fix(comments): align Waline theme colors with site blue/orange theme

- Replace purple theme (#8B5CF6, #EC4899) with blue (#2563EB) and orange (#F97316)
- Use solid color for submit button instead of gradient

src/styles/waline-custom.css

@@ -5,9 +5,9 @@
 
 /* ========== 基础变量覆盖 ========== */
 :root {
-  /* 主题色 - 使用网站的紫色渐变accent */
-  --waline-theme-color: #8B5CF6;
-  --waline-active-color: #EC4899;
+  /* 主题色 - 使用网站的蓝色主题色 */
+  --waline-theme-color: #2563EB;
+  --waline-active-color: #F97316;
 
   /* 背景色 */
   --waline-bg-color: oklch(1 0 0);
@@ -23,7 +23,7 @@
   --waline-border-color: oklch(0.87 0 0);
 
   /* 其他颜色 */
-  --waline-badge-color: #8B5CF6;
+  --waline-badge-color: #2563EB;
   --waline-info-bg-color: oklch(0.97 0 0);
   --waline-info-color: oklch(0.55 0 0);
   --waline-bq-color: oklch(0.93 0 0);
@@ -109,18 +109,18 @@
 }
 
 .wl-btn.primary {
-  background: linear-gradient(135deg, #8B5CF6, #EC4899) !important;
+  background: #2563EB !important;
   border: none !important;
   color: white !important;
   font-weight: 500 !important;
 }
 
 .wl-btn.primary:hover {
-  background: linear-gradient(135deg, #7C3AED, #DB2777) !important;
+  background: #1D4ED8 !important;
   border: none !important;
   color: white !important;
   transform: translateY(-1px);
-  box-shadow: 0 4px 12px rgba(139, 92, 246, 0.3);
+  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
 }
 
 /* ========== 头部标签页 ========== */
@@ -156,7 +156,7 @@
 
 /* ========== 徽章样式 ========== */
 .wl-badge {
-  background: linear-gradient(135deg, #8B5CF6, #EC4899) !important;
+  background: linear-gradient(135deg, #2563EB, #F97316) !important;
   border: none !important;
   color: white !important;
   font-size: 0.7em !important;