refactor: unify floating toolbar sizing and show graph title

src/components/ui/icon-button.module.css

@@ -3,8 +3,9 @@
   align-items: center;
   justify-content: center;
   flex: 0 0 auto;
-  width: 28px;
-  height: 24px;
+  box-sizing: border-box;
+  width: var(--toolbar-control-width, 28px);
+  height: var(--toolbar-control-height, 24px);
   padding: 4px 6px;
   border: 0;
   border-radius: 5px;
@@ -12,7 +13,7 @@
   color: inherit;
   cursor: pointer;
 }
-.button svg { width: 16px; height: 16px; flex: 0 0 16px; }
+.button svg { width: var(--toolbar-icon-size, 16px); height: var(--toolbar-icon-size, 16px); flex: 0 0 var(--toolbar-icon-size, 16px); }
 .button:hover { background: #e9e7e3; }
 .button:focus-visible { outline: 2px solid #9d7d66; outline-offset: 2px; }
 .button:disabled { opacity: 0.45; cursor: not-allowed; }

src/components/ui/toolbar.module.css

@@ -0,0 +1,18 @@
+.surface {
+  --toolbar-icon-size: 16px;
+  --toolbar-control-width: 28px;
+  --toolbar-control-height: 24px;
+  display: flex;
+  align-items: center;
+  gap: 2px;
+  padding: 4px;
+  border: 1px solid #e2dcd3;
+  border-radius: 8px;
+  background: #fffffff5;
+  color: #4b443d;
+  box-shadow: 0 3px 14px #32251a0a;
+  backdrop-filter: blur(12px);
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
+  font-size: 12px;
+  line-height: 20px;
+}