diff --git a/Sources/Actions/Profile/Main.php b/Sources/Actions/Profile/Main.php
index dcebc03b17..a83fbd3cdb 100644
--- a/Sources/Actions/Profile/Main.php
+++ b/Sources/Actions/Profile/Main.php
@@ -675,6 +675,7 @@ public function execute(): void
 
 		Utils::$context['template_layers'][] = 'profile';
 
+		Theme::loadCSSFile('profile.css', ['minimize' => true, 'order_pos' => 2], 'smf_profile');
 		Theme::loadJavaScriptFile('profile.js', ['defer' => false, 'minimize' => true], 'smf_profile');
 
 		// Right - are we saving - if so let's save the old data first.
diff --git a/Themes/default/css/index.css b/Themes/default/css/index.css
index 1bb917ffce..2f2e70e177 100644
--- a/Themes/default/css/index.css
+++ b/Themes/default/css/index.css
@@ -2489,137 +2489,11 @@ dl {
 	overflow: auto;
 }
 
-/* The basic user info on the left */
-#basicinfo {
-	width: 20%;
-	float: left;
-}
-#detailedinfo {
-	width: 79.5%;
-	float: right;
-}
-#basicinfo > * {
-	margin-bottom: 3px;
-}
-#basicinfo h4 {
-	font-size: 1.4em;
-	font-weight: normal;
-	-webkit-hyphens: auto;
-	-ms-hyphens: auto;
-	hyphens: auto;
-	word-wrap: break-word; /* IE fallback */
-	overflow-wrap: break-word;
-}
-#basicinfo h4 span.position {
-	font-size: 0.8em;
-	display: block;
-}
 #basicinfo img.avatar, dl.settings img.avatar {
 	display: block;
 	max-width: 160px;
 	height: auto !important;
 }
-#basicinfo ul {
-	list-style-type: none;
-}
-#basicinfo .icon_fields li {
-	display: block;
-	float: left;
-	margin-right: 5px;
-	height: 20px;
-}
-#basicinfo #userstatus {
-	display: block;
-	clear: both;
-}
-#basicinfo #userstatus img {
-	vertical-align: middle;
-}
-#detailedinfo dl, #tracking dl {
-	clear: right;
-	overflow: auto;
-	margin: 0 0 18px 0;
-	padding: 0 0 15px 0;
-	border-bottom: 1px #ccc solid;
-}
-#detailedinfo dt, #tracking dt {
-	width: 35%;
-	margin: 0 0 3px 0;
-	font-weight: bold;
-	color: var(--profile-dt-color);
-}
-#detailedinfo dd, #tracking dd {
-	width: 65%;
-	float: left;
-	margin: 0 0 3px 0;
-}
-#detailedinfo dl.settings:last-of-type {
-	border-bottom: 0;
-}
-#detailedinfo dt.clear {
-	width: 100%;
-}
-#personal_picture {
-	display: block;
-	margin-bottom: 4px;
-}
-#avatar_server_stored div {
-	float: left;
-}
-#avatar_upload {
-	overflow: auto;
-}
-#smileypr {
-	margin-left: 10px;
-}
-.edit_avatar_img {
-	margin: 0 0 1em;
-}
-
-/* Activity by time */
-#activitytime {
-	margin: 6px 0;
-}
-.activity_stats {
-	margin: 10px 0;
-}
-.activity_stats li {
-	width: 4.16%;
-	float: left;
-	text-align: center;
-}
-.activity_stats li span {
-	display: block;
-	border: 1px solid var(--activitystats-border-color);
-	border-left: none;
-	border-right: none;
-	background: var(--activitystats-bg);
-}
-.activity_stats li.last span {
-	border-right: none;
-}
-.activity_stats li .generic_bar {
-	height: 100px;
-	border-bottom: none;
-	border-bottom-left-radius: 0;
-	border-bottom-right-radius: 0;
-	margin: 0 auto;
-}
-.activity_stats li .generic_bar span {
-	position: absolute;
-	top: -1000em;
-	left: -1000em;
-}
-
-.profile_pie {
-	background: url(../images/stats_pie.png);
-	background-size: auto 20px;
-	float: left;
-	height: 20px;
-	width: 20px;
-	margin: 0 12px 0 0;
-	text-indent: -1000em;
-}
 
 /* View posts */
 .topic .time {
@@ -2659,10 +2533,6 @@ dl {
 	height: auto !important;
 	height: 80px;
 }
-.topic .mod_icons {
-	text-align: right;
-	margin-right: 12px;
-}
 
 #creator dt {
 	width: 40%;
@@ -2674,10 +2544,6 @@ dl {
 .centericon {
 	vertical-align: middle;
 }
-.sizefix {
-	width: 16px;
-	height: 16px;
-}
 
 /* The board picker's title bar is one element now, the summary of a details.
 /* It carries both bar classes, and .titlebg comes later in this file with a
@@ -2745,41 +2611,6 @@ dl {
 	background: var(--picktheme-selected-bg);
 }
 
-/* Signature preview */
-
-#preview_signature, #preview_signature_display {
-	width: 100%;
-	overflow: hidden;
-}
-
-/* Issue a warning */
-#warn_body {
-	width: 100%;
-	font-size: 0.9em;
-}
-#warn_temp {
-	font-size: smaller;
-}
-
-/* Warning level bar */
-.warning_level {
-	text-align: center;
-	font-weight: bold;
-	max-width: 250px;
-}
-.warning_level.none .bar {
-	background-color: var(--warninglevel-bg_none);
-}
-.warning_level.watched .bar {
-	background-color: var(--warninglevel-bg_watched);
-}
-.warning_level.moderated .bar {
-	background-color: var(--warninglevel-bg_moderated);
-}
-.warning_level.muted .bar {
-	background-color: var(--warninglevel-bg_muted);
-}
-
 /* Styles for the statistics center.
 ------------------------------------------------- */
 #statistics .roundframe {
diff --git a/Themes/default/css/profile.css b/Themes/default/css/profile.css
new file mode 100644
index 0000000000..c54074e9dd
--- /dev/null
+++ b/Themes/default/css/profile.css
@@ -0,0 +1,203 @@
+/* Styles for the profile.
+/*
+/* Loaded by SMF\Actions\Profile\Main only when a profile is being shown, so
+/* nothing here reaches any other page and none of it needs to.
+/*
+/* What lives here is what only the profile draws. Plenty of the profile's
+/* appearance still comes from index.css, because the profile shares it: the
+/* post list it renders is the same one the moderation centre, personal
+/* messages, recent posts and search render, the board picker is shared with
+/* search, and the paid subscription, theme picker and theme settings blocks
+/* belong to the admin centre rather than to a member looking at their own
+/* page. Those stay where every page can see them. */
+
+/* The basic user info on the left */
+#basicinfo {
+	width: 20%;
+	float: left;
+}
+
+#detailedinfo {
+	width: 79.5%;
+	float: right;
+}
+
+#basicinfo > * {
+	margin-bottom: 3px;
+}
+
+#basicinfo h4 {
+	font-size: 1.4em;
+	font-weight: normal;
+	-webkit-hyphens: auto;
+	-ms-hyphens: auto;
+	hyphens: auto;
+	word-wrap: break-word; /* IE fallback */
+	overflow-wrap: break-word;
+}
+
+#basicinfo h4 span.position {
+	font-size: 0.8em;
+	display: block;
+}
+
+#basicinfo ul {
+	list-style-type: none;
+}
+
+#basicinfo .icon_fields li {
+	display: block;
+	float: left;
+	margin-right: 5px;
+	height: 20px;
+}
+
+#basicinfo #userstatus {
+	display: block;
+	clear: both;
+}
+
+#basicinfo #userstatus img {
+	vertical-align: middle;
+}
+
+#detailedinfo dl, #tracking dl {
+	clear: right;
+	overflow: auto;
+	margin: 0 0 18px 0;
+	padding: 0 0 15px 0;
+	border-bottom: 1px #ccc solid;
+}
+
+#detailedinfo dt, #tracking dt {
+	width: 35%;
+	margin: 0 0 3px 0;
+	font-weight: bold;
+	color: var(--profile-dt-color);
+}
+
+#detailedinfo dd, #tracking dd {
+	width: 65%;
+	float: left;
+	margin: 0 0 3px 0;
+}
+
+#detailedinfo dl.settings:last-of-type {
+	border-bottom: 0;
+}
+
+#detailedinfo dt.clear {
+	width: 100%;
+}
+
+#personal_picture {
+	display: block;
+	margin-bottom: 4px;
+}
+
+#avatar_server_stored div {
+	float: left;
+}
+
+#avatar_upload {
+	overflow: auto;
+}
+
+#smileypr {
+	margin-left: 10px;
+}
+
+.edit_avatar_img {
+	margin: 0 0 1em;
+}
+
+/* Activity by time */
+#activitytime {
+	margin: 6px 0;
+}
+
+.activity_stats {
+	margin: 10px 0;
+}
+
+.activity_stats li {
+	width: 4.16%;
+	float: left;
+	text-align: center;
+}
+
+.activity_stats li span {
+	display: block;
+	border: 1px solid var(--activitystats-border-color);
+	border-left: none;
+	border-right: none;
+	background: var(--activitystats-bg);
+}
+
+.activity_stats li.last span {
+	border-right: none;
+}
+
+.activity_stats li .generic_bar {
+	height: 100px;
+	border-bottom: none;
+	border-bottom-left-radius: 0;
+	border-bottom-right-radius: 0;
+	margin: 0 auto;
+}
+
+.activity_stats li .generic_bar span {
+	position: absolute;
+	top: -1000em;
+	left: -1000em;
+}
+
+.profile_pie {
+	background: url(../images/stats_pie.png);
+	background-size: auto 20px;
+	float: left;
+	height: 20px;
+	width: 20px;
+	margin: 0 12px 0 0;
+	text-indent: -1000em;
+}
+
+/* Signature preview */
+
+#preview_signature, #preview_signature_display {
+	width: 100%;
+	overflow: hidden;
+}
+
+/* Issue a warning */
+#warn_body {
+	width: 100%;
+	font-size: 0.9em;
+}
+
+#warn_temp {
+	font-size: smaller;
+}
+
+/* Warning level bar */
+.warning_level {
+	text-align: center;
+	font-weight: bold;
+	max-width: 250px;
+}
+
+.warning_level.none .bar {
+	background-color: var(--warninglevel-bg_none);
+}
+
+.warning_level.watched .bar {
+	background-color: var(--warninglevel-bg_watched);
+}
+
+.warning_level.moderated .bar {
+	background-color: var(--warninglevel-bg_moderated);
+}
+
+.warning_level.muted .bar {
+	background-color: var(--warninglevel-bg_muted);
+}