[IMP] digest: colors following company colors

Changes the background color of the digest to follow the
company color theme the same way it has been done for
the email layout.

task-2944770

Part-of: odoo/odoo#101399

addons/digest/data/digest_data.xml

@@ -12,13 +12,16 @@
         <meta http-equiv="X-UA-Compatible" content="IE=9; IE=8; IE=7; IE=EDGE" />
 
         <style type="text/css">
+            :root {
+                --color-company: <t t-esc="company.secondary_color or '#875a7b'"/>;
+            }
             body {
                 margin: 0;
                 padding: 0;
                 font-family: Arial, Helvetica, Verdana, sans-serif;
             }
             #header_background {
-                background-color: #875a7b;
+                background-color: var(--color-company);
             }
             .global_layout {
                 max-width: 588px;
@@ -40,7 +43,7 @@
             }
             .button {
                 float: right;
-                background-color: #875a7b;
+                background-color: var(--color-company);
                 color: #ffffff;
                 border-radius: 5px;
             }
@@ -61,7 +64,7 @@
                 text-justify: inter-word;
             }
             .tip_button {
-                background-color: #875a7b;
+                background-color: var(--color-company);
                 border-radius: 5px;
                 margin: 14px 16px 14px 0px;
                 padding: 10px;
@@ -97,7 +100,7 @@
                 padding-top: 2px;
             }
             .kpi_cell_center {
-                border-top: 2px solid #875A7B;
+                border-top: 2px solid var(--color-company);
             }
             .kpi_cell_border {
                 border-top: 2px solid #00A09D;
@@ -108,7 +111,7 @@
                 text-decoration: none;
             }
             .kpi_center_col {
-                color: #875A7B;
+                color: var(--color-company);
             }
             .kpi_border_col {
                 color: #00A09D;
@@ -164,7 +167,7 @@
             }
             .odoo_link_text {
                 font-weight: bold;
-                color: #875a7b;
+                color: var(--color-company);
             }
             .run_business {
                 color: #2d2a26;
@@ -260,8 +263,8 @@
                 }
                 #header {
                     padding: 20px 30px 25px 30px;
-                    border-start: 1px solid #875a7b;
-                    border-end: 1px solid #875a7b;
+                    border-start: 1px solid var(--color-company);
+                    border-end: 1px solid var(--color-company);
                 }
                 .global_layout {
                     padding: 25px 30px 30px 30px;