custom_twitter_card.html

<!-- Modified from _internal/twitter_card.html -->
{{ if .IsPage }}
  {{ with .Params.twitterImage }}
  <!-- The Open Graph protocol data -->
    <meta property="og:image" content="{{ print $.Site.BaseURL . }}"/>
  <!-- Twitter summary card with large image must be at least 280x150px -->
    <meta name="twitter:card" content="summary_large_image"/>
    <meta name="twitter:image:src" content="{{ print $.Site.BaseURL . }}"/>
  {{ else }}
    <meta name="twitter:card" content="summary"/>
  {{ end }}
  <!-- The Open Graph protocol data -->
  <meta property="og:url" content="{{ $.Permalink }}"/>
  <meta property="og:type" content="article"/>
  <meta property="og:title" content="{{ print .Title " - " .Site.Title }}"/>
  <meta property="og:description" content="{{ with .Description }}{{ . }}{{ else }}{{ if .IsPage }}{{ .Summary }}{{ else }}{{ with .Site.Params.description }}{{ . }}{{ end }}{{ end }}{{ end }}"/>
  <!-- Twitter Card data -->
  <meta name="twitter:title" content="{{ print .Title " - " .Site.Title }}"/>
  <meta name="twitter:description" content="{{ with .Description }}{{ . }}{{ else }}{{ if .IsPage }}{{ .Summary }}{{ else }}{{ with .Site.Params.description }}{{ . }}{{ end }}{{ end }}{{ end }}"/>
  {{ with .Site.Params.twitterCardSite }}<meta name="twitter:site" content="@{{ . }}"/>{{ end }}
  {{ with .Site.Params.twitterCardDomain }}<meta name="twitter:domain" content="{{ . }}"/>{{ end }}
  {{ with .Site.Params.twitterCardAuthor }}<meta name="twitter:creator" content="@{{ . }}"/>{{ end }}
{{ end }}