插件下载页面：扩大窄屏设备抽屉大小

[northword]

https://github.com/zotero-chinese/website/blob/main/src%2F.vitepress%2Ftheme%2Fcomponents%2FPluginDownloadModal.vue#L23

if (window.screen.width < 500) {
  // 当前设备是移动设备，80%
} else {
  // 现有值
}