golden hour

/var/www/html/wp-content/plugins/filester/includes/File_manager/lib/themes/windows-10/css

File/Folder	Size	Actions
README.md	2.4 KB
contextmenu.css	1.02 KB
dialog.css	2.38 KB
icons.css	2.2 KB
main.css	643 B
navbar.css	1.76 KB
reset.css	1.52 KB
statusbar.css	545 B
theme.css	640 B
toolbar.css	8.06 KB
view-list.css	2.33 KB
view-thumbnail.css	1.03 KB

Edit: view-thumbnail.css

/* view-thumbnail.css */
/* Wrapper for thumbnail view */
.elfinder .elfinder-cwd-view-icons {
}

/* File wrapper */
.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file {
  width: 80px;
  height: 80px;
  border: 1px solid transparent;
  border-radius: 0;
}

/* Hovered file */
.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file.ui-state-hover {
  background: #e5f3ff;
}

/* Selected file */
.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file.ui-selected {
  background: #cce8ff;
  border: 1px solid #99d1ff;
}

/* File icon */
.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file .elfinder-cwd-icon {
}

.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file .elfinder-cwd-icon-directory,
.elfinder .elfinder-dialog .elfinder-cwd-icon-directory {
  background-color: transparent;
  background-image: url('../images/48px/directory.png') !important;
  background-position: center center;
  height: 48px;
  width: 48px;
}

/* File name */
.elfinder .elfinder-cwd-view-icons .elfinder-cwd-file .elfinder-cwd-filename {
  color: #000 !important;
}