恢复使用login.png作为登录页面背景图片

demo/frontend/src/views/Login.vue

@@ -207,9 +207,7 @@ const handleLogin = async () => {
   min-height: 100vh;
   width: 100vw;
   height: 100vh;
-  background: 
-    radial-gradient(ellipse at top right, rgba(0, 100, 200, 0.3) 0%, transparent 50%),
-    linear-gradient(135deg, #0a0a0a 0%, #1a1a2e 50%, #16213e 100%);
+  background: url('/images/backgrounds/login.png') center/cover no-repeat;
   position: fixed;
   top: 0;
   left: 0;
@@ -219,33 +217,6 @@ const handleLogin = async () => {
   padding: 0;
 }
 
-/* 添加动态光效 */
-.login-page::before {
-  content: '';
-  position: absolute;
-  top: 0;
-  right: 0;
-  width: 60%;
-  height: 100%;
-  background: 
-    linear-gradient(45deg, transparent 0%, rgba(0, 150, 255, 0.1) 20%, rgba(0, 200, 255, 0.2) 40%, transparent 60%),
-    radial-gradient(ellipse at top right, rgba(0, 150, 255, 0.3) 0%, transparent 70%);
-  animation: lightStreak 8s ease-in-out infinite alternate;
-  pointer-events: none;
-  z-index: 1;
-}
-
-@keyframes lightStreak {
-  0% { 
-    opacity: 0.3; 
-    transform: translateX(0px) scale(1);
-  }
-  100% { 
-    opacity: 0.7; 
-    transform: translateX(-20px) scale(1.05);
-  }
-}
-
 /* 背景效果已移除，使用图片背景 */
 
 /* 左上角Logo */