iter(g03): 输入组件补 prefix/suffix 附加块

packages/skin/ui/ui.css

@@ -1608,3 +1608,42 @@ button.ua-step-dot:hover {
     transition: none !important;
   }
 }
+
+/* ---- 输入附加组（prefix/suffix） ---- */
+.ua-input-group {
+  display: inline-flex;
+  align-items: center;
+  border: 1px solid var(--ua-color-border);
+  border-radius: var(--ua-radius-md);
+  background: var(--ua-color-bg);
+  transition: border-color 0.15s, box-shadow 0.15s;
+}
+.ua-input-group:focus-within {
+  border-color: var(--ua-color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--ua-color-accent) 18%, transparent);
+}
+.ua-input-group .ua-input,
+.ua-input-group .ua-textarea {
+  border: none;           /* 组已带边框，内层去边防双线 */
+  border-radius: 0;
+  min-width: 160px;
+  background: transparent;
+}
+.ua-input-group .ua-input:focus,
+.ua-input-group .ua-textarea:focus {
+  box-shadow: none;       /* 聚焦光环由组统一承载 */
+  outline: none;
+}
+.ua-input-group-column {
+  flex-direction: column;
+  align-items: stretch;
+}
+.ua-input-addon {
+  display: inline-flex;
+  align-items: center;
+  padding: 6px 10px;
+  color: var(--ua-color-text-muted);
+  background: color-mix(in srgb, var(--ua-color-text) 5%, transparent);
+  font-size: var(--ua-font-size-md);
+  user-select: none;
+}