feat: init Astro blog with wikilinks, KaTeX and local search

- Astro 5 static blog, zero runtime JS
- Obsidian wikilink remark plugin (slug matches Astro content collection)
- KaTeX math rendering, local search, TOC, archives, tags
- 5 posts on math/physics/ML topics
- deploy scripts for nginx + certbot + rsync

src/styles/prose.css

@@ -0,0 +1,137 @@
+/* ==========================================================================
+   文章正文排版 · prose
+   ========================================================================== */
+.prose {
+  font-size: clamp(1rem, 0.4rem + 1.6vw, 1.125rem);
+  line-height: 1.85;
+  color: var(--ink);
+  word-wrap: break-word;
+  overflow-wrap: break-word;
+}
+.prose > * + * { margin-top: 1.4em; }
+
+/* 标题 */
+.prose h2, .prose h3, .prose h4 {
+  font-family: var(--font-display);
+  font-weight: 800;
+  letter-spacing: -0.02em;
+  scroll-margin-top: calc(var(--nav-h) + 24px);
+}
+.prose h2 {
+  font-size: clamp(1.4rem, 1rem + 1.8vw, 1.75rem);
+  margin-top: 2.2em;
+  padding-bottom: .4em;
+  border-bottom: 1px solid rgba(79,163,255,.25);
+  position: relative;
+}
+.prose h2::before {
+  content: '';
+  display: inline-block;
+  width: 5px; height: 1em;
+  margin-right: 12px;
+  vertical-align: -0.05em;
+  border-radius: 6px;
+  background: linear-gradient(180deg, var(--blue-500), var(--cyan-400));
+}
+.prose h3 {
+  font-size: clamp(1.2rem, 0.9rem + 1.2vw, 1.4rem);
+  margin-top: 1.8em;
+  color: var(--ink);
+}
+.prose h4 { font-size: 1.05rem; margin-top: 1.6em; }
+
+.prose p { color: var(--ink); }
+.prose a { color: var(--blue-600); text-decoration: underline; text-decoration-color: rgba(47,127,224,.35); text-underline-offset: 3px; }
+.prose a:hover { text-decoration-color: var(--blue-500); }
+
+/* 列表 */
+.prose ul, .prose ol { padding-left: 1.4em; }
+.prose ul { list-style: disc; }
+.prose ol { list-style: decimal; }
+.prose li { margin-top: .4em; }
+.prose li::marker { color: var(--blue-500); }
+
+/* 引用 */
+.prose blockquote {
+  padding: 1em 1.4em;
+  margin: 1.6em 0;
+  border-left: 4px solid var(--blue-400);
+  border-radius: 0 var(--r-md) var(--r-md) 0;
+  background: linear-gradient(90deg, rgba(132,194,255,.12), transparent);
+  color: var(--ink-soft);
+  font-style: normal;
+}
+.prose blockquote p { color: var(--ink-soft); }
+
+/* 代码 */
+.prose :not(pre) > code {
+  font-family: var(--font-mono);
+  font-size: 0.88em;
+  padding: 2px 7px;
+  border-radius: 6px;
+  background: rgba(47,127,224,.12);
+  color: var(--blue-700);
+  border: 1px solid rgba(47,127,224,.18);
+  word-break: break-word;
+}
+.prose pre {
+  padding: 1.15em 1.4em;
+  border-radius: var(--r-md);
+  overflow-x: auto;
+  border: 1px solid var(--glass-border);
+  background: rgba(255,255,255,.62);
+  backdrop-filter: blur(14px);
+  -webkit-backdrop-filter: blur(14px);
+  box-shadow: var(--glass-shadow);
+  font-size: 0.88rem;
+  line-height: 1.7;
+}
+.prose pre code { font-family: var(--font-mono); background: none; border: 0; padding: 0; color: inherit; }
+
+/* 行内元素 */
+.prose strong { font-weight: 800; color: var(--ink); }
+.prose em { font-style: italic; }
+.prose del { color: var(--ink-faint); }
+.prose mark { background: var(--blue-200); color: var(--ink); padding: 1px 4px; border-radius: 4px; }
+.prose kbd {
+  font-family: var(--font-mono);
+  font-size: .85em;
+  padding: 2px 6px;
+  border-radius: 6px;
+  background: #fff;
+  border: 1px solid var(--blue-200);
+  box-shadow: 0 2px 0 var(--blue-200);
+}
+
+/* 分割线 */
+.prose hr { height: 1px; border: 0; margin: 2.4em 0; background: linear-gradient(90deg, transparent, rgba(79,163,255,.3), transparent); }
+
+/* 图片 */
+.prose img {
+  border-radius: var(--r-md);
+  border: 1px solid var(--glass-border);
+  box-shadow: var(--glass-shadow);
+  margin: 1.6em auto;
+}
+
+/* 表格 */
+.prose table { width: 100%; margin: 1.6em 0; font-size: .92em; overflow-x: auto; display: block; }
+.prose thead { background: rgba(132,194,255,.18); }
+.prose th, .prose td { padding: .6em .9em; border: 1px solid rgba(79,163,255,.25); text-align: left; }
+.prose tbody tr:nth-child(even) { background: rgba(132,194,255,.06); }
+
+/* 移动端：代码块横向滚动不撑破布局 */
+@media (max-width: 768px) {
+  .prose pre { font-size: 0.82rem; padding: 1em; }
+  .prose table { font-size: 0.85rem; }
+}
+
+/* KaTeX 数学公式 */
+.prose .katex { font-size: 1.05em; }
+.prose .katex-display {
+  margin: 1.4em 0;
+  padding: 0.6em 0.2em;
+  overflow-x: auto;
+  overflow-y: hidden;
+}
+.prose .katex-display > .katex { font-size: 1.15em; }