diff --git a/assets/css/frontend/nav/base.css b/assets/css/frontend/nav/base.css
index af8529ce..11691006 100644
--- a/assets/css/frontend/nav/base.css
+++ b/assets/css/frontend/nav/base.css
@@ -195,7 +195,23 @@ body.dark-theme .site-nav--blur.is-scrolled {
   white-space: nowrap;
 }
 
-/* Light/dark logo toggle */
+/* Light/dark logo: single adaptive img (white-src/dark-src via theme.js) */
+.navbar-logo > img,
+.navbar-logo .site-brand__logo-img,
+.site-brand .site-brand__logo-img,
+.site-brand__logo-img,
+.site-brand .navbar-logo img {
+  height: 36px !important;
+  width: auto !important;
+  max-width: min(180px, 40vw) !important;
+  max-height: 36px !important;
+  padding: 0 !important;
+  object-fit: contain !important;
+  display: inline-block;
+  vertical-align: middle;
+}
+
+/* Legacy dual-img classes (if any remain elsewhere) */
 .site-brand__logo-img--dark {
   display: none;
 }
diff --git a/header.php b/header.php
index e239b1d6..ff1477a9 100644
--- a/header.php
+++ b/header.php
@@ -170,15 +170,17 @@ if (!empty($aksrt_bg_styles)) {
 		$aksrt_nav_styles[] = '--nav-max-width:' . (int) $aksrt_header_settings['max_width'] . 'px';
 	}
 	$aksrt_logo_parts = [];
-	if ($aksrt_logo_url !== '') {
-		$aksrt_logo_parts[] = '<img class="site-brand__logo-img site-brand__logo-img--light" src="' . esc_url($aksrt_logo_url) . '" alt="' . esc_attr($aksrt_brand_name) . '"' . ($aksrt_logo_width > 0 ? ' style="height:36px;width:auto;max-width:' . max(36, (int) $aksrt_logo_width) . 'px"' : '') . '>';
-		$aksrt_brand_logo_src = $aksrt_logo_url;
-	}
-	if ($aksrt_logo_dark_url !== '') {
-		$aksrt_logo_parts[] = '<img class="site-brand__logo-img site-brand__logo-img--dark" src="' . esc_url($aksrt_logo_dark_url) . '" alt="' . esc_attr($aksrt_brand_name) . '"' . ($aksrt_logo_width > 0 ? ' style="height:36px;width:auto;max-width:' . max(36, (int) $aksrt_logo_width) . 'px"' : '') . '>';
-		if ($aksrt_brand_logo_src === '') {
-			$aksrt_brand_logo_src = $aksrt_logo_dark_url;
+	if ($aksrt_logo_url !== '' || $aksrt_logo_dark_url !== '') {
+		$aksrt_logo_more = $aksrt_logo_width > 0
+			? 'style="height:36px;width:auto;max-width:' . max(36, (int) $aksrt_logo_width) . 'px"'
+			: 'style="height:36px;width:auto"';
+		$aksrt_logo_html = function_exists('aksrt_get_adaptive_theme_img')
+			? aksrt_get_adaptive_theme_img($aksrt_logo_url, $aksrt_logo_dark_url, $aksrt_brand_name, $aksrt_logo_more)
+			: '';
+		if ($aksrt_logo_html !== '') {
+			$aksrt_logo_parts[] = $aksrt_logo_html;
 		}
+		$aksrt_brand_logo_src = $aksrt_logo_url !== '' ? $aksrt_logo_url : $aksrt_logo_dark_url;
 	}
 	$aksrt_has_brand_logo = !empty($aksrt_logo_parts);
 	if ($aksrt_has_brand_logo) {