diff --git a/src/ecmascript/spidermonkey/Makefile b/src/ecmascript/spidermonkey/Makefile
index b132d602..f99400b8 100644
--- a/src/ecmascript/spidermonkey/Makefile
+++ b/src/ecmascript/spidermonkey/Makefile
@@ -2,7 +2,7 @@ top_builddir=../../..
 include $(top_builddir)/Makefile.config
 INCLUDES += $(SPIDERMONKEY_CFLAGS)
 
-OBJS = attr.obj attributes.obj collection.obj console.obj document.obj element.obj form.obj forms.obj heartbeat.obj history.obj implementation.obj input.obj \
+OBJS = attr.obj attributes.obj collection.obj console.obj css.obj document.obj element.obj form.obj forms.obj heartbeat.obj history.obj implementation.obj input.obj \
 	keyboard.obj localstorage.obj location.obj message.obj navigator.obj nodelist.obj screen.obj style.obj unibar.obj window.obj xhr.obj
 
 include $(top_srcdir)/Makefile.lib
diff --git a/src/ecmascript/spidermonkey/css.cpp b/src/ecmascript/spidermonkey/css.cpp
new file mode 100644
index 00000000..a5588df9
--- /dev/null
+++ b/src/ecmascript/spidermonkey/css.cpp
@@ -0,0 +1,268 @@
+/* The SpiderMonkey html CSSStyleDeclaration object implementation. */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "elinks.h"
+
+#include "ecmascript/libdom/dom.h"
+
+#include "ecmascript/spidermonkey/util.h"
+#include <jsfriendapi.h>
+
+#include "bfu/dialog.h"
+#include "cache/cache.h"
+#include "cookies/cookies.h"
+#include "dialogs/menu.h"
+#include "dialogs/status.h"
+#include "document/html/frames.h"
+#include "document/document.h"
+#include "document/forms.h"
+#include "document/libdom/corestrings.h"
+#include "document/view.h"
+#include "ecmascript/ecmascript.h"
+#include "ecmascript/spidermonkey/css.h"
+#include "ecmascript/spidermonkey/element.h"
+#include "intl/libintl.h"
+#include "main/select.h"
+#include "osdep/newwin.h"
+#include "osdep/sysname.h"
+#include "protocol/http/http.h"
+#include "protocol/uri.h"
+#include "session/history.h"
+#include "session/location.h"
+#include "session/session.h"
+#include "session/task.h"
+#include "terminal/tab.h"
+#include "terminal/terminal.h"
+#include "util/conv.h"
+#include "util/memory.h"
+#include "util/string.h"
+#include "viewer/text/draw.h"
+#include "viewer/text/form.h"
+#include "viewer/text/link.h"
+#include "viewer/text/vs.h"
+
+#include <iostream>
+#include <algorithm>
+#include <string>
+
+
+static bool CSSStyleDeclaration_item(JSContext *ctx, unsigned int argc, JS::Value *rval);
+static bool CSSStyleDeclaration_namedItem(JSContext *ctx, unsigned int argc, JS::Value *rval);
+static bool CSSStyleDeclaration_item2(JSContext *ctx, JS::HandleObject hobj, int index, JS::MutableHandleValue hvp);
+static bool CSSStyleDeclaration_namedItem2(JSContext *ctx, JS::HandleObject hobj, char *str, JS::MutableHandleValue hvp);
+
+static void CSSStyleDeclaration_finalize(JS::GCContext *op, JSObject *obj)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+}
+
+JSClassOps CSSStyleDeclaration_ops = {
+	nullptr,  // addProperty
+	nullptr,  // deleteProperty
+	nullptr,  // enumerate
+	nullptr,  // newEnumerate
+	nullptr,  // resolve
+	nullptr,  // mayResolve
+	CSSStyleDeclaration_finalize, // finalize
+	nullptr,  // call
+	nullptr,  // construct
+	JS_GlobalObjectTraceHook
+};
+
+JSClass CSSStyleDeclaration_class = {
+	"CSSStyleDeclaration",
+	JSCLASS_HAS_RESERVED_SLOTS(1),
+	&CSSStyleDeclaration_ops
+};
+
+static const spidermonkeyFunctionSpec CSSStyleDeclaration_funcs[] = {
+	{ "item",		CSSStyleDeclaration_item,		1 },
+	{ "namedItem",		CSSStyleDeclaration_namedItem,	1 },
+	{ NULL }
+};
+
+static bool CSSStyleDeclaration_get_property_length(JSContext *ctx, unsigned int argc, JS::Value *vp);
+
+static JSPropertySpec CSSStyleDeclaration_props[] = {
+	JS_PSG("length",	CSSStyleDeclaration_get_property_length, JSPROP_ENUMERATE),
+	JS_PS_END
+};
+
+static bool
+CSSStyleDeclaration_get_property_length(JSContext *ctx, unsigned int argc, JS::Value *vp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::CallArgs args = CallArgsFromVp(argc, vp);
+	JS::RootedObject hobj(ctx, &args.thisv().toObject());
+
+	struct view_state *vs;
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	args.rval().setInt32(3); // fake
+
+	return true;
+}
+
+static bool
+CSSStyleDeclaration_item(JSContext *ctx, unsigned int argc, JS::Value *vp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::Value val;
+	JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+	JS::RootedObject hobj(ctx, &args.thisv().toObject());
+	JS::RootedValue rval(ctx, val);
+
+	int index = args[0].toInt32();
+	bool ret = CSSStyleDeclaration_item2(ctx, hobj, index, &rval);
+	args.rval().set(rval);
+
+	return ret;
+}
+
+static bool
+CSSStyleDeclaration_namedItem(JSContext *ctx, unsigned int argc, JS::Value *vp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::Value val;
+	JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+	JS::RootedObject hobj(ctx, &args.thisv().toObject());
+	JS::RootedValue rval(ctx, val);
+
+	char *str = jsval_to_string(ctx, args[0]);
+	rval.setNull();
+	bool ret = CSSStyleDeclaration_namedItem2(ctx, hobj, str, &rval);
+	args.rval().set(rval);
+
+	mem_free_if(str);
+
+	return ret;
+}
+
+static bool
+CSSStyleDeclaration_item2(JSContext *ctx, JS::HandleObject hobj, int idx, JS::MutableHandleValue hvp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+
+	if (!JS_InstanceOf(ctx, hobj, &CSSStyleDeclaration_class, NULL)) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	hvp.setString(JS_NewStringCopyZ(ctx, "0")); // fake
+
+	return true;
+}
+
+static bool
+CSSStyleDeclaration_namedItem2(JSContext *ctx, JS::HandleObject hobj, char *str, JS::MutableHandleValue hvp)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+
+	if (!JS_InstanceOf(ctx, hobj, &CSSStyleDeclaration_class, NULL)) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	hvp.setString(JS_NewStringCopyZ(ctx, "0")); // fake
+
+	return true;
+}
+
+static bool
+CSSStyleDeclaration_set_items(JSContext *ctx, JS::HandleObject hobj, void *node)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+
+	/* This can be called if @obj if not itself an instance of the
+	 * appropriate class but has one in its prototype chain.  Fail
+	 * such calls.  */
+	if (!JS_InstanceOf(ctx, hobj, &CSSStyleDeclaration_class, NULL)) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	JS::RootedString zero(ctx, JS_NewStringCopyZ(ctx, "0"));
+	JS_DefineProperty(ctx, hobj, "marginTop", zero, JSPROP_ENUMERATE);
+	JS_DefineProperty(ctx, hobj, "marginLeft", zero, JSPROP_ENUMERATE);
+	JS_DefineProperty(ctx, hobj, "marginRight", zero, JSPROP_ENUMERATE);
+
+	return true;
+}
+
+JSObject *
+getCSSStyleDeclaration(JSContext *ctx, void *node)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JSObject *el = JS_NewObject(ctx, &CSSStyleDeclaration_class);
+
+	if (!el) {
+		return NULL;
+	}
+
+	JS::RootedObject r_el(ctx, el);
+
+	JS_DefineProperties(ctx, r_el, (JSPropertySpec *) CSSStyleDeclaration_props);
+	spidermonkey_DefineFunctions(ctx, el, CSSStyleDeclaration_funcs);
+
+	JS::SetReservedSlot(el, 0, JS::PrivateValue(node));
+	CSSStyleDeclaration_set_items(ctx, r_el, node);
+
+	return el;
+}
diff --git a/src/ecmascript/spidermonkey/css.h b/src/ecmascript/spidermonkey/css.h
new file mode 100644
index 00000000..60be7ab2
--- /dev/null
+++ b/src/ecmascript/spidermonkey/css.h
@@ -0,0 +1,8 @@
+#ifndef EL__ECMASCRIPT_SPIDERMONKEY_CSS_H
+#define EL__ECMASCRIPT_SPIDERMONKEY_CSS_H
+
+#include "ecmascript/spidermonkey/util.h"
+
+JSObject *getCSSStyleDeclaration(JSContext *ctx, void *node);
+
+#endif
diff --git a/src/ecmascript/spidermonkey/meson.build b/src/ecmascript/spidermonkey/meson.build
index bddea675..5fe14e94 100644
--- a/src/ecmascript/spidermonkey/meson.build
+++ b/src/ecmascript/spidermonkey/meson.build
@@ -1,2 +1,2 @@
-srcs += files('attr.cpp', 'attributes.cpp', 'collection.cpp', 'console.cpp', 'document.cpp', 'element.cpp', 'form.cpp', 'forms.cpp', 'heartbeat.cpp', 'history.cpp', 'implementation.cpp', 'input.cpp', 'keyboard.cpp',
+srcs += files('attr.cpp', 'attributes.cpp', 'collection.cpp', 'console.cpp', 'css.cpp', 'document.cpp', 'element.cpp', 'form.cpp', 'forms.cpp', 'heartbeat.cpp', 'history.cpp', 'implementation.cpp', 'input.cpp', 'keyboard.cpp',
 'localstorage.cpp', 'location.cpp', 'message.cpp', 'navigator.cpp', 'nodelist.cpp', 'screen.cpp', 'style.cpp', 'unibar.cpp', 'window.cpp', 'xhr.cpp')
diff --git a/src/ecmascript/spidermonkey/window.cpp b/src/ecmascript/spidermonkey/window.cpp
index 1073715b..58587397 100644
--- a/src/ecmascript/spidermonkey/window.cpp
+++ b/src/ecmascript/spidermonkey/window.cpp
@@ -10,6 +10,8 @@
 
 #include "elinks.h"
 
+#include "ecmascript/libdom/dom.h"
+
 #include "ecmascript/spidermonkey/util.h"
 #include <js/BigInt.h>
 #include <js/Conversions.h>
@@ -24,6 +26,7 @@
 #include "document/forms.h"
 #include "document/view.h"
 #include "ecmascript/ecmascript.h"
+#include "ecmascript/spidermonkey/css.h"
 #include "ecmascript/spidermonkey/heartbeat.h"
 #include "ecmascript/spidermonkey/keyboard.h"
 #include "ecmascript/spidermonkey/location.h"
@@ -169,6 +172,7 @@ void location_goto(struct document_view *doc_view, char *url);
 static bool window_addEventListener(JSContext *ctx, unsigned int argc, JS::Value *rval);
 static bool window_alert(JSContext *ctx, unsigned int argc, JS::Value *rval);
 static bool window_clearTimeout(JSContext *ctx, unsigned int argc, JS::Value *rval);
+static bool window_getComputedStyle(JSContext *ctx, unsigned int argc, JS::Value *rval);
 static bool window_open(JSContext *ctx, unsigned int argc, JS::Value *rval);
 static bool window_postMessage(JSContext *ctx, unsigned int argc, JS::Value *rval);
 static bool window_removeEventListener(JSContext *ctx, unsigned int argc, JS::Value *rval);
@@ -178,6 +182,7 @@ const spidermonkeyFunctionSpec window_funcs[] = {
 	{ "addEventListener", window_addEventListener, 3 },
 	{ "alert",	window_alert,		1 },
 	{ "clearTimeout",	window_clearTimeout,	1 },
+	{ "getComputedStyle",	window_getComputedStyle,	2 },
 	{ "open",	window_open,		3 },
 	{ "postMessage",	window_postMessage,	3 },
 	{ "removeEventListener", window_removeEventListener, 3 },
@@ -645,6 +650,35 @@ window_clearTimeout(JSContext *ctx, unsigned int argc, JS::Value *rval)
 	return true;
 }
 
+/* @window_funcs{"getComputedStyle"} */
+static bool
+window_getComputedStyle(JSContext *ctx, unsigned int argc, JS::Value *rval)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	JS::Realm *comp = js::GetContextRealm(ctx);
+
+	if (!comp) {
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s %d\n", __FILE__, __FUNCTION__, __LINE__);
+#endif
+		return false;
+	}
+	if (argc < 1) {
+		return true;
+	}
+
+	JS::CallArgs args = JS::CallArgsFromVp(argc, rval);
+	JS::RootedObject node(ctx, &args[0].toObject());
+	dom_node *el = (dom_node *)JS::GetMaybePtrFromReservedSlot<dom_node>(node, 0);
+	JSObject *css = getCSSStyleDeclaration(ctx, el);
+	args.rval().setObject(*css);
+
+	return true;
+}
+
+
 #if 0
 static bool
 window_get_property_closed(JSContext *ctx, JS::HandleObject hobj, JS::HandleId hid, JS::MutableHandleValue hvp)