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+;;; leucosis-theme.el --- Ouroboros daylight theme with opalescent, pastel colors -*- lexical-binding:t
+
+;;; Commentary:
+;; This is a low contrast theme.
+
+;;; Code:
+
+;;; Helper functions for modifying colors
+(defun darken (hexcode %-lighter)
+  "Darken a hex code by a given %"
+  (let* ((code (string-remove-prefix "#" hexcode))
+	 (r-val (string-to-number (substring code 0 2) 16))
+	 (g-val (string-to-number (substring code 2 4) 16))
+	 (b-val (string-to-number (substring code 4 6) 16))
+	 (new-r (max 0 (round (- r-val (* r-val %-lighter)))))
+	 (new-g (max 0 (round (- g-val (* g-val %-lighter)))))
+	 (new-b (max 0 (round (- b-val (* b-val %-lighter))))))
+    (format "#%x%x%x" new-r new-g new-b)))
+
+(defun lighten (hexcode %-lighter)
+  "Lighten a hex code by a given %"
+  (let* ((code (string-remove-prefix "#" hexcode))
+	 (r-val (string-to-number (substring code 0 2) 16))
+	 (g-val (string-to-number (substring code 2 4) 16))
+	 (b-val (string-to-number (substring code 4 6) 16))
+	 (new-r (min 255 (round (+ r-val (* r-val %-lighter)))))
+	 (new-g (min 255 (round (+ g-val (* g-val %-lighter)))))
+	 (new-b (min 255 (round (+ b-val (* b-val %-lighter))))))
+    (format "#%x%x%x" new-r new-g new-b)))
+
+;;; Custom faces
+(defface fixed-pitch-scrawled '() "Fixed pitch face for scrawled text." :group 'basic-faces)
+
+(defface variable-pitch-serif '() "Variable pitch serif face." :group 'basic-faces)
+(defface variable-pitch-serif-text '() "Slightly larger variable pitch serif face." :group 'basic-faces)
+
+;;; Theme definition
+(deftheme leucosis
+  "Daylight theme from Ouroboros - opalescent, pastel colours on an off-white background."
+  :background-mode 'light
+  :contrast 'low)
+
+;; Color palette and settings
+(let (
+      ;; Fonts
+      (fixed-pitch-font "Monaspace Argon Frozen")
+      (fixed-pitch-alternative "Monaspace Radon Frozen ")
+      (fixed-pitch-serif "Monaspace Xenon Frozen")
+      (sans-serif-font "Ysabeau")
+      (serif-font "Crimson Pro")
+      
+      ;; Default, standard colors
+      (bg-main "#deeded")
+      (fg-main "#4d4d4d")
+      
+      ;; Accent colors
+      (accent-one "#c49672")
+      (accent-two "#8ca8d1")
+      (accent-three "#62c089")
+      (accent-four "#A85D92")
+      (accent-five "#CC9292")
+
+      ;; Extra saturated accents
+      (accent-one-saturated "#dc935b")
+      (accent-two-saturated "#77a3e4")
+      (accent-three-saturated "#49da85")
+      (accent-four-saturated "#cb399f")
+      (accent-five-saturated "#d85555")
+
+      ;; Desaturated accents
+      (accent-one-desaturated "#b49883")
+      (accent-two-desaturated "#98a9c2")
+      (accent-three-desaturated "#75ae8d")
+      (accent-four-desaturated "#996c8b")
+      (accent-five-desaturated "#ad8080")
+      )  
+  
+  (custom-theme-set-faces
+   'leucosis
+;;; Standard Text Faces
+   ;; Default
+   `(default ((t (:foreground ,fg-main :background ,bg-main :family ,fixed-pitch-font :weight semibold :height 98 :width semiexpanded))))
+   ;; Fixed pitch - the default fixed pitch setting here is Monaspace Radon, which can be used for comments
+   ;; Fixed pitch serif - Monaspace Xenon
+   `(fixed-pitch ((t (:foreground ,fg-main :background ,bg-main :family ,fixed-pitch-font :weight semibold :height 98 :width semiexpanded))))
+   `(fixed-pitch-scrawled ((t (:inheirt default :family ,fixed-pitch-alternative))))
+   `(fixed-pitch-serif ((t (:inherit default :family ,fixed-pitch-serif))))
+   ;; Variable pitch fonts - the default is sans serif Ysabeau, but we provide another face for serif fonts
+   `(variable-pitch ((t (:inherit default :family ,sans-serif-font :height 118))))
+   `(variable-pitch-text ((t (:inherit variable-pitch :height 138))))
+   `(variable-pitch-serif ((t (:inherit default :family ,serif-font :height 118))))
+   `(variable-pitch-serif-text ((t (:inherit variable-pitch-serif :height 138))))
+   ;; Shadow is just a lightened foreground
+   `(shadow ((t (:inherit default :foreground ,(lighten fg-main 0.7)))))
+
+;;; Highlighting
+   `(highlight ((t (:background ,(lighten accent-two-desaturated 0.3) :foreground ,(darken bg-main 0.4)))))
+   `(region ((t (:extend t :background ,(lighten accent-one-desaturated 0.3)))))
+   `(secondary-selection ((t (:inherit region :background ,(lighten accent-five-desaturated 0.3)))))
+   ;; trailing-whitespace
+   ;; escape-glyph
+   ;; homoglyph
+   ;; nobreak-space
+   ;; nobreak-hyphen
+   ;; isearch highlights
+   `(isearch ((t (:background ,accent-three :foreground ,bg-main))))
+   `(query-replace ((t (:inherit isearch :slant italic))))
+   `(lazy-highlight ((t (:inherit isearch :background ,accent-five-desaturated))))
+
+;;; Frame Appearance
+   `(cursor ((t (:background ,fg-main))))
+   `(fringe ((t (:background ,bg-main))))
+   ;; mouse
+   ;; tooltip
+   `(minibuffer-prompt ((t (:inherit default :foreground ,accent-two-saturated))))
+   `(vertical-border ((t (:foreground ,accent-one-saturated))))
+   ;;; Mode line and telephone
+   `(mode-line ((t (:background ,accent-one :foreground ,fg-main :box (:line-width (1 . -1) :color ,accent-one-saturated)))))
+   `(telephone-line-accent-active ((t (:inherit mode-line :background ,(darken fg-main 0.3) :foreground ,bg-main :box nil))))
+   `(mode-line-inactive ((t (:weight light :foreground ,bg-main :background ,accent-five))))
+   `(telephone-line-accent-inactive ((t (:inherit mode-line :background ,(lighten fg-main 0.3) :foreground ,bg-main :box nil))))
+   '(mode-line-buffer-id ((t (:weight bold))))
+   '(mode-line-emphasis ((t (:weight bold))))
+   `(mode-line-highlight ((t (:background ,accent-one-desaturated :box (:line-width (2 . 2) :color ,bg-main :style released-button)))))
+   `(mode-line-buffer-id ((t (:foreground ,accent-four-saturated))))
+   `(header-line ((t (:inherit mode-line))))
+   `(tab-line ((t (:inherit mode-line))))
+   ;; scroll-bar
+   ;; tool-bar
+   ;; tab-bar
+   ;; menu
+   ;; tty-menu-enabled, disabled, selected-face
+
+   ;;; Font lock faces
+   '(font-lock-bracket-face ((t (:inherit font-lock-punctuation-face))))
+   `(font-lock-builtin-face ((t (:foreground ,accent-four-saturated :weight bold))))
+   '(font-lock-comment-delimiter-face ((t (:inherit font-lock-comment-face))))
+   `(font-lock-comment-face ((t (:foreground ,accent-four-desaturated :family ,fixed-pitch-alternative :slant italic))))
+   `(font-lock-constant-face ((t (:foreground ,accent-three :weight bold))))
+   '(font-lock-delimiter-face ((t (:inherit font-lock-punctuation-face))))
+   '(font-lock-doc-face ((t (:inherit font-lock-string-face))))
+   '(font-lock-doc-markup-face ((t (:inherit font-lock-constant-face))))
+   '(font-lock-escape-face ((t (:inherit font-lock-regexp-grouping-backslash))))
+   '(font-lock-function-call-face ((t (:inherit font-lock-function-name-face))))
+   `(font-lock-function-name-face ((t (:foreground ,accent-one :slant italic))))
+   `(font-lock-keyword-face ((t (:foreground ,accent-two-saturated))))
+   '(font-lock-negation-char-face ((t nil)))
+   '(font-lock-number-face ((t nil)))
+   '(font-lock-misc-punctuation-face ((t (:inherit font-lock-punctuation-face))))
+   '(font-lock-operator-face ((t nil)))
+   '(font-lock-preprocessor-face ((t (:inherit font-lock-builtin-face))))
+   '(font-lock-property-name-face ((t (:inherit font-lock-variable-name-face))))
+   '(font-lock-property-use-face ((t (:inherit font-lock-property-name-face))))
+   '(font-lock-punctuation-face ((t nil)))
+   '(font-lock-regexp-grouping-backslash ((t (:inherit bold))))
+   '(font-lock-regexp-grouping-construct ((t (:inherit bold))))
+   `(font-lock-string-face ((t (:foreground ,(darken accent-five 0.3)))))
+   `(font-lock-type-face ((t (:foreground ,accent-two))))
+   `(font-lock-variable-name-face ((t (:foreground ,(darken accent-one 0.3)))))
+   '(font-lock-variable-use-face ((t (:inherit font-lock-variable-name-face))))
+   '(font-lock-warning-face ((t (:inherit error))))
+   `(error ((t (:foreground ,accent-five-saturated :weight black))))
+
+   ;;; Rainbow delimiters
+   `(rainbow-delimiters-depth-1-face ((t (:foreground ,accent-two-saturated :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-2-face ((t (:foreground ,accent-four-saturated  :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-3-face ((t (:foreground ,accent-one-saturated  :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-4-face ((t (:foreground ,accent-three-saturated  :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-5-face ((t (:foreground ,accent-five  :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-6-face ((t (:foreground ,accent-two :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-7-face ((t (:foreground ,accent-four :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-8-face ((t (:foreground ,accent-one :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-depth-9-face ((t (:foreground ,accent-three :inherit rainbow-delimiters-base-face))))
+   `(rainbow-delimiters-base-error-face ((t (:foreground ,accent-five-saturated :inherit rainbow-delimiters-base-face :weight black))))
+
+   ;;; Treemacs
+   `(treemacs-directory-face ((t (:inherit font-lock-function-name-face :foreground ,(darken accent-one 0.2)))))
+   `(treemacs-root-face ((t (:underline t :weight bold :height 1.4 :family ,fixed-pitch-serif :foreground ,(darken accent-three 0.4)))))
+
+   ;;; Magit
+   `(magit-diff-added ((t (:background ,(lighten accent-three 0.3) :foreground ,(darken accent-three-saturated 0.5)))))
+   `(magit-diff-removed ((t (:background ,(lighten accent-five 0.3) :foreground ,(darken accent-five-saturated 0.5)))))
+   `(magit-diff-context-highlight ((t (:inherit default :extend t :background ,(lighten bg-main 0.05) :foreground ,(lighten fg-main 0.2)))))
+   `(magit-section-highlight ((t (:extend t :background ,(lighten bg-main 0.05)))))
+   `(magit-section-heading ((t (:extend t :background ,(darken bg-main 0.05) :foreground ,(darken accent-four-saturated 0.1) :weight bold))))
+
+;;; Org mode and org modern
+   `(org-document-title ((t (:inherit variable-pitch-serif-text :height 1.6))))
+   `(org-document-info ((t (:inherit variable-pitch-serif-text :height 0.9 :foreground ,(darken accent-one 0.3)))))
+   `(org-document-info-keyword ((t (:inherit variable-pitch-text :foreground ,accent-two-desaturated))))
+   ;; Outline faces
+   `(outline-1 ((t (:inherit variable-pitch-serif :height 1.3 :foreground ,(darken accent-one-desaturated 0.3)))))
+   `(outline-2 ((t (:inherit variable-pitch-serif :height 1.2 :foreground ,(darken accent-two-desaturated 0.3)))))
+   `(outline-3 ((t (:inherit variable-pitch-serif :height 1.1 :foreground ,(darken accent-three-desaturated 0.3)))))
+   `(outline-4 ((t (:inherit variable-pitch-serif :height 1.0 :foreground ,(darken accent-four-desaturated 0.3)))))
+   `(outline-5 ((t (:inherit variable-pitch-serif :height 0.9 :foreground ,(darken accent-five-desaturated 0.3)))))
+   `(outline-6 ((t (:inherit variable-pitch-serif :height 0.8 :foreground ,(darken accent-one-desaturated 0.6)))))
+   `(outline-7 ((t (:inherit variable-pitch-serif :height 0.7 :foreground ,(darken accent-two-desaturated 0.6)))))
+   `(outline-8 ((t (:inherit variable-pitch-serif :height 0.6 :foreground ,(darken accent-three-desaturated 0.6)))))
+   ;; Todos and Labels
+   `(org-todo ((t (:inherit variable-pitch :weight bold :foreground ,(darken accent-five-saturated 0.1)))))
+   `(org-done ((t (:inherit variable-pitch :weight bold :background ,(darken accent-three-saturated 0.1) :foreground ,bg-main))))
+   `(org-modern-done ((t (:inherit org-done))))
+   `(org-modern-tag ((t (:extend t :foreground ,bg-main :background ,accent-two))))
+   ;; Drawers and blocks
+   `(org-drawer ((t (:inherit fixed-pitch-serif :height 0.6 :foreground ,(darken accent-two-desaturated 0.2)))))
+   `(org-special-keyword ((t (:inherit fixed-pitch-serif :height 0.6 :foreground ,(darken accent-two 0.2)))))
+   `(org-property-value ((t (:inherit default :height 0.6 :foreground ,(darken accent-two-desaturated 0.2)))))
+   `(org-block-begin-line ((t (:family ,fixed-pitch-serif :height 0.8 :foreground ,(darken accent-one-desaturated 0.2)))))
+   `(org-meta-line ((t (:inheirt org-block-begin-line))))
+   `(org-block ((t (:inherit fixed-pitch))))
+   ;; Code and literal
+   `(org-code ((t (:family ,fixed-pitch-font :weight semibold :height 0.8 :foreground ,(lighten fg-main 0.2)))))
+   `(org-verbatim ((t (:family ,fixed-pitch-font :weight semibold :foreground ,(darken accent-two-saturated 0.2)))))
+   ;; Indentation
+   `(org-indent ((t (:inherit (org-hide fixed-pitch)))))
+   ;; Tables
+   `(org-table ((t (:inherit fixed-pitch :foreground ,(lighten fg-main 0.1)))))
+
+   ;;; Company Mode
+   `(company-tooltip ((t (:inherit fixed-pitch :background ,accent-one :foreground ,bg-main))))
+   `(company-tooltip-common ((t (:foreground ,(darken accent-four 0.2)))))
+   )
+
+  (custom-theme-set-variables
+   'leucosis
+   '(icon-preference '(symbol image emoji text))
+   `(beacon-color ,accent-two)
+   '(org-hidden-keywords t)
+   '(company-format-margin-function #'company-text-icons-margin))
+
+  (provide-theme 'leucosis))
+
+;;; leucosis-theme.el ends here