样式优化，markdown优化

frontend/src/components/MarkdownRenderer.vue

@@ -0,0 +1,17 @@
+<template>
+  <div class="markdown-renderer" v-html="html"></div>
+</template>
+
+<script setup lang="ts">
+import { computed } from 'vue';
+import { renderMarkdown } from '@/utils/markdown';
+
+const props = defineProps<{ content?: string }>();
+const html = computed(() => renderMarkdown(props.content ?? ''));
+</script>
+
+<style scoped>
+.markdown-renderer { color: var(--text-color); line-height:1.6; word-break:break-word; }
+.markdown-renderer pre { background:var(--code-bg,#0b1220); color:var(--code-color,#e6edf3); padding:12px; border-radius:8px; overflow:auto; }
+.markdown-renderer code { background:rgba(0,0,0,0.04); padding:2px 6px; border-radius:4px; font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, "Roboto Mono", "Noto Mono", monospace; }
+</style>