pico/scss/themes/default/_dark.scss

// Dark theme (Auto)
// Automatically enabled if user has Dark mode enabled
@media only screen and (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {

    // Document
    --background:        #{darken($grey-900, 6%)};

    // Typography
    --text:              #{$grey-300};
    --h1:                #{$grey-50};
    --h2:                #{$grey-100};
    --h3:                #{$grey-200};
    --h4:                #{$grey-300};
    --h5:                #{$grey-400};
    --h6:                #{$grey-500};

    // Primary Call-to-Action and links
    --primary:           #{$primary-600};
    --primary-hover:     #{$primary-500};
    --primary-focus:     #{rgba($primary-600, .25)};
    --primary-inverse:   #{$white};

    // // Secondary Call-to-Action, links and kbd
    --secondary:         #{$grey-600};
    --secondary-hover:   #{$grey-500};
    --secondary-focus:   #{rgba($grey-600, .25)};
    --secondary-inverse: #{$white};

    // Contrast Call-to-Action and Tooltips
    --contrast:          #{$grey-100};
    --contrast-hover:    #{$white};
    --contrast-focus:    #{rgba($grey-600, .25)};
    --contrast-border:   #{rgba($amber-200, .33)}; // Links underline for
    --contrast-border-h: #{rgba($amber-200, .5)};  // Links hover underline
    --contrast-inverse:  #{darken($grey-900, 6%)};

    // Form elements
    --input-background:  #{darken($grey-900, 6%)};
    --input-border:      #{mix($grey-800, $grey-700)};

    // Utilities states
    --valid:             #{$green-700};
    --invalid:           #{$red-900};
    --mark:              #{rgba($amber-200, .5)};
    --mark-text:         #{$white};
    --muted-text:        #{$grey-500};
    --muted-background:  #{darken($grey-900, 6%)};
    --muted-border:      #{mix($grey-800, $grey-900)};

    // Card
    --card-background:   #{darken($grey-900, 2%)};
    --card-sections:     #{darken($grey-900, 4%)};
    --card-shadow:       0 0.125rem 1rem #{rgba($black, 0.08)}, 0 0.125rem 2rem #{rgba($black, 0.04)}, 0 0 0 0.0625rem #{rgba($black, 0.1)};

    // Code
    --code-background:   #{darken($grey-900, 4%)};
    --code-inlined:      #{rgba($grey-700, .25)};
    --code-color-1:      #{$grey-500};
    --code-color-2:      #{hsl(330, 30%, 50%)};
    --code-color-3:      #{hsl(185, 30%, 50%)};
    --code-color-4:      #{hsl(40,  10%, 50%)};
    --code-color-5:      #{mix($grey-600, $grey-700)};

    // Table
    --table-border:      #{darken($grey-900, 6%)};
    --table-stripping:   #{rgba($grey-500,.02)};
  }
}



// Dark theme (Forced)
// Enabled if forced with data-theme="dark"
[data-theme="dark"] {

  // Document
  --background:        #{darken($grey-900, 6%)};

  // Typography
  --text:              #{$grey-300};
  --h1:                #{$grey-50};
  --h2:                #{$grey-100};
  --h3:                #{$grey-200};
  --h4:                #{$grey-300};
  --h5:                #{$grey-400};
  --h6:                #{$grey-500};

  // Primary Call-to-Action and links
  --primary:           #{$primary-600};
  --primary-hover:     #{$primary-500};
  --primary-focus:     #{rgba($primary-600, .25)};
  --primary-inverse:   #{$white};

  // Secondary Call-to-Action, links and kbd
  --secondary:         #{$grey-600};
  --secondary-hover:   #{$grey-500};
  --secondary-focus:   #{rgba($grey-600, .25)};
  --secondary-inverse: #{$white};

  // Contrast Call-to-Action and Tooltips
  --contrast:          #{$grey-100};
  --contrast-hover:    #{$white};
  --contrast-focus:    #{rgba($grey-600, .25)};
  --contrast-border:   #{rgba($amber-200, .33)}; // For links
  --contrast-inverse:  #{darken($grey-900, 6%)};

  // Form elements
  --input-background:  #{darken($grey-900, 6%)};
  --input-border:      #{mix($grey-800, $grey-700)};

  // Utilities states
  --valid:             #{$green-700};
  --invalid:           #{$red-900};
  --mark:              #{rgba($amber-200, .5)};
  --mark-text:         #{$white};
  --muted-text:        #{$grey-500};
  --muted-background:  #{darken($grey-900, 6%)};
  --muted-border:      #{mix($grey-800, $grey-900)};

  // Card
  --card-background:   #{darken($grey-900, 2%)};
  --card-sections:     #{darken($grey-900, 4%)};
  --card-shadow:       0 0.125rem 1rem #{rgba($black, 0.08)}, 0 0.125rem 2rem #{rgba($black, 0.04)}, 0 0 0 0.0625rem #{rgba($black, 0.1)};

  // Code
  --code-background:   #{darken($grey-900, 4%)};
  --code-inlined:      #{rgba($grey-700, .25)};
  --code-color-1:      #{$grey-500};
  --code-color-2:      #{hsl(330, 30%, 50%)};
  --code-color-3:      #{hsl(185, 30%, 50%)};
  --code-color-4:      #{hsl(40,  10%, 50%)};
  --code-color-5:      #{mix($grey-600, $grey-700)};

  // Table
  --table-border:      #{darken($grey-900, 6%)};
  --table-stripping:   #{rgba($grey-500,.02)};
}