初始提交：短剧库源码（含转码优化 ultrafast）

internal/webui/theme.js

@@ -0,0 +1,23 @@
+(() => {
+  const system = window.matchMedia('(prefers-color-scheme: dark)');
+  let preference = 'system';
+  try {preference = localStorage.getItem('duanju.theme') || 'system';} catch (_) {}
+  if (!['system', 'light', 'dark'].includes(preference)) preference = 'system';
+  function apply() {
+    const theme = preference === 'system' ? (system.matches ? 'dark' : 'light') : preference;
+    document.documentElement.dataset.theme = theme;
+    const browserColor = document.querySelector('meta[name="theme-color"]');
+    if (browserColor) browserColor.content = theme === 'dark' ? '#161b19' : '#f7f7f2';
+    document.dispatchEvent(new CustomEvent('themechange', {detail: preference}));
+  }
+  function set(value) {
+    if (!['system', 'light', 'dark'].includes(value)) return;
+    preference = value;
+    try {localStorage.setItem('duanju.theme', value);} catch (_) {}
+    apply();
+  }
+  if (system.addEventListener) system.addEventListener('change', apply);
+  else system.addListener(apply);
+  window.JukuTheme = {set, get: () => preference};
+  apply();
+})();