Claude.ai theme for Markdown Viewer browser extension

claude-theme.css

/* Claude.ai Theme for Markdown Viewer */
/* https://github.com/simov/markdown-viewer */

/* ── Fonts ── */

@font-face {
  font-family: anthropicSerif;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/fe66948be403232d-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: normal;
}

@font-face {
  font-family: anthropicSerif;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/56139cc7a3934d47-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: italic;
}

@font-face {
  font-family: anthropicSans;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/01d1396bd69a228a-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: normal;
}

@font-face {
  font-family: anthropicSans;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/8d6f5db32d507c08-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: italic;
}

@font-face {
  font-family: anthropicMono;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/5ab84f5ed5bd55bd-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: normal;
}

@font-face {
  font-family: anthropicMono;
  src: url(https://assets-proxy.anthropic.com/claude-ai/v1/_next/static/media/c25fe61b276783b5-s.p.woff2) format("woff2");
  font-display: swap;
  font-weight: 300 800;
  font-style: italic;
}

/* ── Light Mode (default) ── */

@media (prefers-color-scheme: light) {
  body {
    color: hsl(60 2.6% 7.6%);
    background: hsl(48 33.3% 97.1%);
  }

  a { color: hsl(210 73.7% 40.2%); }
  a:hover { color: hsl(210 70.9% 51.6%); }

  hr {
    border-color: hsl(30 3.3% 11.8% / 0.3);
  }

  blockquote {
    border-left-color: hsl(30 3.3% 11.8% / 0.3);
    background: hsl(48 33.3% 97.1%);
  }

  code:not([class^="language-"]):not([class^="hljs"]) {
    background: hsl(48 33.3% 97.1%);
    color: hsl(60 2.6% 7.6%);
  }

  pre {
    background: #282c34;
  }

  table th {
    color: hsl(60 2.6% 7.6%);
    border-bottom-color: hsl(30 3.3% 11.8% / 0.6);
  }

  table td {
    border-bottom-color: hsl(30 3.3% 11.8% / 0.3);
  }

  table tr:nth-child(even) td {
    background: hsl(48 33.3% 97.1%);
  }
}

/* ── Dark Mode ── */

@media (prefers-color-scheme: dark) {
  body {
    color: hsl(48 33.3% 97.1%);
    background: hsl(60 2.1% 18.4%);
  }

  a { color: hsl(210 65.5% 67.1%); }
  a:hover { color: hsl(210 70.9% 51.6%); }

  strong, b { font-weight: 530; }

  hr {
    border-color: hsl(51 16.5% 84.5% / 0.3);
  }

  blockquote {
    border-left-color: hsl(51 16.5% 84.5% / 0.3);
    background: hsl(60 2.7% 14.5%);
  }

  code:not([class^="language-"]):not([class^="hljs"]) {
    background: hsl(60 2.7% 14.5%);
    color: hsl(48 33.3% 97.1%);
  }

  pre {
    background: #282c34;
  }

  table th {
    color: hsl(48 33.3% 97.1%);
    border-bottom-color: hsl(51 16.5% 84.5% / 0.6);
  }

  table td {
    border-bottom-color: hsl(51 16.5% 84.5% / 0.3);
  }

  table tr:nth-child(even) td {
    background: hsl(60 2.7% 14.5%);
  }
}

/* ── Base ── */

body {
  font-family: anthropicSerif, Georgia, "Times New Roman", Times, serif;
  font-weight: 400;
  line-height: 1.7;
  max-width: 48rem;
  margin: 0 auto;
  padding: 1.5rem 2.75rem;
}

/* ── Headings ── */

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  margin-top: 1.5rem;
  margin-bottom: 0.25rem;
}

h1 {
  font-size: 1.375rem;
  margin-top: 0.75rem;
}

h2 {
  font-size: 1.125rem;
  margin-top: 0.75rem;
}

h3 {
  font-size: 1rem;
  margin-top: 0.5rem;
}

h4 {
  font-size: 0.875rem;
}

/* ── Paragraph ── */

p {
  margin: 0;
  line-height: 1.7;
  overflow-wrap: break-word;
}

p + p {
  margin-top: 0.875rem;
}

/* ── Links ── */

a {
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* ── Bold / Italic ── */

strong, b {
  font-weight: 600;
}

/* ── Horizontal Rule ── */

hr {
  border: none;
  border-top: 0.5px solid;
  margin: 0.75rem 0.375rem;
}

/* ── Lists ── */

ul {
  list-style-type: disc;
  padding-left: 2rem;
  margin: 0 0 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

ol {
  list-style-type: decimal;
  padding-left: 2rem;
  margin: 0 0 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

li {
  padding-left: 0.5rem;
  overflow-wrap: break-word;
}

li ul, li ol {
  margin-top: 0.25rem;
  margin-bottom: 0;
}

/* ── Blockquote ── */

blockquote {
  border-left: 3px solid;
  padding: 0.25rem 1rem;
  margin: 0.75rem 0;
}

blockquote p {
  margin: 0.25rem 0;
}

/* ── Inline Code ── */

code:not([class^="language-"]):not([class^="hljs"]) {
  font-family: anthropicMono, ui-monospace, SFMono-Regular, Menlo, Monaco, monospace;
  font-size: 0.813rem;
  line-height: 1.5;
  border-radius: 0.25rem;
  padding: 0.125rem 0.375rem;
  font-weight: 400;
}

/* ── Code Block ── */

pre {
  border-radius: 0.75rem;
  padding: 1rem;
  margin: 0.5rem 0;
  overflow-x: auto;
}

pre code {
  font-family: anthropicMono, ui-monospace, SFMono-Regular, Menlo, Monaco, monospace;
  font-size: 0.813rem;
  line-height: 1.5;
  font-weight: 400;
  background: none;
  padding: 0;
}

/* ── Table ── */

table {
  min-width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  line-height: 1.7;
  margin: 0.5rem 0 1.5rem;
}

thead {
  text-align: left;
}

th {
  font-weight: 600;
  padding: 0.5rem 1rem 0.5rem 0;
  border-bottom-width: 0.5px;
  border-bottom-style: solid;
  vertical-align: top;
  text-align: left;
}

td {
  padding: 0.5rem 1rem 0.5rem 0;
  border-bottom-width: 0.5px;
  border-bottom-style: solid;
  vertical-align: top;
}

/* ── Image ── */

img {
  max-width: 100%;
  height: auto;
  border-radius: 0.5rem;
}

/* ── Syntax Highlighting (One Dark) ── */

pre code.hljs { display: block; overflow-x: auto; padding: 1em; }
code.hljs { padding: 3px 5px; }
.hljs { color: #abb2bf; background: #282c34; }
.hljs-comment, .hljs-quote { color: #5c6370; font-style: italic; }
.hljs-doctag, .hljs-formula, .hljs-keyword { color: #c678dd; }
.hljs-deletion, .hljs-name, .hljs-section, .hljs-selector-tag, .hljs-subst { color: #e06c75; }
.hljs-literal { color: #56b6c2; }
.hljs-addition, .hljs-attribute, .hljs-meta .hljs-string, .hljs-regexp, .hljs-string { color: #98c379; }
.hljs-attr, .hljs-number, .hljs-selector-attr, .hljs-selector-class, .hljs-selector-pseudo, .hljs-template-variable, .hljs-type, .hljs-variable { color: #d19a66; }
.hljs-bullet, .hljs-link, .hljs-meta, .hljs-selector-id, .hljs-symbol, .hljs-title { color: #61aeee; }
.hljs-built_in, .hljs-class .hljs-title, .hljs-title.class_ { color: #e6c07b; }
.hljs-emphasis { font-style: italic; }
.hljs-strong { font-weight: 700; }
.hljs-link { text-decoration: underline; }

/* ── Content Spacing (mimics Claude's grid gap) ── */

body > * + * {
  margin-top: 0.875rem;
}

body > hr + h1,
body > hr + h2,
body > hr + h3,
body > hr + h4 {
  margin-top: 0 !important;
}