diff --git a/CHANGELOG.md b/CHANGELOG.md
index 01ef59abbc..4357de046a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,7 +18,8 @@
 - クライアント: MFM関数構文のサジェストを実装
 - クライアント: 未読の通知のみ表示する機能
 - クライアント: 通知ページで通知の種類によるフィルタ
-- クライアント: ピン留めユーザーの設定項目がない問題を修正
+- クライアント: 新しいダークテーマを追加
+- クライアント: テーマコンパイラに hue と saturate 関数を追加
 - ActivityPub: HTML -> MFMの変換を強化
 - API: i/notifications に unreadOnly オプションを追加
 - API: ap系のエンドポイントをログイン必須化+レートリミット追加
@@ -31,6 +32,8 @@
 - クライアント: ヘッダーのタブが折り返される問題を修正
 - クライアント: ヘッダーにタブが表示されている状態でタイトルをクリックしたときにタブ選択が表示されるのを修正
 - クライアント: ユーザーページのタブが機能していない問題を修正
+- クライアント: ピン留めユーザーの設定項目がない問題を修正
+- API: 管理者およびモデレーターをブロックできてしまう問題を修正
 
 ## 12.91.0 (2021/09/22)
 
diff --git a/src/client/components/signup.vue b/src/client/components/signup.vue
index b420bca5a3..cb25eadf06 100644
--- a/src/client/components/signup.vue
+++ b/src/client/components/signup.vue
@@ -56,7 +56,7 @@
 		</label>
 		<captcha v-if="meta.enableHcaptcha" class="_formBlock captcha" provider="hcaptcha" ref="hcaptcha" v-model="hCaptchaResponse" :sitekey="meta.hcaptchaSiteKey"/>
 		<captcha v-if="meta.enableRecaptcha" class="_formBlock captcha" provider="recaptcha" ref="recaptcha" v-model="reCaptchaResponse" :sitekey="meta.recaptchaSiteKey"/>
-		<MkButton class="_formBlock" type="submit" :disabled="shouldDisableSubmitting" primary data-cy-signup-submit>{{ $ts.start }}</MkButton>
+		<MkButton class="_formBlock" type="submit" :disabled="shouldDisableSubmitting" gradate data-cy-signup-submit>{{ $ts.start }}</MkButton>
 	</template>
 </form>
 </template>
diff --git a/src/client/components/ui/button.vue b/src/client/components/ui/button.vue
index e74c4f550b..5f36be0d76 100644
--- a/src/client/components/ui/button.vue
+++ b/src/client/components/ui/button.vue
@@ -1,6 +1,6 @@
 <template>
 <button v-if="!link" class="bghgjjyj _button"
-	:class="{ inline, primary, danger, rounded, full }"
+	:class="{ inline, primary, gradate, danger, rounded, full }"
 	:type="type"
 	@click="$emit('click', $event)"
 	@mousedown="onMousedown"
@@ -11,7 +11,7 @@
 	</div>
 </button>
 <MkA v-else class="bghgjjyj _button"
-	:class="{ inline, primary, danger, rounded, full }"
+	:class="{ inline, primary, gradate, danger, rounded, full }"
 	:to="to"
 	@mousedown="onMousedown"
 >
@@ -36,6 +36,11 @@ export default defineComponent({
 			required: false,
 			default: false
 		},
+		gradate: {
+			type: Boolean,
+			required: false,
+			default: false
+		},
 		rounded: {
 			type: Boolean,
 			required: false,
@@ -137,8 +142,8 @@ export default defineComponent({
 	padding: 8px 14px;
 	text-align: center;
 	font-weight: normal;
-	font-size: 0.9em;
-	line-height: 24px;
+	font-size: 0.8em;
+	line-height: 22px;
 	box-shadow: none;
 	text-decoration: none;
 	background: var(--buttonBg);
@@ -177,6 +182,20 @@ export default defineComponent({
 		}
 	}
 
+	&.gradate {
+		font-weight: bold;
+		color: var(--fgOnAccent) !important;
+		background: linear-gradient(90deg, var(--buttonGradateA), var(--buttonGradateB));
+
+		&:not(:disabled):hover {
+			background: var(--X8);
+		}
+
+		&:not(:disabled):active {
+			background: var(--X8);
+		}
+	}
+
 	&.danger {
 		color: #ff2a2a;
 
diff --git a/src/client/pages/welcome.entrance.a.vue b/src/client/pages/welcome.entrance.a.vue
index 467a6fb1ad..13f0993793 100644
--- a/src/client/pages/welcome.entrance.a.vue
+++ b/src/client/pages/welcome.entrance.a.vue
@@ -27,7 +27,7 @@
 					<div class="desc" v-html="meta.description || $ts.headlineMisskey"></div>
 				</div>
 				<div class="action">
-					<MkButton @click="signup()" inline primary data-cy-signup style="margin-right: 12px;">{{ $ts.signup }}</MkButton>
+					<MkButton @click="signup()" inline gradate data-cy-signup style="margin-right: 12px;">{{ $ts.signup }}</MkButton>
 					<MkButton @click="signin()" inline data-cy-signin>{{ $ts.login }}</MkButton>
 				</div>
 				<div class="status" v-if="onlineUsersCount && stats">
diff --git a/src/client/pages/welcome.entrance.b.vue b/src/client/pages/welcome.entrance.b.vue
index a5c12f09e2..163fc1e35f 100644
--- a/src/client/pages/welcome.entrance.b.vue
+++ b/src/client/pages/welcome.entrance.b.vue
@@ -12,7 +12,7 @@
 				<div class="desc" v-html="meta.description || $ts.headlineMisskey"></div>
 			</div>
 			<div class="action">
-				<MkButton class="signup" @click="signup()" inline primary>{{ $ts.signup }}</MkButton>
+				<MkButton class="signup" @click="signup()" inline gradate>{{ $ts.signup }}</MkButton>
 				<MkButton class="signin" @click="signin()" inline>{{ $ts.login }}</MkButton>
 			</div>
 			<div class="status" v-if="onlineUsersCount && stats">
diff --git a/src/client/pages/welcome.entrance.c.vue b/src/client/pages/welcome.entrance.c.vue
index 2c8db6e264..bf1c9b1998 100644
--- a/src/client/pages/welcome.entrance.c.vue
+++ b/src/client/pages/welcome.entrance.c.vue
@@ -24,7 +24,7 @@
 						<div class="desc" v-html="meta.description || $ts.headlineMisskey"></div>
 					</div>
 					<div class="action">
-						<MkButton @click="signup()" inline primary>{{ $ts.signup }}</MkButton>
+						<MkButton @click="signup()" inline gradate>{{ $ts.signup }}</MkButton>
 						<MkButton @click="signin()" inline>{{ $ts.login }}</MkButton>
 					</div>
 					<div class="status" v-if="onlineUsersCount && stats">
diff --git a/src/client/scripts/theme.ts b/src/client/scripts/theme.ts
index 10842b8943..e79d54fa6d 100644
--- a/src/client/scripts/theme.ts
+++ b/src/client/scripts/theme.ts
@@ -25,6 +25,7 @@ export const builtinThemes = [
 	require('@client/themes/d-persimmon.json5'),
 	require('@client/themes/d-astro.json5'),
 	require('@client/themes/d-future.json5'),
+	require('@client/themes/d-botanical.json5'),
 	require('@client/themes/d-black.json5'),
 ] as Theme[];
 
@@ -91,6 +92,8 @@ function compile(theme: Theme): Record<string, string> {
 				case 'darken': return color.darken(arg);
 				case 'lighten': return color.lighten(arg);
 				case 'alpha': return color.setAlpha(arg);
+				case 'hue': return color.spin(arg);
+				case 'saturate': return color.saturate(arg);
 			}
 		}
 
diff --git a/src/client/themes/_dark.json5 b/src/client/themes/_dark.json5
index 22f4dc13d4..d8be16f60a 100644
--- a/src/client/themes/_dark.json5
+++ b/src/client/themes/_dark.json5
@@ -57,6 +57,8 @@
 		cwHoverBg: '#707b97',
 		buttonBg: 'rgba(255, 255, 255, 0.05)',
 		buttonHoverBg: 'rgba(255, 255, 255, 0.1)',
+		buttonGradateA: '@accent',
+		buttonGradateB: ':hue<20<@accent',
 		inputBorder: 'rgba(255, 255, 255, 0.1)',
 		inputBorderHover: 'rgba(255, 255, 255, 0.2)',
 		listItemHoverBg: 'rgba(255, 255, 255, 0.03)',
diff --git a/src/client/themes/_light.json5 b/src/client/themes/_light.json5
index 64b92dba8a..251aa36c7a 100644
--- a/src/client/themes/_light.json5
+++ b/src/client/themes/_light.json5
@@ -57,6 +57,8 @@
 		cwHoverBg: '#bbc4ce',
 		buttonBg: 'rgba(0, 0, 0, 0.05)',
 		buttonHoverBg: 'rgba(0, 0, 0, 0.1)',
+		buttonGradateA: '@accent',
+		buttonGradateB: ':hue<20<@accent',
 		inputBorder: 'rgba(0, 0, 0, 0.1)',
 		inputBorderHover: 'rgba(0, 0, 0, 0.2)',
 		listItemHoverBg: 'rgba(0, 0, 0, 0.03)',
diff --git a/src/client/themes/d-astro.json5 b/src/client/themes/d-astro.json5
index 08846dec20..2350e3d46d 100644
--- a/src/client/themes/d-astro.json5
+++ b/src/client/themes/d-astro.json5
@@ -46,6 +46,8 @@
 		navIndicator: '@accent',
 		accentLighten: ':lighten<10<@accent',
 		buttonHoverBg: 'rgba(255, 255, 255, 0.1)',
+		buttonGradateA: '@accent',
+		buttonGradateB: ':hue<-20<@accent',
 		driveFolderBg: ':alpha<0.3<@accent',
 		fgHighlighted: ':lighten<3<@fg',
 		panelHeaderBg: ':lighten<3<@panel',
diff --git a/src/client/themes/d-botanical.json5 b/src/client/themes/d-botanical.json5
new file mode 100644
index 0000000000..f3665e22b2
--- /dev/null
+++ b/src/client/themes/d-botanical.json5
@@ -0,0 +1,26 @@
+{
+	id: '504debaf-4912-6a4c-5059-1db08a76b737',
+
+	name: 'Mi Botanical Dark',
+	author: 'syuilo',
+
+	base: 'dark',
+
+	props: {
+		accent: 'rgb(148, 179, 0)',
+		bg: 'rgb(37, 38, 36)',
+		fg: 'rgb(216, 212, 199)',
+		fgHighlighted: '#fff',
+		divider: 'rgba(255, 255, 255, 0.14)',
+		panel: 'rgb(47, 47, 44)',
+		panelHeaderBg: '@panel',
+		panelHeaderDivider: '@divider',
+		header: ':alpha<0.7<@panel',
+		navBg: '#363636',
+		renote: '@accent',
+		mention: 'rgb(212, 153, 76)',
+		mentionMe: 'rgb(212, 210, 76)',
+		hashtag: 'rgb(76, 212, 180)',
+		link: '@accent',
+	},
+}
diff --git a/src/client/themes/d-future.json5 b/src/client/themes/d-future.json5
index 05ffe87bf0..1882609121 100644
--- a/src/client/themes/d-future.json5
+++ b/src/client/themes/d-future.json5
@@ -21,5 +21,7 @@
 		mentionMe: '@accent',
 		hashtag: '#70c0e8',
 		link: '#e88080',
+		buttonGradateA: '@accent',
+		buttonGradateB: ':saturate<30<:hue<30<@accent',
 	},
 }
diff --git a/src/client/ui/_common_/sidebar.vue b/src/client/ui/_common_/sidebar.vue
index 33aea31c39..d00327b096 100644
--- a/src/client/ui/_common_/sidebar.vue
+++ b/src/client/ui/_common_/sidebar.vue
@@ -372,7 +372,7 @@ export default defineComponent({
 						right: 0;
 						bottom: 0;
 						border-radius: 999px;
-						background: var(--accent);
+						background: linear-gradient(90deg, var(--buttonGradateA), var(--buttonGradateB));
 					}
 					
 					&:hover, &.active {
diff --git a/src/client/ui/default.sidebar.vue b/src/client/ui/default.sidebar.vue
index 745ad2d602..e36febb7fa 100644
--- a/src/client/ui/default.sidebar.vue
+++ b/src/client/ui/default.sidebar.vue
@@ -4,7 +4,7 @@
 		<MkAvatar :user="$i" class="avatar"/><MkAcct class="text" :user="$i"/>
 	</button>
 	<div class="post" @click="post" data-cy-open-post-form>
-		<MkButton class="button" primary full>
+		<MkButton class="button" gradate full rounded>
 			<i class="fas fa-pencil-alt fa-fw"></i><span class="text" v-if="!iconOnly">{{ $ts.note }}</span>
 		</MkButton>
 	</div>
diff --git a/src/server/api/endpoints/blocking/create.ts b/src/server/api/endpoints/blocking/create.ts
index 1bf5cf374b..4deaa39974 100644
--- a/src/server/api/endpoints/blocking/create.ts
+++ b/src/server/api/endpoints/blocking/create.ts
@@ -43,6 +43,12 @@ export const meta = {
 			code: 'ALREADY_BLOCKING',
 			id: '787fed64-acb9-464a-82eb-afbd745b9614'
 		},
+
+		cannotBlockModerator: {
+			message: 'Cannot block a moderator or an admin.',
+			code: 'CANNOT_BLOCK_MODERATOR',
+			id: '8544aaef-89fb-e470-9f6c-385d38b474f5'
+		}
 	},
 
 	res: {
@@ -76,8 +82,12 @@ export default define(meta, async (ps, user) => {
 		throw new ApiError(meta.errors.alreadyBlocking);
 	}
 
-	// Create blocking
-	await create(blocker, blockee);
+	try {
+		await create(blocker, blockee);
+	} catch (e) {
+		if (e.id === 'e42b7890-5e4d-9d9c-d54b-cf4dd30adfb5') throw new ApiError(meta.errors.cannotBlockModerator);
+		throw e;
+	}
 
 	NoteWatchings.delete({
 		userId: blocker.id,
diff --git a/src/services/blocking/create.ts b/src/services/blocking/create.ts
index 76c4bda9dc..defe377514 100644
--- a/src/services/blocking/create.ts
+++ b/src/services/blocking/create.ts
@@ -9,8 +9,13 @@ import { User } from '@/models/entities/user';
 import { Blockings, Users, FollowRequests, Followings, UserListJoinings, UserLists } from '@/models/index';
 import { perUserFollowingChart } from '@/services/chart/index';
 import { genId } from '@/misc/gen-id';
+import { IdentifiableError } from '@/misc/identifiable-error';
 
 export default async function(blocker: User, blockee: User) {
+	if (blockee.isAdmin || blockee.isModerator) {
+		throw new IdentifiableError('e42b7890-5e4d-9d9c-d54b-cf4dd30adfb5');
+	}
+
 	await Promise.all([
 		cancelRequest(blocker, blockee),
 		cancelRequest(blockee, blocker),