修改登录主页

src/components/Navbar.css

@@ -0,0 +1,90 @@
+.navbar {
+  background: white;
+  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
+  position: sticky;
+  top: 0;
+  z-index: 1000;
+}
+
+.navbar-inner {
+  max-width: 1200px;
+  margin: 0 auto;
+  padding: 12px 20px;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+}
+
+.logo {
+  margin-right: 16px;
+  color: #1890ff;
+  text-decoration: none;
+  font-weight: 600;
+}
+
+.navbar-left {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.nav-item {
+  position: relative;
+  padding: 8px 10px;
+}
+
+.nav-label {
+  color: #333;
+  cursor: default;
+}
+
+.nav-item:hover .dropdown {
+  display: block;
+}
+
+.dropdown {
+  display: none;
+  position: absolute;
+  top: 36px;
+  left: 0;
+  background: white;
+  border: 1px solid #e8e8e8;
+  box-shadow: 0 4px 16px rgba(0,0,0,0.1);
+  border-radius: 6px;
+  min-width: 160px;
+  padding: 6px 0;
+}
+
+.dropdown-item {
+  display: block;
+  padding: 8px 12px;
+  color: #333;
+  text-decoration: none;
+}
+
+.dropdown-item:hover {
+  background: #f5f5f5;
+}
+
+.navbar-right {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+}
+
+.search-input {
+  padding: 8px 12px;
+  border: 1px solid #d9d9d9;
+  border-radius: 4px;
+}
+
+.user-area {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+}
+
+.username {
+  color: #666;
+}
+