功能增加

app/globals.css

@@ -4422,8 +4422,35 @@ h3 {
   margin-left: auto;
 }
 
+.image-size-hint {
+  color: var(--muted);
+  font-size: 10px;
+  line-height: 1.4;
+}
+
+.seedream-view-controls {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 3px;
+}
+
+.seedream-zoom-level {
+  min-width: 42px;
+  text-align: center;
+  color: var(--muted-strong);
+  font-size: 11px;
+  font-variant-numeric: tabular-nums;
+}
+
+.seedream-view-error {
+  color: var(--danger);
+  font-size: 12px;
+}
+
 .seedream-canvas-viewport {
   --seedream-canvas-height: clamp(280px, 38vh, 460px);
+  position: relative;
   width: 100%;
   height: var(--seedream-canvas-height);
   min-height: 0;
@@ -4431,6 +4458,8 @@ h3 {
   display: grid;
   place-items: center;
   overflow: hidden;
+  touch-action: none;
+  overscroll-behavior: contain;
   padding: 10px;
   border: 1px solid var(--line);
   border-radius: 10px;
@@ -4445,21 +4474,71 @@ h3 {
 }
 
 .seedream-canvas-stage {
-  position: relative;
-  width: fit-content;
-  max-width: 100%;
+  position: absolute;
+  left: 50%;
+  top: 50%;
+  transform-origin: center;
   line-height: 0;
   box-shadow: 0 12px 30px rgba(15, 23, 42, 0.13);
 }
 
 .seedream-canvas-stage > img {
-  width: auto;
-  max-width: 100%;
-  max-height: calc(var(--seedream-canvas-height) - 22px);
+  width: 100%;
+  height: 100%;
+  max-width: none;
+  max-height: none;
   display: block;
   user-select: none;
 }
 
+.seedream-canvas-viewport:focus-visible {
+  outline: 2px solid var(--green);
+  outline-offset: 2px;
+}
+
+.seedream-canvas-viewport.pan-ready,
+.seedream-canvas-viewport.pan-ready .seedream-annotation-canvas,
+.seedream-canvas-viewport.pan-ready .seedream-annotation-shape {
+  cursor: grab;
+}
+
+.seedream-canvas-viewport.panning,
+.seedream-canvas-viewport.panning .seedream-annotation-canvas,
+.seedream-canvas-viewport.panning .seedream-annotation-shape {
+  cursor: grabbing;
+}
+
+/* Native fullscreen promotes this same editor to the top layer. No duplicate
+   canvas, nested modal, backdrop blur, or lost annotation state. */
+.seedream-workspace:fullscreen {
+  width: 100%;
+  height: 100%;
+  min-height: 0;
+  margin: 0;
+  padding: 16px;
+  border: 0;
+  border-radius: 0;
+  overflow: hidden;
+}
+
+.seedream-workspace:fullscreen .seedream-canvas-viewport {
+  height: auto;
+  min-height: 120px;
+  flex: 1 1 auto;
+}
+
+.seedream-workspace:fullscreen .seedream-source-picker {
+  flex: 0 0 auto;
+  max-height: 145px;
+  overflow-y: auto;
+}
+
+.seedream-canvas-note > span {
+  display: block;
+  margin-bottom: 3px;
+  color: var(--green-dark);
+}
+
 .seedream-annotation-canvas {
   position: absolute;
   inset: 0;