${isPanning ? "cursor-grabbing" : "cursor-grab"}`}
-      className="mermaid-diagram overflow-x-auto"
+      onWheel={handleWheel}
-      style={{ minHeight: "100px" }}
+      onMouseDown={handleMouseDown}
+      onMouseMove={handleMouseMove}
+      onMouseUp={handleMouseUp}
+      onMouseLeave={handleMouseUp}
+      style={fullHeight ? { height: "100%" } : { minHeight: "100px" }}
     >
-      {!isReady && (
+      <div
-        <div className="flex items-center justify-center py-8">
+        className="mermaid-diagram flex items-center justify-center"
-          <div className="w-6 h-6 border-2 border-blue-500/30 border-t-blue-500 rounded-full animate-spin" />
+        style={{
+          transform: `translate(${pan.x}px, ${pan.y}px) scale(${zoom})`,
+          transformOrigin: "center center",
+          transition: isPanning ? "none" : "transform 0.15s ease-out",
+          minHeight: fullHeight ? "100%" : "100px",
+        }}
+        dangerouslySetInnerHTML={svgHtml ? { __html: svgHtml } : undefined}
+      >
+        {!svgHtml && !isReady && (
+          <div className="flex items-center justify-center py-8">
+            <div className="w-6 h-6 border-2 border-blue-500/30 border-t-blue-500 rounded-full animate-spin" />
+          </div>
+        )}
+      </div>
+    </div>
+  );
+
+  if (isFullscreen) {
+    return (
+      <>
+        <div style={{ minHeight: "100px" }} />
+        <div className="fixed inset-0 z-50 bg-[#0a0a0f]/95 backdrop-blur-sm flex flex-col">
+          <div className="flex items-center justify-between px-6 py-3 border-b border-white/10">
+            <span className="text-sm text-zinc-400">Architecture Diagram</span>
+            {controls}
+          </div>
+          <div className="flex-1 overflow-hidden">
+            {diagramView(true)}
+          </div>
+          <div className="px-6 py-2 border-t border-white/10 text-center">
+            <span className="text-xs text-zinc-600">
+              Scroll to zoom · Drag to pan · Esc to close
+            </span>
+          </div>
         </div>
-      )}
+      </>
+    );
+  }
+
+  return (
+    <div className="relative">
+      <div className="flex items-center justify-end mb-2">{controls}</div>
+      {diagramView()}
+      <div className="mt-2 text-center">
+        <span className="text-xs text-zinc-600">
+          Scroll to zoom · Drag to pan
+        </span>
+      </div>
     </div>
   );
 }