diff --git a/assets/css/frontend/single-post/author-actions.css b/assets/css/frontend/single-post/author-actions.css
index 50f919fc..96fbb8e8 100644
--- a/assets/css/frontend/single-post/author-actions.css
+++ b/assets/css/frontend/single-post/author-actions.css
@@ -335,6 +335,59 @@ html.dark .share-item {
 .theme-dark .share-item[data-platform="copy"]:hover { background: rgba(255,255,255,0.06); color: #ccc; }
 .theme-dark .share-item[data-platform="poster"]:hover { background: rgba(245,158,11,0.12); color: #f59e0b; }
 
+/* Narrow screens: bottom sheet so dropdown never clips off-screen */
+@media (max-width: 767px) {
+  .share-dropdown {
+    position: fixed;
+    left: 0;
+    right: 0;
+    bottom: 0;
+    top: auto;
+    transform: none;
+    width: 100%;
+    max-width: none;
+    z-index: 1200;
+    padding: 0 0 calc(12px + env(safe-area-inset-bottom, 0px));
+    background: transparent;
+  }
+  .share-dropdown[aria-hidden="false"] {
+    animation: shareSheetIn 0.22s ease-out forwards;
+  }
+  @keyframes shareSheetIn {
+    from { opacity: 0; transform: translateY(16px); }
+    to { opacity: 1; transform: translateY(0); }
+  }
+  .share-dropdown__grid {
+    justify-content: space-around;
+    flex-wrap: wrap;
+    gap: 6px;
+    margin: 0 10px;
+    padding: 14px 12px 16px;
+    border-radius: 14px 14px 10px 10px;
+    box-shadow: 0 -6px 28px rgba(0, 0, 0, 0.16);
+  }
+  .share-item {
+    min-width: 64px;
+    flex: 1 1 28%;
+    max-width: 33%;
+  }
+  #share-qrcode-box {
+    position: static;
+    margin: 10px auto 0;
+    transform: none;
+  }
+  body.aksrt-share-sheet-open {
+    overflow: hidden;
+  }
+  body.aksrt-share-sheet-open::before {
+    content: '';
+    position: fixed;
+    inset: 0;
+    background: rgba(0, 0, 0, 0.35);
+    z-index: 1190;
+  }
+}
+
 .theme-dark .post-drop-meta__menu,
 html.dark .post-drop-meta__menu {
     background: var(--surface-1, #323335);
diff --git a/assets/js/post-share.js b/assets/js/post-share.js
index dd0234b3..56e95fcd 100644
--- a/assets/js/post-share.js
+++ b/assets/js/post-share.js
@@ -135,7 +135,8 @@
 
     function closeDropdown() {
       dropdown.setAttribute('aria-hidden', 'true');
-      trigger.setAttribute('aria-expanded', 'false');
+      triggers.forEach(function (t) { t.setAttribute('aria-expanded', 'false'); });
+      document.body.classList.remove('aksrt-share-sheet-open');
       if (window.AksrtShare && typeof window.AksrtShare.hideQrFallback === 'function') {
         window.AksrtShare.hideQrFallback(qrBox);
       } else if (qrBox) {
@@ -152,7 +153,10 @@
       }
 
       dropdown.setAttribute('aria-hidden', 'false');
-      trigger.setAttribute('aria-expanded', 'true');
+      triggers.forEach(function (t) { t.setAttribute('aria-expanded', 'true'); });
+      if (window.matchMedia && window.matchMedia('(max-width: 767px)').matches) {
+        document.body.classList.add('aksrt-share-sheet-open');
+      }
     }
 
     trigger.addEventListener('click', function (event) {
diff --git a/inc/helpers/aksrt-template-tags.php b/inc/helpers/aksrt-template-tags.php
index 17ee5b9a..0bcd31d8 100644
--- a/inc/helpers/aksrt-template-tags.php
+++ b/inc/helpers/aksrt-template-tags.php
@@ -1357,16 +1357,33 @@ if (!function_exists('aksrt_render_footer_tabbar_single_extend')) :
 		endif;
 
 		if ($share_on) :
+			$share_title = get_the_title($post_id);
+			$share_url = get_permalink($post_id) ?: '';
+			$share_image = get_the_post_thumbnail_url($post_id, 'large') ?: '';
 			?>
 			<button type="button"
 				class="tabbar-item single-action-tabbar action-share"
 				data-type="share"
+				data-share-title="<?php echo esc_attr((string) $share_title); ?>"
+				data-share-url="<?php echo esc_url((string) $share_url); ?>"
+				<?php if ($share_image !== '') : ?>data-share-image="<?php echo esc_url((string) $share_image); ?>"<?php endif; ?>
 				aria-haspopup="true"
 				aria-expanded="false"
 				aria-label="<?php esc_attr_e('分享', 'aksrt'); ?>">
 				<i class="fas fa-share-alt" aria-hidden="true"></i>
 				<?php if ($show_text) : ?><span><?php esc_html_e('分享', 'aksrt'); ?></span><?php endif; ?>
 			</button>
+			<button type="button"
+				class="tabbar-item single-action-tabbar action-poster"
+				data-type="poster"
+				data-share-platform="poster"
+				data-share-title="<?php echo esc_attr((string) $share_title); ?>"
+				data-share-url="<?php echo esc_url((string) $share_url); ?>"
+				<?php if ($share_image !== '') : ?>data-share-image="<?php echo esc_url((string) $share_image); ?>"<?php endif; ?>
+				aria-label="<?php esc_attr_e('海报', 'aksrt'); ?>">
+				<i class="fas fa-image" aria-hidden="true"></i>
+				<?php if ($show_text) : ?><span><?php esc_html_e('海报', 'aksrt'); ?></span><?php endif; ?>
+			</button>
 			<?php
 		endif;