diff --git a/web/app/controllers/announcements.php b/web/app/controllers/announcements.php
index 66c32c5..68cd74b 100644
--- a/web/app/controllers/announcements.php
+++ b/web/app/controllers/announcements.php
@@ -7,10 +7,7 @@
 		become403Page();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 	
 	function echoBlogCell($blog) {
@@ -45,22 +42,16 @@
 	</tr>
 EOD;
 	$config = [
-		'table_classes' => ['table', 'table-hover'],
-		'page_len' => 40
+		'page_len' => 40,
+		'div_classes' => ['card', 'my-3'],
+		'table_classes' => ['table', 'uoj-table', 'mb-0'],
 	];
-
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$config['div_classes'] = ['card', 'my-3'];
-		$config['table_classes'] = ['table', 'uoj-table', 'mb-0'];
-	}
 	?>
 <?php echoUOJPageHeader(UOJLocale::get('announcements')) ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="row">
 <!-- left col -->
 <div class="col-lg-9">
-<?php endif ?>
 
 <h1 class="h2">
 	<?= UOJLocale::get('announcements') ?>
@@ -68,7 +59,6 @@ EOD;
 
 <?php echoLongTable(array('blogs.id', 'poster', 'title', 'post_time', 'zan', 'level'), 'important_blogs, blogs', 'is_hidden = 0 and important_blogs.blog_id = blogs.id', 'order by level desc, important_blogs.blog_id desc', $header, 'echoBlogCell', $config); ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
 <!-- end left col -->
 
@@ -79,6 +69,5 @@ EOD;
 <!-- end right col -->
 
 </div>
-<?php endif ?>
 
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/blogs.php b/web/app/controllers/blogs.php
index 9509269..33346e6 100644
--- a/web/app/controllers/blogs.php
+++ b/web/app/controllers/blogs.php
@@ -1,4 +1,5 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -8,62 +9,21 @@
 	if (!isNormalUser($myUser) && UOJConfig::$data['switch']['force-login']) {
 		become403Page();
 	}
-
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
-	function echoBlogCell($blog) {
-		global $REQUIRE_LIB;
-
-		echo '<tr>';
-		if ($blog['is_hidden']) {
-			echo '<td><span class="text-danger">[已隐藏]</span> ' . getBlogLink($blog['id']) . '</td>';
-		} else {
-			echo '<td>' . getBlogLink($blog['id']) . '</td>';
-		}
-		echo '<td>' . getUserLink($blog['poster']) . '</td>';
-		echo '<td>' . $blog['post_time'] . '</td>';
-		echo '</tr>';
-	}
-	$header = <<<EOD
-	<tr>
-		<th width="60%">标题</th>
-		<th width="20%">发表者</th>
-		<th width="20%">发表日期</th>
-	</tr>
-EOD;
-	$config = array();
-	$config['table_classes'] = array('table', 'table-hover');
-
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$config['div_classes'] = array('card', 'my-3', 'table-responsive');
-		$config['table_classes'] = array('table', 'uoj-table', 'mb-0');
-	}
 	?>
 <?php echoUOJPageHeader(UOJLocale::get('blogs')) ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="row">
+
+<!-- left col -->
 <div class="col-lg-9">
-<div class="d-flex flex-wrap justify-content-between">
-<?php endif ?>
 
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-<?php if (Auth::check()): ?>
-<div class="float-right">
-	<div class="btn-group">
-		<a href="<?= HTML::blog_url(Auth::id(), '/') ?>" class="btn btn-secondary btn-sm">我的博客首页</a>
-		<a href="<?= HTML::blog_url(Auth::id(), '/post/new/write')?>" class="btn btn-primary btn-sm"><span class="glyphicon glyphicon-edit"></span> 写新博客</a>
-	</div>
-</div>
-<?php endif ?>
-<?php endif ?>
+<!-- title container -->
+<div class="d-flex flex-wrap justify-content-between align-items-center">
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <h1 class="h2">
 	<?= UOJLocale::get("blogs overview") ?>
 </h1>
+
 <div class="text-end">
 	<div class="btn-group">
 		<a href="<?= HTML::blog_url(Auth::id(), '/') ?>" class="btn btn-secondary btn-sm">
@@ -75,24 +35,50 @@ EOD;
 		</a>
 	</div>
 </div>
-<?php else: ?>
-<h3>博客总览</h3>
-<?php endif ?>
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
-<?php endif ?>
+<!-- end title container -->
 
-<?php echoLongTable(array('id', 'poster', 'title', 'post_time', 'zan', 'is_hidden'), 'blogs', isSuperUser($myUser) ? "1" : "is_hidden = 0 or poster = '{$myUser['username']}'", 'order by post_time desc', $header, 'echoBlogCell', $config); ?>
+<?php
+echoLongTable(
+	['id', 'poster', 'title', 'post_time', 'zan', 'is_hidden'],
+	'blogs',
+	isSuperUser($myUser) ? "1" : "is_hidden = 0 or poster = '{$myUser['username']}'",
+	'order by post_time desc',
+	<<<EOD
+	<tr>
+		<th width="60%">标题</th>
+		<th width="20%">发表者</th>
+		<th width="20%">发表日期</th>
+	</tr>
+EOD,
+	function($blog) {
+		echo '<tr>';
+		echo '<td>';
+		echo getBlogLink($blog['id']);
+		if ($blog['is_hidden']) {
+			echo ' <span class="badge text-bg-danger"><i class="bi bi-eye-slash-fill"></i> ', UOJLocale::get('hidden'), '</span> ';
+		}
+		echo '</td>';
+		echo '<td>' . getUserLink($blog['poster']) . '</td>';
+		echo '<td>' . $blog['post_time'] . '</td>';
+		echo '</tr>';
+	},
+	[
+		'page_len' => 10,
+		'div_classes' => ['card', 'my-3', 'table-responsive'],
+		'table_classes' => ['table', 'uoj-table', 'mb-0'],
+	]
+);
+	?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
 
+<!-- right col -->
 <aside class="col-lg-3 mt-3 mt-lg-0">
-<?php uojIncludeView('sidebar', array()) ?>
+<?php uojIncludeView('sidebar') ?>
 </aside>
+<!-- end right col -->
 
 </div>
-<?php endif ?>
 
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/contest_inside.php b/web/app/controllers/contest_inside.php
index c4fa823..a66ea91 100644
--- a/web/app/controllers/contest_inside.php
+++ b/web/app/controllers/contest_inside.php
@@ -1,9 +1,8 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('mathjax');
 	requirePHPLib('form');
 
-	$REQUIRE_LIB['bootstrap5'] = '';
-	$REQUIRE_LIB['mathjax'] = '';
-
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
 		redirectToLogin();
 	}
@@ -354,7 +353,7 @@ EOD;
 	}
 	
 	function echoDashboard() {
-		global $contest, $post_notice, $post_question, $reply_question, $REQUIRE_LIB;
+		global $contest, $post_notice, $post_question, $reply_question;
 		
 		$myname = Auth::id();
 		$contest_problems = DB::selectAll("select contests_problems.problem_id, best_ac_submissions.submission_id from contests_problems left join best_ac_submissions on contests_problems.problem_id = best_ac_submissions.problem_id and submitter = '{$myname}' where contest_id = {$contest['id']} order by contests_problems.dfn, contests_problems.problem_id");
@@ -389,7 +388,6 @@ EOD;
 			'post_question' => $post_question,
 			'my_questions_pag' => $my_questions_pag,
 			'others_questions_pag' => $others_questions_pag,
-			'REQUIRE_LIB' => $REQUIRE_LIB,
 		]);
 	}
 	
diff --git a/web/app/controllers/contest_members.php b/web/app/controllers/contest_members.php
index 031a910..e8d4e09 100644
--- a/web/app/controllers/contest_members.php
+++ b/web/app/controllers/contest_members.php
@@ -1,4 +1,5 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -13,10 +14,6 @@
 		become404Page();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
 	genMoreContestInfo($contest);
 
 	if (isSuperUser($myUser)) {
@@ -178,26 +175,24 @@
 	?>
 <?php echoUOJPageHeader(HTML::stripTags($contest['name']) . ' - ' . UOJLocale::get('contests::contest registrants')) ?>
 
-<h1 class="h2 text-center"><?= $contest['name'] ?></h1>
+<h1 class="h2 text-center">
+	<?= $contest['name'] ?>
+</h1>
+
 <?php if ($contest['cur_progress'] == CONTEST_NOT_STARTED): ?>
 	<?php if ($iHasRegistered): ?>
 		<div class="row">
 			<div class="col-6">
 				<a style="color:green">已报名</a>
 			</div>
-			<div class="col-6
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-		text-end
-	<?php else: ?>
-		text-right
-	<?php endif ?>">
+			<div class="col-6 text-end">
 				<?php $unregister_form->printHTML(); ?>
 			</div>
 		</div>
 	<?php else: ?>
-		<div>当前尚未报名，您可以<a style="color:red" href="/contest/<?= $contest['id'] ?>/register">报名</a>。</div>
+		<div>当前尚未报名，您可以 <a class="text-decoration-none text-danger" href="/contest/<?= $contest['id'] ?>/register">报名</a>。</div>
 	<?php endif ?>
-<div class="top-buffer-sm"></div>
+<div class="mt-2"></div>
 <?php endif ?>
 
 <?php
@@ -220,63 +215,56 @@
 	}
 	$header_row .= '</tr>';
 
-	$config = array('page_len' => 100,
-		'get_row_index' => '',
-		'print_after_table' => function() {
-			global $add_new_contestant_form,
-			$add_group_to_contest_form,
-			$remove_user_from_contest_form,
-			$force_set_user_participated_form;
-
-			if (isset($add_new_contestant_form)) {
-				$add_new_contestant_form->printHTML();
-			}
-			if (isset($add_group_to_contest_form)) {
-				$add_group_to_contest_form->printHTML();
-			}
-			if (isset($remove_user_from_contest_form)) {
-				$remove_user_from_contest_form->printHTML();
-			}
-			if (isset($force_set_user_participated_form)) {
-				$force_set_user_participated_form->printHTML();
-			}
-		}
-	);
-
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$config['div_classes'] = array('card', 'mb-3');
-		$config['table_classes'] = array('table', 'uoj-table', 'mb-0', 'text-center');
-	}
-	
-	echoLongTable(array('*'), 'contests_registrants', "contest_id = {$contest['id']}", 'order by username desc',
+	echoLongTable(
+		['*'],
+		'contests_registrants',
+		"contest_id = {$contest['id']}",
+		'order by username desc',
 		$header_row,
-		function($contest, $num) {
-			global $myUser;
-			global $has_contest_permission, $show_ip, $ip_owner, $has_participated;
-			
-			$user = queryUser($contest['username']);
-			$user_link = getUserLink($contest['username']);
+		function($contestant, $num) use ($myUser, $has_contest_permission, $show_ip, $ip_owner, $has_participated) {
+			$user = queryUser($contestant['username']);
+
 			if (!$show_ip) {
 				echo '<tr>';
 			} else {
 				if ($ip_owner[$user['remote_addr']] != $user['username'] || $forwarded_ip_owner[$user['http_x_forwarded_for']] != $user['username']) {
-					echo '<tr class="danger">';
+					echo '<tr class="table-danger">';
 				} else {
 					echo '<tr>';
 				}
 			}
 			echo '<td>'.$num.'</td>';
-			echo '<td>'.$user_link.'</td>';
+			echo '<td>'.getUserLink($contestant['username']).'</td>';
 			if ($show_ip) {
 				echo '<td>'.$user['remote_addr'].'</td>';
 				echo '<td>'.$user['http_x_forwarded_for'].'</td>';
 			}
 			if ($has_contest_permission) {
-				echo '<td>'.($has_participated[$user['username']] ? 'Yes' : 'No').'</td>';
+				echo '<td>'.($contestant['has_participated'] ? 'Yes' : 'No').'</td>';
 			}
 			echo '</tr>';
 		},
-		$config
+		[
+			'page_len' => 50,
+			'get_row_index' => '',
+			'div_classes' => ['table-responsive', 'card', 'mb-3'],
+			'table_classes' => ['table', 'uoj-table', 'mb-0', 'text-center'],
+		]
 	);
 	?>
+
+<?php
+	if (isset($add_new_contestant_form)) {
+		$add_new_contestant_form->printHTML();
+	}
+	if (isset($add_group_to_contest_form)) {
+		$add_group_to_contest_form->printHTML();
+	}
+	if (isset($remove_user_from_contest_form)) {
+		$remove_user_from_contest_form->printHTML();
+	}
+	if (isset($force_set_user_participated_form)) {
+		$force_set_user_participated_form->printHTML();
+	}
+	?>
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/contests.php b/web/app/controllers/contests.php
index 94397d3..cd80ef5 100644
--- a/web/app/controllers/contests.php
+++ b/web/app/controllers/contests.php
@@ -1,28 +1,19 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
 		redirectToLogin();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
 	$upcoming_contest_name = null;
 	$upcoming_contest_href = null;
 	$rest_second = 1000000;
 	function echoContest($contest) {
-		global $myUser, $upcoming_contest_name, $upcoming_contest_href, $rest_second, $REQUIRE_LIB;
+		global $myUser, $upcoming_contest_name, $upcoming_contest_href, $rest_second;
 
-		$a_class = ' ';
-
-		if (isset($REQUIRE_LIB['bootstrap5'])) {
-			$a_class = ' class="text-decoration-none" ';
-		}
-		
 		$contest_name_link = <<<EOD
-<a $a_class href="/contest/{$contest['id']}">{$contest['name']}</a>
+<a class="text-decoration-none" href="/contest/{$contest['id']}">{$contest['name']}</a>
 EOD;
 		genMoreContestInfo($contest);
 		if ($contest['cur_progress'] == CONTEST_NOT_STARTED) {
@@ -33,18 +24,18 @@ EOD;
 				$rest_second = $cur_rest_second;
 			}
 			if ($myUser != null && hasRegistered($myUser, $contest)) {
-				$contest_name_link .= '<sup><a '.$a_class.' style="color:green">'.UOJLocale::get('contests::registered').'</a></sup>';
+				$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:green">'.UOJLocale::get('contests::registered').'</a></sup>';
 			} else {
-				$contest_name_link .= '<sup><a '.$a_class.' style="color:red" href="/contest/'.$contest['id'].'/register">'.UOJLocale::get('contests::register').'</a></sup>';
+				$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:red" href="/contest/'.$contest['id'].'/register">'.UOJLocale::get('contests::register').'</a></sup>';
 			}
 		} elseif ($contest['cur_progress'] == CONTEST_IN_PROGRESS) {
-			$contest_name_link .= '<sup><a '.$a_class.' style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::in progress').'</a></sup>';
+			$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::in progress').'</a></sup>';
 		} elseif ($contest['cur_progress'] == CONTEST_PENDING_FINAL_TEST) {
-			$contest_name_link .= '<sup><a '.$a_class.' style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::pending final test').'</a></sup>';
+			$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::pending final test').'</a></sup>';
 		} elseif ($contest['cur_progress'] == CONTEST_TESTING) {
-			$contest_name_link .= '<sup><a '.$a_class.' style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::final testing').'</a></sup>';
+			$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:blue" href="/contest/'.$contest['id'].'">'.UOJLocale::get('contests::final testing').'</a></sup>';
 		} elseif ($contest['cur_progress'] == CONTEST_FINISHED) {
-			$contest_name_link .= '<sup><a '.$a_class.'style="color:grey" href="/contest/'.$contest['id'].'/standings">'.UOJLocale::get('contests::ended').'</a></sup>';
+			$contest_name_link .= '<sup><a class="text-decoration-none"  style="color:grey" href="/contest/'.$contest['id'].'/standings">'.UOJLocale::get('contests::ended').'</a></sup>';
 		}
 		
 		$last_hour = round($contest['last_min'] / 60, 2);
@@ -52,44 +43,33 @@ EOD;
 		$click_zan_block = getClickZanBlock('C', $contest['id'], $contest['zan']);
 		echo '<tr>';
 		echo '<td>', $contest_name_link, '</td>';
-		echo '<td>', '<a'.$a_class.'href="'.HTML::timeanddate_url($contest['start_time'], array('duration' => $contest['last_min'])).'">'.$contest['start_time_str'].'</a>', '</td>';
+		echo '<td>', '<a class="text-decoration-none"  href="'.HTML::timeanddate_url($contest['start_time'], array('duration' => $contest['last_min'])).'">'.$contest['start_time_str'].'</a>', '</td>';
 		echo '<td>', UOJLocale::get('hours', $last_hour), '</td>';
-		echo '<td>', '<a'.$a_class.'href="/contest/'.$contest['id'].'/registrants">';
-		
-		if (isset($REQUIRE_LIB['bootstrap5'])) {
-			echo '<i class="bi bi-person-fill"></i>';
-		} else {
-			echo '<span class="glyphicon glyphicon-user"></span>';
-		}
-
-		echo ' &times;'.$contest['player_num'].'</a>', '</td>';
+		echo '<td>', '<a class="text-decoration-none"  href="/contest/'.$contest['id'].'/registrants">', '<i class="bi bi-person-fill"></i>', ' &times;'.$contest['player_num'].'</a>', '</td>';
 		echo '<td>', '<div class="text-left">'.$click_zan_block.'</div>', '</td>';
 		echo '</tr>';
 	}
 	?>
 <?php echoUOJPageHeader(UOJLocale::get('contests')) ?>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
+
+<!-- title container -->
 <div class="d-flex justify-content-between">
-<?php endif ?>
 <h1 class="h2">
 	<?= UOJLocale::get('contests') ?>
 </h1>
-<?php
-if (isSuperUser($myUser)) {
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		echo '<div class="text-end">';
-	} else {
-		echo '<div class="text-right">';
-	}
-	echo '<a href="/contest/new" class="btn btn-primary">'.UOJLocale::get('contests::add new contest').'</a>';
-	echo '</div>';
-}
-	?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
+<?php if (isSuperUser($myUser)): ?>
+<div class="text-end">
+	<a href="/contest/new" class="btn btn-primary"><?= UOJLocale::get('contests::add new contest') ?></a>
 </div>
 <?php endif ?>
-<h4><?= UOJLocale::get('contests::current or upcoming contests') ?></h4>
+
+</div>
+<!-- end title container -->
+
+<h2 class="h4">
+	<?= UOJLocale::get('contests::current or upcoming contests') ?>
+</h2>
 <?php
 			$table_header = '';
 	$table_header .= '<tr>';
@@ -100,12 +80,18 @@ if (isSuperUser($myUser)) {
 	$table_header .= '<th style="width:180px;">'.UOJLocale::get('appraisal').'</th>';
 	$table_header .= '</tr>';
 
-	$table_config = array('page_len' => 40);
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$table_config['div_classes'] = array('card', 'mb-3');
-		$table_config['table_classes'] = array('table', 'uoj-table', 'mb-0', 'text-center');
-	}
-	echoLongTable(array('*'), 'contests', "status != 'finished'", 'order by start_time asc, id asc', $table_header,
+	$table_config = [
+		'page_len' => 40,
+		'div_classes' => ['card', 'mb-3'],
+		'table_classes' => ['table', 'uoj-table', 'mb-0', 'text-center'],
+	];
+
+	echoLongTable(
+		['*'],
+		'contests',
+		"status != 'finished'",
+		'order by start_time asc, id asc',
+		$table_header,
 		echoContest,
 		$table_config
 	);
@@ -128,9 +114,16 @@ EOD;
 	}
 	?>
 
-<h4><?= UOJLocale::get('contests::ended contests') ?></h4>
+<h2 class="h4">
+	<?= UOJLocale::get('contests::ended contests') ?>
+</h2>
 <?php
-	echoLongTable(array('*'), 'contests', "status = 'finished'", 'order by start_time desc, id desc', $table_header,
+	echoLongTable(
+		['*'],
+		'contests',
+		"status = 'finished'",
+		'order by start_time desc, id desc',
+		$table_header,
 		echoContest,
 		$table_config
 	);
diff --git a/web/app/controllers/index.php b/web/app/controllers/index.php
index 393ff68..160b014 100644
--- a/web/app/controllers/index.php
+++ b/web/app/controllers/index.php
@@ -3,28 +3,20 @@
 	$countdowns = DB::selectAll("select * from countdowns order by end_time asc");
 	$friend_links = DB::selectAll("select * from friend_links order by level desc, id asc");
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
+	requireLib('bootstrap5');
 	?>
 <?php echoUOJPageHeader(UOJConfig::$data['profile']['oj-name-short']) ?>
 <div class="row">
 	<div class="col-lg-9">
 		<div class="card card-default">
 			<div class="card-body">
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-					<h4 class="card-title">
-						<?= UOJLocale::get('announcements') ?>
-					</h4>
-				<?php endif ?>
+				<h4 class="card-title">
+					<?= UOJLocale::get('announcements') ?>
+				</h4>
 				<table class="table table-sm">
 					<thead>
 						<tr>
-							<th style="width:60%">
-								<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-									<?= UOJLocale::get('announcements') ?>
-								<?php endif ?>
-							</th>
+							<th style="width:60%"></th>
 							<th style="width:20%"></th>
 							<th style="width:20%"></th>
 						</tr>
@@ -41,11 +33,7 @@
 							?>
 							<tr>
 								<td>
-									<a href="/blogs/<?= $blog['id'] ?>"
-										<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-										class="text-decoration-none"
-										<?php endif ?>
-										><?= $blog['title'] ?></a>
+									<a href="/blogs/<?= $blog['id'] ?>" class="text-decoration-none"><?= $blog['title'] ?></a>
 									<?= $new_tag ?>
 								</td>
 								<td>by <?= getUserLink($blog['poster']) ?></td>
@@ -55,51 +43,33 @@
 						<?php for ($i = $now_cnt + 1; $i <= 5; $i++): ?>
 							<tr><td colspan="233">&nbsp;</td></tr>
 						<?php endfor ?>
-						<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-							<tr><td class="text-right" colspan="233"><a href="/announcements"><?= UOJLocale::get('all the announcements') ?></a></td></tr>
-						<?php endif ?>
 					</tbody>
 				</table>
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-					<div class="text-end">
-						<a class="text-decoration-none" href="/announcements"><?= UOJLocale::get('all the announcements') ?></a>
-					</div>
-				<?php endif ?>
+				<div class="text-end">
+					<a class="text-decoration-none" href="/announcements">
+						<?= UOJLocale::get('all the announcements') ?>
+					</a>
+				</div>
 			</div>
 		</div>
 		<?php if (!UOJConfig::$data['switch']['force-login'] || Auth::check()): ?>
 			<?php if (!UOJConfig::$data['switch']['force-login'] || isNormalUser($myUser)): ?>
 			
-			<div class="mt-4
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				card
-				<?php endif ?>
-				">
-				
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
+			<div class="mt-4 card">
 				<div class="card-body">
 					<h4 class="card-title"><?= UOJLocale::get('top solver') ?></h4>
-				<?php else: ?>
-					<h3><?= UOJLocale::get('top solver') ?></h3>
-				<?php endif ?>
-					<?php echoRanklist(array(
+					<?php echoRanklist([
 						'echo_full' => true,
 						'top10' => true,
 						'by_accepted' => true,
-						'table_classes' => isset($REQUIRE_LIB['bootstrap5'])
-							? array('table', 'text-center')
-							: array('table', 'table-bordered', 'table-hover', 'table-striped', 'table-text-center'),
-					)) ?>
+						'table_classes' => ['table', 'text-center'],
+					]) ?>
 					<div class="text-center">
-						<a href="/solverlist"
-							<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-							class="text-decoration-none"
-							<?php endif ?>
-							><?= UOJLocale::get('view all') ?></a>
+						<a href="/solverlist" class="text-decoration-none">
+							<?= UOJLocale::get('view all') ?>
+						</a>
 					</div>
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 				</div>
-				<?php endif ?>
 			</div>
 			<?php endif ?>
 		<?php else: ?>
@@ -115,23 +85,11 @@
 			<img class="media-object img-thumbnail" src="/images/logo.png" alt="Logo" />
 		</div>
 		<div class="card card-default mb-2">
-			<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 			<div class="card-header bg-white">
 				<b><?= UOJLocale::get('countdowns') ?></b>
 			</div>
-			<?php endif ?>
 			<div class="card-body">
-				<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-					<h4 class="card-title" style="font-size: 1.25rem">
-						<?= UOJLocale::get('countdowns') ?>
-					</h4>
-				<?php endif ?>
-				<ul class="
-					<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-						list-unstyled
-					<?php else: ?>
-						pl-4
-					<?php endif ?> mb-0">
+				<ul class="list-unstyled mb-0">
 					<?php foreach ($countdowns as $countdown): ?>
 						<?php
 							$enddate = strtotime($countdown['end_time']);
@@ -156,37 +114,20 @@
 		</div>
 
 		<?php if (Auth::check()): ?>
-			<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				<?php uojIncludeView('sidebar', ['assignments_hidden' => '', 'groups_hidden' => '']) ?>
-			<?php endif ?>
+			<?php uojIncludeView('sidebar', ['assignments_hidden' => '', 'groups_hidden' => '']) ?>
 		<?php endif ?>
 
 		<div class="card card-default mb-2">
-			<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				<div class="card-header bg-white">
-					<b><?= UOJLocale::get('friend links') ?></b>
-				</div>
-			<?php endif ?>
+			<div class="card-header bg-white">
+				<b><?= UOJLocale::get('friend links') ?></b>
+			</div>
 			<div class="card-body">
-				<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-				<h4 class="card-title" style="font-size: 1.25rem">
-					<?= UOJLocale::get('friend links') ?>
-				</h4>
-				<?php endif ?>
-				<ul class="
-					<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-						ps-3
-					<?php else: ?>
-						pl-4
-					<?php endif ?>
-					mb-0">
+				<ul class="ps-3 mb-0">
 					<?php foreach ($friend_links as $friend_link): ?>
 						<li>
-							<a
-							<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-							class="text-decoration-none"
-							<?php endif ?>
-							href="<?= $friend_link['url'] ?>" target="_blank"><?= $friend_link['title'] ?></a>
+							<a class="text-decoration-none"	href="<?= $friend_link['url'] ?>" target="_blank">
+								<?= $friend_link['title'] ?>
+							</a>
 						</li>
 					<?php endforeach ?>
 				</ul>
diff --git a/web/app/controllers/login.php b/web/app/controllers/login.php
index da3e244..24cf370 100644
--- a/web/app/controllers/login.php
+++ b/web/app/controllers/login.php
@@ -1,6 +1,9 @@
 <?php
 	use Gregwar\Captcha\PhraseBuilder;
 	use Gregwar\Captcha\CaptchaBuilder;
+	
+	requireLib('md5');
+	requireLib('bootstrap5');
 
 	if (Auth::check()) {
 		redirectTo('/');
@@ -50,10 +53,6 @@
 		die();
 	}
 	?>
-<?php
-	$REQUIRE_LIB['bootstrap5'] = '';
-	$REQUIRE_LIB['md5'] = '';
-	?>
 <?php echoUOJPageHeader(UOJLocale::get('login')) ?>
 
 <style>
diff --git a/web/app/controllers/problem.php b/web/app/controllers/problem.php
index 8765489..98939f4 100644
--- a/web/app/controllers/problem.php
+++ b/web/app/controllers/problem.php
@@ -1,4 +1,7 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('hljs');
+	requireLib('mathjax');
 	requirePHPLib('form');
 	requirePHPLib('judger');	
 
@@ -9,10 +12,6 @@
 	if (!validateUInt($_GET['id']) || !($problem = queryProblemBrief($_GET['id']))) {
 		become404Page();
 	}
-	
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
 
 	$problem_content = queryProblemContent($problem['id']);
 	
@@ -220,16 +219,6 @@ EOD
 	}
 	?>
 
-<?php
-	requireLib('mathjax');
-
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		requireLib('hljs');
-	} else {
-		$REQUIRE_LIB['shjs'] = '';
-	}
-	?>
-
 <?php echoUOJPageHeader(HTML::stripTags($problem['title']) . ' - ' . UOJLocale::get('problems::problem')) ?>
 <?php
 	$limit = getUOJConf("/var/uoj_data/{$problem['id']}/problem.conf");
@@ -239,14 +228,12 @@ EOD
 	$problem_uploader = $problem['uploader'];
 	?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="row">
 
 <!-- Left col -->
 <div class="col-lg-9">
-<?php endif ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5']) && $contest): ?>
+<?php if ($contest): ?>
 <!-- 比赛导航 -->
 <?php
 	$tabs_info = array(
@@ -287,65 +274,17 @@ EOD
 	</div>
 <?php endif ?>
 
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-<div class="row d-flex justify-content-center">
-	<span class="badge badge-secondary mr-1">时间限制:<?=$time_limit!=null?"$time_limit s":"N/A"?></span>
-	<span class="badge badge-secondary mr-1">空间限制:<?=$memory_limit!=null?"$memory_limit MB":"N/A"?></span>
-	<span class="badge badge-secondary mr-1">上传者:<?= $problem_uploader ?: "root" ?></span>
-</div>
-<div class="float-right">
-	<?= getClickZanBlock('P', $problem['id'], $problem['zan']) ?>
-</div>
-<?php endif ?>
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="card card-default mb-2">
 <div class="card-body">
-<?php endif ?>
 
+<h1 class="h2 card-title text-center">
 <?php if ($contest): ?>
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-<h1 class="h2 card-title text-center">
 	<?= $problem_letter ?>. <?= $problem['title'] ?>
-</h1>
 <?php else: ?>
-<div class="page-header row">
-	<h1 class="col-md-3 text-left"><small><?= $contest['name'] ?></small></h1>
-	<h1 class="col-md-7 text-center"><?= $problem_letter ?>. <?= $problem['title'] ?></h1>
-	<div class="col-md-2 text-right" id="contest-countdown"></div>
-</div>
-<div class="btn-group float-right" role="group">
-<a role="button" class="btn btn-primary" href="<?= HTML::url("/download.php?type=attachment&id={$problem['id']}") ?>"><span class="glyphicon glyphicon-download-alt"></span> 附件下载</a>
-<a role="button" class="btn btn-info" href="/contest/<?= $contest['id'] ?>/problem/<?= $problem['id'] ?>/statistics"><span class="glyphicon glyphicon-stats"></span> <?= UOJLocale::get('problems::statistics') ?></a>
-</div>
-<?php if ($contest['cur_progress'] <= CONTEST_IN_PROGRESS): ?>
-<script type="text/javascript">
-$('#contest-countdown').countdown(<?= $contest['end_time']->getTimestamp() - UOJTime::$time_now->getTimestamp() ?>);
-</script>
-<?php endif ?>
-<?php endif ?>
-
-<?php else: ?>
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-<h1 class="h2 card-title text-center">
-<?php else: ?>
-<h1 class="page-header text-center">
-<?php endif ?>
 	#<?= $problem['id']?>. <?= $problem['title'] ?>
+<?php endif ?>
 </h1>
 
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-<div class="btn-group float-right" role="group">
-<a role="button" class="btn btn-primary" href="<?= HTML::url("/download.php?type=problem&id={$problem['id']}") ?>"><span class="glyphicon glyphicon-tasks"></span> 测试数据</a>
-<a role="button" class="btn btn-primary" href="<?= HTML::url("/download.php?type=attachment&id={$problem['id']}") ?>"><span class="glyphicon glyphicon-download-alt"></span> 附件下载</a>
-<a role="button" class="btn btn-info" href="/problem/<?= $problem['id'] ?>/statistics"><span class="glyphicon glyphicon-stats"></span> <?= UOJLocale::get('problems::statistics') ?></a>
-</div>
-<?php endif ?>
-<?php endif ?>
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="text-center small">
 	时间限制: <?= $time_limit != null ? "$time_limit s" : "N/A" ?>
 	&emsp;
@@ -355,34 +294,12 @@ $('#contest-countdown').countdown(<?= $contest['end_time']->getTimestamp() - UOJ
 </div>
 
 <hr>
-<?php endif ?>
-
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-<ul class="nav nav-tabs" role="tablist">
-	<li class="nav-item"><a class="nav-link active" href="#statement" role="tab" data-toggle="tab"><span class="glyphicon glyphicon-book"></span> <?= UOJLocale::get('problems::statement') ?></a></li>
-	<li class="nav-item"><a class="nav-link" href="#submit" role="tab" data-toggle="tab"><span class="glyphicon glyphicon-upload"></span> <?= UOJLocale::get('problems::submit') ?></a></li>
-	<?php if ($custom_test_requirement): ?>
-	<li class="nav-item"><a class="nav-link" href="#custom-test" role="tab" data-toggle="tab"><span class="glyphicon glyphicon-console"></span> <?= UOJLocale::get('problems::custom test') ?></a></li>
-	<?php endif ?>
-	<?php if (!$contest || $contest['cur_progress'] >= CONTEST_FINISHED): ?>
-	<li class="nav-item"><a class="nav-link" href="/problem/<?= $problem['id'] ?>/solutions" role="tab"><?= UOJLocale::get('problems::solutions') ?></a></li>
-	<?php endif ?>
-	<?php if (hasProblemPermission($myUser, $problem)): ?>
-	<li class="nav-item"><a class="nav-link" href="/problem/<?= $problem['id'] ?>/manage/statement" role="tab"><?= UOJLocale::get('problems::manage') ?></a></li>
-	<?php endif ?>
-	<?php if ($contest): ?>
-	<li class="nav-item"><a class="nav-link" href="/contest/<?= $contest['id'] ?>" role="tab"><?= UOJLocale::get('contests::back to the contest') ?></a></li>
-	<?php endif ?>
-</ul>
-<?php endif ?>
-
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-<link rel="stylesheet" type="text/css" href="<?= HTML::url('/css/markdown.css') ?>">
-<?php endif ?>
 
 <div class="tab-content">
 	<div class="tab-pane active" id="statement">
-		<article class="mt-3 markdown-body"><?= $problem_content['statement'] ?></article>
+		<article class="mt-3 markdown-body">
+			<?= $problem_content['statement'] ?>
+		</article>
 	</div>
 	<div class="tab-pane" id="submit">
 		<div class="top-buffer-sm"></div>
@@ -401,13 +318,9 @@ $('#contest-countdown').countdown(<?= $contest['end_time']->getTimestamp() - UOJ
 	<?php endif ?>
 </div>
 
-
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
 </div>
-<?php endif ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
 <!-- End left col -->
 
@@ -547,7 +460,6 @@ $(document).ready(function() {
 	});
 });
 </script>
-<?php endif ?>
 
 <?php if ($contest && $contest['cur_progress'] <= CONTEST_IN_PROGRESS): ?>
 <script type="text/javascript">
diff --git a/web/app/controllers/problem_managers_manage.php b/web/app/controllers/problem_managers_manage.php
index 74faf81..9d610e2 100644
--- a/web/app/controllers/problem_managers_manage.php
+++ b/web/app/controllers/problem_managers_manage.php
@@ -1,4 +1,5 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -12,10 +13,6 @@
 		become403Page();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
 	$managers_form = newAddDelCmdForm('managers',
 		function($username) {
 			if (!validateUsername($username) || !queryUser($username)) {
@@ -67,25 +64,15 @@
 	?>
 <?php echoUOJPageHeader(HTML::stripTags($problem['title']) . ' - 管理者 - 题目管理') ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="row">
+<!-- left col -->
 <div class="col-lg-9">
-<?php endif ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <h1 class="h2">
-<?php else: ?>
-<h1 class="page-header text-center">
-<?php endif ?>
-	#<?=$problem['id']?>. <?=$problem['title']?> 管理
+	#<?= $problem['id'] ?>. <?= $problem['title'] ?> 管理
 </h1>
 
-<ul class="nav
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	nav-pills my-3
-	<?php else: ?>
-	nav-tabs
-	<?php endif ?>" role="tablist">
+<ul class="nav nav-pills my-3" role="tablist">
 	<li class="nav-item">
 		<a class="nav-link" href="/problem/<?= $problem['id'] ?>/manage/statement" role="tab">
 			题面
@@ -101,25 +88,12 @@
 			数据
 		</a>
 	</li>
-
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-	<li class="nav-item">
-		<a class="nav-link" href="/problem/<?=$problem['id']?>" role="tab">
-			返回
-		</a>
-	</li>
-<?php endif ?>
 </ul>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="card card-default">
 <div class="card-body">
-<?php endif ?>
 
-<table class="table
-<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-table-hover
-<?php endif ?>">
+<table class="table">
 	<thead>
 		<tr>
 			<th>#</th>
@@ -146,12 +120,9 @@ table-hover
 <?php $update_uploader_form->printHTML(); ?>
 <?php endif ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 </div>
 </div>
-<?php endif ?>
 
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <!-- end left col -->
 </div>
 
@@ -192,8 +163,8 @@ table-hover
 
 <?php uojIncludeView('sidebar', array()) ?>
 </aside>
+<!-- end right col -->
 
 </div>
-<?php endif ?>
 
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/problem_solutions.php b/web/app/controllers/problem_solutions.php
index b5e836e..6a55218 100644
--- a/web/app/controllers/problem_solutions.php
+++ b/web/app/controllers/problem_solutions.php
@@ -1,5 +1,7 @@
 <?php
 	requireLib('bootstrap5');
+	requireLib('hljs');
+	requireLib('mathjax');
 	requirePHPLib('form');
 	requirePHPLib('judger');
 
@@ -161,10 +163,6 @@ EOD;
 		}
 	}
 	?>
-<?php
-	$REQUIRE_LIB['mathjax'] = '';
-	$REQUIRE_LIB['hljs'] = '';
-	?>
 
 <?php echoUOJPageHeader(UOJLocale::get('problems::solutions') . ' - ' . HTML::stripTags($problem['title'])) ?>
 
diff --git a/web/app/controllers/subdomain/blog/aboutme.php b/web/app/controllers/subdomain/blog/aboutme.php
index ebe3bc1..9308417 100644
--- a/web/app/controllers/subdomain/blog/aboutme.php
+++ b/web/app/controllers/subdomain/blog/aboutme.php
@@ -1,4 +1,6 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('calendar_heatmap');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -8,9 +10,6 @@
 	if (!isNormalUser($myUser) && UOJConfig::$data['switch']['force-login']) {
 		become403Page();
 	}
-
-	$REQUIRE_LIB['bootstrap5'] = '';
-	$REQUIRE_LIB['calendar_heatmap'] = '';
 	?>
 <?php echoUOJPageHeader('关于我') ?>
 
diff --git a/web/app/controllers/subdomain/blog/archive.php b/web/app/controllers/subdomain/blog/archive.php
index 36d3cc2..49de88a 100644
--- a/web/app/controllers/subdomain/blog/archive.php
+++ b/web/app/controllers/subdomain/blog/archive.php
@@ -1,4 +1,7 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('mathjax');
+	requireLib('hljs');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -9,8 +12,6 @@
 		become403Page();
 	}
 
-	$REQUIRE_LIB['bootstrap5'] = '';
-	
 	$blogs_cond = "poster = '".UOJContext::userid()."'";
 	if (!UOJContext::hasBlogPermission()) {
 		$blogs_cond .= " and is_hidden = false";
@@ -34,9 +35,6 @@
 	));
 	
 	$all_tags = DB::selectAll("select distinct tag from blogs_tags where blog_id in (select id from blogs where $blogs_cond)");
-	
-	requireLib('mathjax');
-	requireLib('hljs');
 	?>
 <?php echoUOJPageHeader('日志') ?>
 
diff --git a/web/app/controllers/subdomain/blog/blog.php b/web/app/controllers/subdomain/blog/blog.php
index 63f1da9..14b3f36 100644
--- a/web/app/controllers/subdomain/blog/blog.php
+++ b/web/app/controllers/subdomain/blog/blog.php
@@ -1,4 +1,7 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('mathjax');
+	requireLib('hljs');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -26,10 +29,6 @@
 			}
 		}
 	}
-
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
 	
 	$comment_form = new UOJForm('comment');
 	$comment_form->addVTextArea('comment', '内容', '',
@@ -161,23 +160,11 @@
 		'page_len' => 20
 	));
 	?>
-<?php
-	$REQUIRE_LIB['mathjax'] = '';
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$REQUIRE_LIB['hljs'] = '';
-	} else {
-		$REQUIRE_LIB['shjs'] = '';
-	}
-	?>
 <?php echoUOJPageHeader(HTML::stripTags($blog['title']) . ' - 博客') ?>
 <?php echoBlog($blog, array('show_title_only' => isset($_GET['page']) && $_GET['page'] != 1)) ?>
 <h2>
 	评论
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 	<i class="bi bi-chat-fill"></i>
-	<?php else: ?>
-	<span class="glyphicon glyphicon-comment"></span>
-	<?php endif ?>
 </h2>
 <div class="list-group">
 <?php if ($comments_pag->isEmpty()): ?>
@@ -195,59 +182,26 @@
 		$replies_json = json_encode($replies);
 		?>
 	<div id="comment-<?= $comment['id'] ?>" class="list-group-item">
-		<div class="
-		<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-		d-flex
-		<?php else: ?>
-		media
-		<?php endif ?>
-		">
-			<div class="comtposterbox mr-3
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				flex-shrink-0
-				<?php else: ?>
-				media-left
-				<?php endif ?>">
-				<a href="<?= HTML::url('/user/'.$poster['username']) ?>" class="d-none d-sm-block
-					<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-					text-decoration-none
-					<?php endif ?>">
+		<div class="d-flex">
+			<div class="comtposterbox mr-3 flex-shrink-0">
+				<a href="<?= HTML::url('/user/'.$poster['username']) ?>" class="d-none d-sm-block text-decoration-none">
 					<img class="media-object img-rounded" src="<?= $asrc ?>" alt="avatar" />
 				</a>
 			</div>
-			<div id="comment-body-<?= $comment['id'] ?>" class="comtbox
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				flex-grow-1 ms-3
-				<?php else: ?>
-				media-body
-				<?php endif ?>">
+			<div id="comment-body-<?= $comment['id'] ?>" class="comtbox flex-grow-1 ms-3">
 				<div class="row">
 					<div class="col-sm-6"><?= getUserLink($poster['username']) ?></div>
-					<div class="col-sm-6 
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-				text-end
-				<?php else: ?>
-				text-right
-				<?php endif ?>"><?= getClickZanBlock('BC', $comment['id'], $comment['zan']) ?></div>
+					<div class="col-sm-6 text-end"><?= getClickZanBlock('BC', $comment['id'], $comment['zan']) ?></div>
 				</div>
 				<div class="comtbox1"><?= $comment['content'] ?></div>
-				<ul class="list-inline bot-buffer-no
-					<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-					text-end
-					<?php else: ?>
-					text-right
-					<?php endif ?>">
+				<ul class="list-inline mb-0 text-end">
 					<li>
 						<small class="text-muted">
 							<?= $comment['post_time'] ?>
 						</small>
 					</li>
 					<li>
-						<a class="
-							<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-							text-decoration-none
-							<?php endif ?>"
-							id="reply-to-<?= $comment['id'] ?>" href="#">
+						<a class="text-decoration-none" id="reply-to-<?= $comment['id'] ?>" href="#">
 							回复
 						</a>
 					</li>
diff --git a/web/app/controllers/subdomain/blog/blog_delete.php b/web/app/controllers/subdomain/blog/blog_delete.php
index 5a43d18..c476784 100644
--- a/web/app/controllers/subdomain/blog/blog_delete.php
+++ b/web/app/controllers/subdomain/blog/blog_delete.php
@@ -1,4 +1,5 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -9,8 +10,6 @@
 		become403Page();
 	}
 
-	$REQUIRE_LIB['bootstrap5'] = '';
-	
 	if (!UOJContext::hasBlogPermission()) {
 		become403Page();
 	}
diff --git a/web/app/controllers/subdomain/blog/blog_write.php b/web/app/controllers/subdomain/blog/blog_write.php
index 860af62..095ec48 100644
--- a/web/app/controllers/subdomain/blog/blog_write.php
+++ b/web/app/controllers/subdomain/blog/blog_write.php
@@ -1,4 +1,5 @@
 <?php
+	requireLib('bootstrap5');
 	requirePHPLib('form');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
@@ -17,8 +18,6 @@
 			become404Page();
 		}
 	}
-
-	requireLib('bootstrap5');
 	
 	$blog_editor = new UOJBlogEditor();
 	$blog_editor->name = 'blog';
diff --git a/web/app/controllers/subdomain/blog/index.php b/web/app/controllers/subdomain/blog/index.php
index 86d69dd..15ba95a 100644
--- a/web/app/controllers/subdomain/blog/index.php
+++ b/web/app/controllers/subdomain/blog/index.php
@@ -1,4 +1,8 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('hljs');
+	requireLib('mathjax');
+
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
 		redirectToLogin();
 	}
@@ -7,10 +11,6 @@
 		become403Page();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
 	$blogs_pag = new Paginator(array(
 		'col_names' => array('*'),
 		'table_name' => 'blogs',
@@ -20,24 +20,11 @@
 	));
 
 	$all_tags = DB::selectAll("select distinct tag from blogs_tags where blog_id in (select id from blogs where $blogs_cond)");
-	
-	$REQUIRE_LIB['mathjax'] = '';
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		requireLib('hljs');
-	} else {
-		$REQUIRE_LIB['shjs'] = '';
-	}
 	?>
 <?php echoUOJPageHeader(UOJContext::user()['username'] . '的博客') ?>
 
 <div class="row">
-	<div class="
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	col-lg-9
-	<?php else: ?>
-	col-md-9
-	<?php endif ?>
-	">
+	<div class="col-lg-9">
 		<?php if ($blogs_pag->isEmpty()): ?>
 		<div class="text-muted">此人很懒，什么博客也没留下。</div>
 		<?php else: ?>
@@ -49,39 +36,21 @@
 		<?= $blogs_pag->pagination(); ?>
 		</div>
 	</div>
-	<div class="
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	col-lg-3
-	<?php else: ?>
-	col-md-3
-	<?php endif ?>">
+	<div class="col-lg-3">
 		<img class="media-object img-thumbnail center-block" alt="<?= UOJContext::user()['username'] ?> Avatar" src="<?= HTML::avatar_addr(UOJContext::user(), 512) ?>" />
 		<?php if (UOJContext::hasBlogPermission()): ?>
 		<div class="btn-group d-flex mt-3">
 			<a href="<?= HTML::blog_url(UOJContext::userid(), '/post/new/write') ?>" class="btn btn-primary">
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 				<i class="bi bi-pencil-square"></i>
-				<?php else: ?>
-				<span class="glyphicon glyphicon-edit"></span>
-				<?php endif ?>
 				写新博客
 			</a>
 			<a href="<?= HTML::blog_url(UOJContext::userid(), '/slide/new/write') ?>" class="btn btn-primary">
-				<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 				<i class="bi bi-file-earmark-slides"></i>
-				<?php else: ?>
-				<span class="glyphicon glyphicon-edit"></span>
-				<?php endif ?>
 				写新幻灯片
 			</a>
 		</div>
 		<?php endif ?>
-		<div class="card border-info
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	mt-3
-	<?php else: ?>
-	top-buffer-sm
-	<?php endif ?>">
+		<div class="card border-info mt-3">
 			<div class="card-header bg-info">标签</div>
 			<div class="card-body">
 			<?php if ($all_tags): ?>
diff --git a/web/app/controllers/subdomain/blog/self_reviews.php b/web/app/controllers/subdomain/blog/self_reviews.php
index 6e0580b..1db354a 100644
--- a/web/app/controllers/subdomain/blog/self_reviews.php
+++ b/web/app/controllers/subdomain/blog/self_reviews.php
@@ -7,12 +7,11 @@
 		become403Page();
 	}
 
+	requireLib('bootstrap5');
+	requireLib('mathjax');
 	requirePHPLib('form');
 	
 	$username = UOJContext::userid();
-
-	$REQUIRE_LIB['bootstrap5'] = '';
-	$REQUIRE_LIB['mathjax'] = '';
 	?>
 
 <?php echoUOJPageHeader(UOJLocale::get('contests::contest self reviews')) ?>
diff --git a/web/app/controllers/subdomain/blog/slide_write.php b/web/app/controllers/subdomain/blog/slide_write.php
index 3e20af8..f400e22 100644
--- a/web/app/controllers/subdomain/blog/slide_write.php
+++ b/web/app/controllers/subdomain/blog/slide_write.php
@@ -1,5 +1,6 @@
 <?php
 	requirePHPLib('form');
+	requireLib('bootstrap5');
 
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
 		redirectToLogin();
@@ -17,10 +18,6 @@
 			become404Page();
 		}
 	}
-
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
 	
 	$blog_editor = new UOJBlogEditor();
 	$blog_editor->type = 'slide';
@@ -78,17 +75,8 @@
 	$blog_editor->runAtServer();
 	?>
 <?php echoUOJPageHeader('写幻灯片') ?>
-<div class="
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	text-end
-	<?php else: ?>
-	text-right
-	<?php endif ?>">
-<a class="
-	<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	text-decoration-none
-	<?php endif ?>
-	" href="http://uoj.ac/blog/75">这玩意儿怎么用？</a>
+<div class="text-end">
+<a class="text-decoration-none" href="http://uoj.ac/blog/75">这玩意儿怎么用？</a>
 </div>
 <?php $blog_editor->printHTML() ?>
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/submission.php b/web/app/controllers/submission.php
index 107be7f..c20fb7e 100644
--- a/web/app/controllers/submission.php
+++ b/web/app/controllers/submission.php
@@ -1,4 +1,6 @@
 <?php
+	requireLib('bootstrap5');
+	requireLib('hljs');
 	requirePHPLib('form');
 	requirePHPLib('judger');
 
@@ -10,10 +12,6 @@
 		become404Page();
 	}
 
-	if (!isset($_COOKIE['bootstrap4'])) {
-		$REQUIRE_LIB['bootstrap5'] = '';
-	}
-
 	$submission_result = json_decode($submission['result'], true);
 	
 	$problem = queryProblemBrief($submission['problem_id']);
@@ -139,13 +137,6 @@
 		}
 	}
 	?>
-<?php 
-	if (isset($REQUIRE_LIB['bootstrap5'])) {
-		$REQUIRE_LIB['hljs'] = '';
-	} else {
-		$REQUIRE_LIB['shjs'] = '';
-	}
-	?>
 <script>
 	var problem_id = parseInt('<?= $submission['problem_id'] ?>');
 </script>
@@ -182,47 +173,30 @@
 			<h4 class="card-title"><?= UOJLocale::get('details') ?></h4>
 		</div>
 		
-		<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-		<div class="card-body">
-		<?php endif ?>
-
-			<?php echoJudgementDetails($submission_result['details'], $styler, 'details') ?>
-			<?php if ($should_show_details_to_me): ?>
-				<?php if (isset($submission_result['final_result'])): ?>
-					<hr />
-					<?php echoSubmissionDetails($submission_result['final_result']['details'], 'final_details') ?>
-				<?php endif ?>
-				<?php if ($styler->fade_all_details): ?>
-					<hr />
-					<?php echoSubmissionDetails($submission_result['details'], 'final_details') ?>
-				<?php endif ?>
+		<?php echoJudgementDetails($submission_result['details'], $styler, 'details') ?>
+		<?php if ($should_show_details_to_me): ?>
+			<?php if (isset($submission_result['final_result'])): ?>
+				<hr />
+				<?php echoSubmissionDetails($submission_result['final_result']['details'], 'final_details') ?>
+			<?php endif ?>
+			<?php if ($styler->fade_all_details): ?>
+				<hr />
+				<?php echoSubmissionDetails($submission_result['details'], 'final_details') ?>
 			<?php endif ?>
-		
-		<?php if (!isset($REQUIRE_LIB['bootstrap5'])): ?>
-		</div>
 		<?php endif ?>
 	</div>
 <?php endif ?>
 
 <?php if (isset($rejudge_form)): ?>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	<div class="text-end">
-<?php endif ?>
+<div class="text-end">
 	<?php $rejudge_form->printHTML() ?>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	</div>
-<?php endif ?>
+</div>
 <?php endif ?>
 
 <?php if (isset($delete_form)): ?>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	<div class="text-end">
-<?php endif ?>
-	<div class="top-buffer-sm">
-		<?php $delete_form->printHTML() ?>
-	</div>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
-	</div>
-<?php endif ?>
+<div class="text-end">
+	<?php $delete_form->printHTML() ?>
+</div>
 <?php endif ?>
+
 <?php echoUOJPageFooter() ?>
diff --git a/web/app/controllers/submissions_list.php b/web/app/controllers/submissions_list.php
index c229d4f..1a53f99 100644
--- a/web/app/controllers/submissions_list.php
+++ b/web/app/controllers/submissions_list.php
@@ -103,16 +103,13 @@
 <?php
 	echoSubmissionsList($cond,
 		'order by id desc',
-		array(
+		[
 			'judge_time_hidden' => '',
-			'table_config' => (isset($REQUIRE_LIB['bootstrap5']) 
-				? array(
-					'div_classes' => array('card', 'mb-3', 'table-responsive'),
-					'table_classes' => array('table', 'mb-0', 'uoj-table', 'text-center')
-				)
-				: array()
-			),
-		),
+			'table_config' => [
+				'div_classes' => ['card', 'mb-3', 'table-responsive'],
+				'table_classes' => ['table', 'mb-0', 'uoj-table', 'text-center'],
+			]
+		],
 		$myUser);
 	?>
 
diff --git a/web/app/libs/uoj-form-lib.php b/web/app/libs/uoj-form-lib.php
index e2f31d1..0c07de2 100644
--- a/web/app/libs/uoj-form-lib.php
+++ b/web/app/libs/uoj-form-lib.php
@@ -263,8 +263,7 @@ EOD;
 		}
 		public function addCKEditor($name, $label_text, $default_value, $validator_php, $validator_js) {
 			$default_value = htmlspecialchars($default_value);
-			global $REQUIRE_LIB;
-			$REQUIRE_LIB['ckeditor'] = '';
+			$GLOBALS['REQUIRE_LIB']['ckeditor'] = '';
 			
 			$this->is_big = true;
 			
@@ -279,8 +278,7 @@ EOD;
 		}
 		
 		public function addBlogEditor(UOJBlogEditor $editor) {
-			global $REQUIRE_LIB;
-			$REQUIRE_LIB['blog-editor'] = '';
+			$GLOBALS['REQUIRE_LIB']['blog-editor'] = '';
 			
 			$this->is_big = true;
 			
@@ -325,9 +323,8 @@ EOD
 			};
 		}
 		public function addSlideEditor($name, $label_text, $default_value, $validator_php, $validator_js) {
+			$GLOBALS['REQUIRE_LIB']['slide-editor'] = '';
 			$default_value = htmlspecialchars($default_value);
-			global $REQUIRE_LIB;
-			$REQUIRE_LIB['slide-editor'] = '';
 			
 			$this->is_big = true;
 			
diff --git a/web/app/libs/uoj-html-lib.php b/web/app/libs/uoj-html-lib.php
index 70f5ed4..bdb896f 100644
--- a/web/app/libs/uoj-html-lib.php
+++ b/web/app/libs/uoj-html-lib.php
@@ -62,9 +62,7 @@ function becomeMsgPage($msg, $title = '消息') {
 	if (UOJContext::isAjax()) {
 		die($msg);
 	} else {
-		if (!isset($_COOKIE['bootstrap4'])) {
-			$REQUIRE_LIB['bootstrap5'] = '';
-		}
+		$REQUIRE_LIB['bootstrap5'] = '';
 
 		echoUOJPageHeader($title);
 		echo $msg;
diff --git a/web/app/views/contest-dashboard.php b/web/app/views/contest-dashboard.php
index 3b014c8..5b93d11 100644
--- a/web/app/views/contest-dashboard.php
+++ b/web/app/views/contest-dashboard.php
@@ -1,10 +1,5 @@
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="card card-default table-responsive mb-3">
 	<table class="table uoj-table text-center mb-0">
-<?php else: ?>
-<div class="table-responsive">
-	<table class="table table-bordered table-hover table-striped table-text-center">
-<?php endif ?>
 		<thead>
 			<tr>
 				<th style="width:5em">#</th>
@@ -27,13 +22,8 @@
 </div>
 
 <h3><?= UOJLocale::get('contests::contest notice') ?></h3>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="card card-default table-responsive mb-3">
 	<table class="table uoj-table text-center mb-0">
-<?php else: ?>
-<div class="table-responsive">
-	<table class="table table-bordered table-hover table-vertical-middle table-text-center">
-<?php endif ?>
 		<thead>
 			<tr>
 				<th style="width:10em"><?= UOJLocale::get('title') ?></th>
diff --git a/web/app/views/contest-question-table.php b/web/app/views/contest-question-table.php
index 3fbcc14..926ab3e 100644
--- a/web/app/views/contest-question-table.php
+++ b/web/app/views/contest-question-table.php
@@ -6,7 +6,6 @@ if (!isset($can_reply)) {
 }
 
 ?>
-<?php if (isset($REQUIRE_LIB['bootstrap5'])): ?>
 <div class="table-responsive mb-3
 	<?php if (!isset($no_bs5_card)): ?>
 		card card-default
@@ -15,10 +14,6 @@ if (!isset($can_reply)) {
 	<?php if (!isset($no_bs5_card)): ?>
 	uoj-table
 	<?php endif ?>">
-<?php else: ?>
-<div class="table-responsive">
-	<table class="table table-bordered table-hover table-vertical-middle table-text-center">
-<?php endif ?>
 		<thead>
 			<tr>
 				<th style="width:10em">提问者</th>