diff --git a/src/components/Posts/PostItem.astro b/src/components/Posts/PostItem.astro
index c566a77..bc20998 100644
--- a/src/components/Posts/PostItem.astro
+++ b/src/components/Posts/PostItem.astro
@@ -12,11 +12,10 @@ const data = Astro.props;
 
       <div class="post-meta-row">
         <span class="post-date">{data.date}</span>
-
         <span class="post-stats">
-          <span class="post-stat"
-            >💬 <Remark42Count url=`${data.postPath}` client:idle /></span
-          >
+          <span class="post-stat">
+            💬 <Remark42Count url={data.postPath} client:idle />
+          </span>
         </span>
       </div>
     </div>
@@ -122,10 +121,38 @@ const data = Astro.props;
 
   @media (max-width: 640px) {
     .post-link {
-      gap: 0.75rem;
+      display: grid;
+      grid-template-columns: 1fr 120px;
+      grid-template-areas:
+        "title title"
+        "desc image"
+        "meta image";
+      column-gap: 0.75rem;
+      row-gap: 0.2rem;
+      align-items: start;
+    }
+
+    .post-text {
+      display: contents;
+      min-height: auto;
+    }
+
+    .post-title {
+      grid-area: title;
+      -webkit-line-clamp: 2;
+    }
+
+    .post-description {
+      grid-area: desc;
+    }
+
+    .post-meta-row {
+      grid-area: meta;
+      gap: 0.7rem;
     }
 
     .post-image {
+      grid-area: image;
       width: 120px;
       height: calc(120px * 9 / 16);
     }
diff --git a/src/layouts/BaseLayout.astro b/src/layouts/BaseLayout.astro
index 7b46e96..fc236b7 100644
--- a/src/layouts/BaseLayout.astro
+++ b/src/layouts/BaseLayout.astro
@@ -22,6 +22,48 @@ const {
 		<meta name="generator" content={Astro.generator} />
 		<title>{pageTitle}</title>
 	</head>
+	<div class="floating-actions">
+		<button
+			id="theme-toggle-fab"
+			aria-label="Toggle theme"
+			title="Toggle theme"
+		>
+			<svg
+				class="theme-toggle-icon"
+				viewBox="0 0 24 24"
+				width="20"
+				height="20"
+				aria-hidden="true"
+			>
+				<path
+					class="sun"
+					fill-rule="evenodd"
+					d="M12 17.5a5.5 5.5 0 1 0 0-11 5.5 5.5 0 0 0 0 11zm0 1.5a7 7 0 1 0 0-14 7 7 0 0 0 0 14zm12-7a.8.8 0 0 1-.8.8h-2.4a.8.8 0 0 1 0-1.6h2.4a.8.8 0 0 1 .8.8zM4 12a.8.8 0 0 1-.8.8H.8a.8.8 0 0 1 0-1.6h2.5a.8.8 0 0 1 .8.8zm16.5-8.5a.8.8 0 0 1 0 1l-1.8 1.8a.8.8 0 0 1-1-1l1.7-1.8a.8.8 0 0 1 1 0zM6.3 17.7a.8.8 0 0 1 0 1l-1.7 1.8a.8.8 0 1 1-1-1l1.7-1.8a.8.8 0 0 1 1 0zM12 0a.8.8 0 0 1 .8.8v2.5a.8.8 0 0 1-1.6 0V.8A.8.8 0 0 1 12 0zm0 20a.8.8 0 0 1 .8.8v2.4a.8.8 0 0 1-1.6 0v-2.4a.8.8 0 0 1 .8-.8zM3.5 3.5a.8.8 0 0 1 1 0l1.8 1.8a.8.8 0 1 1-1 1L3.5 4.6a.8.8 0 0 1 0-1zm14.2 14.2a.8.8 0 0 1 1 0l1.8 1.7a.8.8 0 0 1-1 1l-1.8-1.7a.8.8 0 0 1 0-1z"
+				></path>
+				<path
+					class="moon"
+					fill-rule="evenodd"
+					d="M16.5 6A10.5 10.5 0 0 1 4.7 16.4 8.5 8.5 0 1 0 16.4 4.7l.1 1.3zm-1.7-2a9 9 0 0 1 .2 2 9 9 0 0 1-11 8.8 9.4 9.4 0 0 1-.8-.3c-.4 0-.8.3-.7.7a10 10 0 0 0 .3.8 10 10 0 0 0 9.2 6 10 10 0 0 0 4-19.2 9.7 9.7 0 0 0-.9-.3c-.3-.1-.7.3-.6.7a9 9 0 0 1 .3.8z"
+				></path>
+			</svg>
+		</button>
+
+		<button id="back-to-top" aria-label="Back to top" title="Back to top">
+			<svg
+				viewBox="0 0 24 24"
+				width="20"
+				height="20"
+				fill="none"
+				stroke="currentColor"
+				stroke-width="2.2"
+				stroke-linecap="round"
+				stroke-linejoin="round"
+				aria-hidden="true"
+			>
+				<path d="M18 15l-6-6-6 6"></path>
+			</svg>
+		</button>
+	</div>
 	<body>
 		<Header />
 		<main class="page-content">
@@ -38,4 +80,184 @@ const {
 		width: 100%;
 		height: 100%;
 	}
+
+	.floating-actions {
+		position: fixed;
+		right: 1.25rem;
+		bottom: 1.25rem;
+		display: flex;
+		flex-direction: column;
+		gap: 0.75rem;
+		z-index: 1000;
+	}
+
+	#theme-toggle-fab,
+	#back-to-top {
+		width: 3rem;
+		height: 3rem;
+		border: #a7a7a7 2px solid;
+		border-radius: 999px;
+		background: rgba(255, 255, 255, 0.92);
+		color: #222;
+		box-shadow: 0 4px 14px rgba(0, 0, 0, 0.16);
+		cursor: pointer;
+		display: flex;
+		align-items: center;
+		justify-content: center;
+		backdrop-filter: blur(6px);
+	}
+
+	#theme-toggle-fab {
+		position: relative;
+	}
+
+	#theme-toggle-fab {
+		position: relative;
+	}
+
+	.theme-toggle-icon {
+		width: 1.2rem;
+		height: 1.2rem;
+		fill: currentColor;
+	}
+
+	.theme-toggle-icon .sun,
+	.theme-toggle-icon .moon {
+		transform-origin: center;
+		transition:
+			opacity 0.2s ease,
+			transform 0.2s ease;
+	}
+
+	.theme-toggle-icon .sun {
+		opacity: 1;
+		transform: scale(1) rotate(0deg);
+	}
+
+	.theme-toggle-icon .moon {
+		opacity: 0;
+		transform: scale(0.75) rotate(-20deg);
+	}
+
+	:global(.dark) .theme-toggle-icon .sun {
+		opacity: 0;
+		transform: scale(0.75) rotate(20deg);
+	}
+
+	:global(.dark) .theme-toggle-icon .moon {
+		opacity: 1;
+		transform: scale(1) rotate(0deg);
+	}
+
+	#theme-toggle-fab,
+	#back-to-top {
+		opacity: 0;
+		visibility: hidden;
+		transform: translateY(10px);
+		transition:
+			opacity 0.2s ease,
+			transform 0.2s ease,
+			visibility 0.2s ease;
+	}
+
+	#theme-toggle-fab.show,
+	#back-to-top.show {
+		opacity: 1;
+		visibility: visible;
+		transform: translateY(0);
+	}
+
+	#theme-toggle-fab.show:hover,
+	#back-to-top.show:hover {
+		transform: translateY(-2px);
+	}
+
+	:global(.dark) #theme-toggle-fab,
+	:global(.dark) #back-to-top {
+		background: rgba(34, 34, 34, 0.92);
+		color: #f5f5f5;
+		box-shadow: 0 4px 14px rgba(0, 0, 0, 0.32);
+		border: #515151 2px solid;
+	}
+
+	@media (max-width: 640px) {
+		.floating-actions {
+			right: 1rem;
+			bottom: 1rem;
+			gap: 0.65rem;
+		}
+
+		#theme-toggle-fab,
+		#back-to-top {
+			width: 2.75rem;
+			height: 2.75rem;
+		}
+	}
 </style>
+
+<script>
+	const initFloatingActions = () => {
+		const backToTop = document.getElementById("back-to-top");
+		const themeToggle = document.getElementById("theme-toggle-fab");
+
+		if (backToTop && backToTop.dataset.bound !== "true") {
+			const toggleBackToTop = () => {
+				if (window.scrollY > 300) {
+					backToTop.classList.add("show");
+				} else {
+					backToTop.classList.remove("show");
+				}
+			};
+
+			backToTop.addEventListener("click", () => {
+				window.scrollTo({
+					top: 0,
+					behavior: "smooth",
+				});
+			});
+
+			window.addEventListener("scroll", toggleBackToTop, {
+				passive: true,
+			});
+			toggleBackToTop();
+			backToTop.dataset.bound = "true";
+		}
+
+		if (themeToggle && themeToggle.dataset.bound !== "true") {
+			const togglethemeToggle = () => {
+				if (window.scrollY > 300) {
+					themeToggle.classList.add("show");
+				} else {
+					themeToggle.classList.remove("show");
+				}
+			};
+
+			const root = document.documentElement;
+
+			const applyTheme = (theme: string) => {
+				if (theme === "dark") {
+					root.classList.add("dark");
+					localStorage.setItem("color-theme", "dark");
+				} else {
+					root.classList.remove("dark");
+					localStorage.setItem("color-theme", "light");
+				}
+			};
+
+			themeToggle.addEventListener("click", () => {
+				const isDark = root.classList.contains("dark");
+				applyTheme(isDark ? "light" : "dark");
+			});
+
+			window.addEventListener("scroll", togglethemeToggle, {
+				passive: true,
+			});
+
+			togglethemeToggle();
+			themeToggle.dataset.bound = "true";
+		}
+	};
+
+	initFloatingActions();
+	document.addEventListener("astro:page-load", initFloatingActions);
+</script>
diff --git a/src/layouts/MarkdownPostLayout.astro b/src/layouts/MarkdownPostLayout.astro
index 24f8562..fbe9d39 100644
--- a/src/layouts/MarkdownPostLayout.astro
+++ b/src/layouts/MarkdownPostLayout.astro
@@ -14,6 +14,27 @@ const t = getTranslations(lang);
   description={frontmatter.description}
   image={frontmatter.image?.url}
 >
+  <a
+    href="/"
+    class="back-button"
+    id="back-button"
+    aria-label="Go back"
+    title="返回"
+  >
+    <svg
+      viewBox="0 0 24 24"
+      width="20"
+      height="20"
+      fill="none"
+      stroke="currentColor"
+      stroke-width="2.2"
+      stroke-linecap="round"
+      stroke-linejoin="round"
+      aria-hidden="true"
+    >
+      <path d="M15 18l-6-6 6-6"></path>
+    </svg>
+  </a>
   <article class="post-article">
     <div class="post-header">
       <div class="post-meta">
@@ -81,7 +102,97 @@ const t = getTranslations(lang);
   })}
 />
 
+<script>
+  const initFloatingActions = () => {
+    const backButton = document.getElementById("back-button");
+
+    if (backButton && backButton.dataset.bound !== "true") {
+      const toggleBackButton = () => {
+        if (window.scrollY > 300) {
+          backButton.classList.add("show");
+        } else {
+          backButton.classList.remove("show");
+        }
+      };
+
+      backButton.addEventListener("click", () => {
+        if (window.history.length > 1) {
+          window.history.back();
+        } else {
+          window.location.href = "/";
+        }
+      });
+
+      window.addEventListener("scroll", toggleBackButton, {
+        passive: true,
+      });
+      toggleBackButton();
+      backButton.dataset.bound = "true";
+    }
+  };
+  initFloatingActions();
+  document.addEventListener("astro:page-load", initFloatingActions);
+</script>
+
 <style>
+  .back-button {
+    position: fixed;
+    top: 1.25rem;
+    left: 1.25rem;
+    width: 3rem;
+    height: 3rem;
+    border-radius: 999px;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    text-decoration: none;
+    border: #285ee9 2px solid;
+    background: rgba(255, 255, 255, 0.92);
+    color: #222;
+    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.16);
+    backdrop-filter: blur(6px);
+    z-index: 1000;
+    visibility: hidden;
+    transform: translateY(10px);
+    opacity: 0;
+    transition:
+      opacity 0.2s ease,
+			transform 0.2s ease,
+			visibility 0.2s ease;
+      box-shadow 0.2s ease,
+      background 0.2s ease,
+      color 0.2s ease;
+  }
+
+  .back-button.show {
+    opacity: 1;
+    visibility: visible;
+    transform: translateY(0);
+  }
+
+  .back-button.show:hover {
+    transform: translateY(-2px);
+  }
+
+  .back-button:hover {
+    transform: translateY(-2px);
+  }
+
+  :global(.dark) .back-button {
+    background: rgba(34, 34, 34, 0.92);
+    color: #f5f5f5;
+    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.32);
+    border: #2f406d 2px solid;
+  }
+
+  @media (max-width: 640px) {
+    .back-button {
+      top: 1rem;
+      left: 1rem;
+      width: 2.75rem;
+      height: 2.75rem;
+    }
+  }
   .post-content {
     font-family:
       system-ui,
diff --git a/src/pages/[lang]/tags/[tag].astro b/src/pages/[lang]/tags/[tag].astro
index 948c76d..b2d0b09 100644
--- a/src/pages/[lang]/tags/[tag].astro
+++ b/src/pages/[lang]/tags/[tag].astro
@@ -44,9 +44,12 @@ const t = getTranslations(lang);
           .toISOString()
           .split("T")[0];
 
+        const [postLang, ...slugParts] = post.id.split("/");
+        const slug = slugParts.join("/");
+
         return (
           <PostItem
-            url={`/${lang}/posts/${post.id}/`}
+            url={`/${lang}/posts/${slug}/`}
             title={post.data.title}
             date={formattedDate}
             img={post.data.image.url}
diff --git a/src/styles/global.css b/src/styles/global.css
index 5f67659..4d170df 100644
--- a/src/styles/global.css
+++ b/src/styles/global.css
@@ -36,7 +36,7 @@ pre {
 
 code {
   font-family: "Maple Mono", monospace;
-  font-size: 0.92rem;
+  font-size: 0.96rem;
 }
 
 /* 行内代码 */
@@ -61,6 +61,7 @@ body {
   max-width: 90ch;
   padding: 1rem;
   line-height: 1.7;
+  font-size: 1.15rem;
 }
 
 body::after {
