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+;;; oni-css.el --- CSS configuration                 -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2019  Tom Willemse
+
+;; Author: Tom Willemse <tom@ryuslash.org>
+;; Keywords: local
+;; Version: 20190218233500
+;; Package-Requires: (oni-company hydra fill-column-indicator)
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Configuration for `css-mode' and `scss-mode'.
+
+;;; Code:
+
+(require 'align)
+(require 'css-mode)
+(require 'hydra)
+
+(eval-when-compile
+  (require 'compile))
+
+(defun oni-css-property-important-p ()
+  "Return whether or not the current property is important."
+  (save-excursion
+    (beginning-of-line)
+    (re-search-forward "!important" (line-end-position) :noerror)))
+
+(defun oni-css-add-important ()
+  "Add an important flag to the property on the current line."
+  (interactive)
+  (unless (oni-css-property-important-p)
+    (save-excursion
+      (end-of-line)
+      (when (re-search-backward ";" (line-beginning-position) :noerror)
+        (insert " !important")))))
+
+(defun oni-css-remove-important ()
+  "Remove the important flag from the property on the current line."
+  (interactive)
+  (when (oni-css-property-important-p)
+    (save-excursion
+      (end-of-line)
+      (when (re-search-backward " !important" (line-beginning-position) :noerror)
+        (replace-match "")))))
+
+(defun oni-css-mode-init--toggle-important ()
+  "Toggle the important flag on the property on the current line."
+  (interactive)
+  (if (oni-css-property-important-p)
+      (oni-css-remove-important)
+    (oni-css-add-important)))
+
+(defhydra css-mode-hydra (:color blue)
+  ("!" oni-css-mode-init--toggle-important))
+
+(setq css-indent-offset 2)
+
+(add-hook 'css-mode-hook 'electric-pair-local-mode)
+(add-hook 'css-mode-hook 'electric-indent-local-mode)
+(add-hook 'css-mode-hook 'company-mode)
+(add-hook 'css-mode-hook 'fci-mode)
+
+(with-eval-after-load 'compile
+  (let ((scss-error-regexp
+         (rx (and bol
+                  (zero-or-more space) "on line "
+                  (group (one-or-more digit)) " of "
+                  (group (one-or-more (or word punct (syntax symbol))))
+                  eol))))
+
+    (add-to-list 'compilation-error-regexp-alist
+                 (list scss-error-regexp 2 1 nil 2 2))))
+
+(define-key css-mode-map (kbd "C-c m") #'css-mode-hydra/body)
+
+;; Align CSS files like so:
+
+;;   body        { color: #ffffff;            }
+;;   .some-class { background-color: #ffffff; }
+;;   #some-id    { width: 200px;              }
+
+;;   .some-more-class {
+;;       color:            #ffffff;
+;;       background-color: #ffffff;
+;;       width:            200px;
+;;   }
+
+;; Keep these in order. They are each added to the _front_ of the
+;; list and are applied in order. Changing their order will change
+;; the results.
+(add-to-list 'align-rules-list
+             `(css-closing-brace
+               (regexp . ,(rx (group (0+ whitespace)) "}" eol))
+               (group . (1))
+               (modes . '(scss-mode css-mode))))
+
+(add-to-list 'align-rules-list
+             `(css-colons
+               (regexp . ,(rx bol
+                              (0+ whitespace)
+                              (1+ (any (?a . ?z) ?- ?$))
+                              ":"
+                              (group (0+ whitespace))
+                              (0+ nonl)
+                              ";"
+                              eol))
+               (group . (1))
+               (modes . '(scss-mode css-mode))
+               (repeat . t)))
+
+(add-to-list 'align-rules-list
+             `(css-opening-brace
+               (regexp . ,(rx bol
+                              (0+ whitespace)
+                              (0+ (any ?# ?. ?, ?\s ?& ?: ?-
+                                       (?a . ?z) (?A . ?Z) (?0 . ?9)))
+                              (any (?a . ?z) (?A . ?Z) (?0 . ?9))
+                              (group (0+ whitespace))
+                              "{"
+                              (0+ nonl)))
+               (group . (1))
+               (modes . '(scss-mode css-mode))))
+
+(provide 'oni-css)
+;;; oni-css.el ends here