html - 桌面屏幕尺寸的背景图片太小？

Question

嘿， friend 们，当我将屏幕宽度设置为 2560 像素时，我注意到背景图像不会拉伸(stretch)整个屏幕宽度，这是我假设的标准桌面屏幕尺寸。我不确定这是我第一次进行媒体查询。我也不知道如何在此处或 Imgur 上上传图片，以便您可以看到它的实际效果。所以这是一张照片

https://jsfiddle.net/khcwnm90/同样，在 SO 上发布的代码只是为了让我可以发布 fiddle 链接。我认为我必须这样做非常愚蠢，因为我发布 fiddle 链接的唯一原因是我有太多代码要发布在这里。

body, html {
	margin: 0;
	padding: 0;
}

/*---HEADER---*/

li a {
	text-decoration-line: none;
	color: rgba(102,102,102,0.75);
}

header {
	background-image: url(../img/wall2.jpeg);
	height: 100vh;
	background-attachment: fixed;
	background-repeat: no-repeat;
	display: flex;
	justify-content: center;
	align-items: center;
}

nav {
	background-color: white;
	width: 100%;
	display: flex;
	justify-content: space-between;
	align-items: center;
	position: fixed;
	top: 0;
	left: 0;
	z-index: 2;
	box-shadow: 0px 0px 100px grey;
}

ul {
	margin-right: 30px;
	margin-top: 25px;
}

li {
	display: inline-block;
	font-size: 1.55rem;
	margin-right: 20px;
	font-family: 'Rajdhani';
}

li a:hover {
	cursor: pointer;
	color: #1a1a1a;
	transition: all 0.7s ease;
}

.after:after {
	position: relative;
	left: 12px;
	top: 2px;
	display: inline-block;
	content: "";
	width: 1px;
	height: 20px;
	background-color: rgba(102,102,102,0.25);
}

.logo {	color: red;
	font-size: 3.7rem;
	margin: 10px;
	opacity: 1;
	margin-left: 30px;
}

.phrase {
	text-align: center;
}

.phrase p {
	color: white;
	font-size: 3.5rem;
	font-family: 'Arvo';
	margin-bottom: 30px;

}

.phrase a {
	background-color: red;
	border-radius: 25px;
	color: white;
	font-family: 'Bitter';
	font-size: 1.8rem;
	padding-left: 15px;
	padding-right: 15px;
	padding-bottom: 10px;
	padding-top: 10px;
	transition: all 0.2s ease;
}

.phrase a:hover {
	transition: all 0.5s ease;
	background-color: #cc0000;
	cursor: pointer;
}

.phrase .fas {
	display: block;
	color: white;
	font-size: 3.5rem;
	margin-top: 15px;
}

/*---PROMISE---*/

.stats {
	width: 100%;
	display: flex;
	box-shadow: 0px 0px 150px grey;
	position: relative;
	z-index: 1;
	background-color: white;
}

.stats div {
	display: inline-block;
	flex-basis: 35%;
	text-align: center;
	padding-bottom: 30px;
}

.stat-info {
	font-size: 2rem;
	color: rgba(102,102,102, 1);
	font-family: 'Rajdhani';
	margin-bottom: 0;
	margin-top: 10px;
}

.stat-num {
	color: red;
	font-family: 'Rajdhani';
	font-size: 3rem;
	margin: 0;
	font-weight: bolder;
}

.stats div:before {
	display: inline-block;
	content: '';
	width: 2px;
	height: 35px;
	background-color: rgba(102,102,102, 0.60);
}

.promise {
	width: 100%;
	background-image: url('../img/concrete.jpg');
	background-position: center;
	background-attachment: fixed;
	background-size: cover;
}

.promise .wrapper {
	width: 100%;
	background-color: rgba(0, 0, 0, 0.3);
}

.promise h1 {
	position: relative;
	top: 40px;
	color: white;
	font-family: 'Arvo';
	font-size: 3.5rem;
	text-align: center;
	margin-top: 0;
	word-spacing: 7px;
	text-shadow: 0px 0px 100px grey;
}

.promise p {
	color: white;
	font-size: 1.8rem;
	font-family: 'Rajdhani';
	margin-bottom: 0;
	padding-bottom: 60px;
	text-align: center;
	margin-top: 40px;
	padding-left: 50px;
	padding-right: 50px;
}

/*---FOOTER---*/

.footer .wrapper {
	display: flex;
}

.footer div {
	display: inline-block;
	flex-basis: 33.33%;
	font-family: 'Rajdhani';
	color: rgba(102,102,102, 1);
	margin-top: 5px;
}

.footer h1 {
	font-size: 2rem;
	margin-top: 15px;
}

.footer .inner {
	margin-left: 55px;
}

.social .inner {
	margin-left: 45px;
}

.contact .inner {
	margin-left: 35px;
}

.footer .inner:before {
	display: inline-block;
	content: '';
	width: 27.1%;
	height: 2px;
	background-color: rgba(102,102,102, 0.6);
	position: absolute;
	margin-top: 54px;
}

.footer h1 span {
  display: inline;
  position: relative;
}

.footer h1 span:after {
  content: '';
  height: 2px;
  width: 100%;
  background-color: red;
  position: absolute;
  bottom: 0;
  left: 0;
}

.wrap:before {
	content: '';
	width: 100px;
	height: 2px;
	background-color: red;
	position: absolute;
	margin-top: 55px;
}

.links a {
	display: block;
	text-decoration-line: none;
	color: rgba(102,102,102, 1);
	font-size: 1.2rem;
	position: relative;
	top: -10px;
	transition: color 0.4s ease;
}

.links a:hover {
	color: red;
}

.contact p {
	position: relative;
	top: -10px;
}

.social i {
	font-size: 1.7rem;
	margin-right: 5px;
	position: relative;
	top: -20px;
	color: rgba(102,102,102, 0.7);
	transition: all 0.4s ease;
}

.social i:hover {
	color: red;
	cursor: pointer;
}

#msg {
	margin-top: -15px;
}

.footer-textarea {
	background-color: rgba(102,102,102, 0.2);
	outline: none;
	color: rgba(102,102,102, 1);
	resize: none;
	width: 89%;
}

.footer button {
	float: right;
	margin-right: 9.5%;
	margin-top: -17px;
	border: none;
	font-family: 'Rajdhani';
	font-size: 1.2rem;
	transition: all ease 0.4s;
	outline: none;
}

button:hover {
	cursor: pointer;
	color: red;
}

.dark {
	color: red;
}

.copyright {
	position: absolute;
	background-color: white;
	text-align: center;
	width: 100%;
	margin-bottom: 0;
	font-size: 1.2rem;
	padding-bottom: 4px;
}



/*-------MEDIA QUERIES-------*/



/*---LAPTOP-LARGE---*/

@media screen and (min-width: 1440px) {

	/*---FOOTER---*/

	.footer button {
		margin-left: 16.5%;
	}

}

/*---LAPTOP---*/

@media screen and (max-width: 1024px) {

	/*---NAV---*/

	.logo {
		font-size: 3rem;
	}

	nav li {
		font-size: 2rem;
	}

	/*---MAIN---*/

	header {
		height: 100vh;
	}

	.phrase p {
		font-size: 3rem;
	}

	.phrase a {
		font-size: 1.5rem;
	}

	.stats p {
		font-size: 2rem;
	}
	
	/*---FOOTER---*/
	
	.footer .inner {
		margin-left: 30px;
	}

	.footer-textarea {
		width: 88%;
	}

	.footer button {
		margin-right: 10.25%;
	}

	.footer h1 span {
	  display: inline;
	  position: relative;
	}

	.footer h1 span:after {
	  content: '';
	  height: 2px;
	  width: 100%;
	  background-color: red;
	  position: absolute;
	  bottom: 0;
	  left: 0;
	}

}

@media screen and (max-width: 1024px) and (min-height: 1366px) {

	/*---MAIN---*/

	header {
		height: 80vh;
	}
}

@media screen and (max-width: 823px) {

	/*---MAIN---*/

	.phrase p {
		font-size: 3rem;
	}

}

/*------LANDSCAPE-MODE------*/

@media screen and (max-width: 812px) {

	/*---NAV---*/

	nav li {
		font-size: 1.7rem;
	}

	.logo {
		font-size: 2.7rem;
	}

	/*---MAIN---*/

	header {
		height: 100vh;
	}

	.stats p {
		font-size: 2rem;
	}

	.promise p {
		font-size: 1.3rem;
	}



	/*---FOOTER---*/

	.footer button {
		margin-left: 8.5%;
	}

	.contact .inner {
		margin-right: 20px;
	}

}

/*---TABLET---*/

@media screen and (max-width: 768px) {

	/*---NAV---*/

	nav li {
		font-size: 1.6rem;
	}

	.logo {
		font-size: 3rem;
	}

	/*---MAIN---*/

	.phrase {
		top: 300px;
	}

	/*---FOOTER---*/

	.footer h1 span {
	  display: inline;
	  position: relative;
	}

	.footer h1 span:after {
	  content: '';
	  height: 2px;
	  width: 100%;
	  background-color: red;
	  position: absolute;
	  bottom: 0;
	  left: 0;
	}

	.footer button {
		margin-left: 7.4%;
	}
}

@media screen and (max-width: 731px) {

	/*---FOOTER---*/

	.footer button {
		margin-left: 6%;
	}

	.contact .inner p {
		margin: 5px;
	}

}

/*------LANDSCAPE-MODE-MOBILE------*/

@media screen and (max-width: 715px) {
	
	/*---NAV---*/

	.phrase {
		margin-top: 30px;
	}

	.phrase p {
		font-size: 2.5rem;
	}

	.phrase a {
		font-size: 1.5rem;
	}

	nav ul {
		padding-left: 0;
		margin: 0;
	}

	nav li {
		font-size: 1.4rem;
	}

	nav .logo {
		font-size: 2.5rem;
	}

	/*---FOOTER---*/

	.links a {
		font-size: 1.1rem;
		top: -13px;
	}

	.contact .inner {
		margin-right: 15px;
	}

	.contact p {
		margin: 5px;
	}

	.footer-textarea {
		position: relative;
		top: -5px;
		width: 90.5%;
	}

	.footer button {
		margin-top: -18px;
		margin-right: 7%;
		font-size: 1.1rem;
	}
}

@media screen and (max-width: 586px) {

	/*---MAIN---*/

	.phrase p {
		font-size: 2.7rem;
	}

	.stats p {
		font-size: 1.5rem;
	}

	/*---FOOTER---*/

	.footer .wrapper {
		display: flex;
		flex-direction: column;
	}

	.footer div {
		margin: 0;
	}

	.footer h1 {
		font-size: 2rem;
		margin-top: 10px;
	}

	.footer .inner {
		margin: 0;
	}

	.footer .inner:before {
		display: inline-block;
		content: '';
		width: 100vw;
		height: 2px;
		background-color: rgba(102,102,102, 0.6);
		position: absolute;
		margin-top: 48px;
	}

	.footer h1 span:after {
	  content: '';
	  height: 2px;
	  width: 100%;
	  background-color: red;
	  position: absolute;
	  bottom: 1px;
	  left: 0;
	}

	.social .inner {
		position: relative;
		top: -10px;
	}

	.links a {
		margin-left: 5px;
	}

	.social h1 {
		margin-bottom: 10px;
	}

	#msg {
		font-size: 1rem;
		margin-bottom: 0;
		margin-right: 25.5%;
		position: absolute;
		right: 5px;
		top: 80px;
	}

	.footer button {
		right: 9.25%;
		margin-top: 0.2px;
	}

	.social i {
		font-size: 1.8rem;
		margin-right: 2px;
		position: relative;
		top: -5px;
		left: 5px;
		color: rgba(102,102,102, 0.7);
		transition: all 0.4s ease;
	}

	.footer-textarea {
		width: 88.5%;
		margin-top: 25px;
		margin-left: 5px;
	}

	.contact p {
		margin: 5px;
		font-size: 1.2rem;
	}

	.copyright {
		background-color: red;
		padding-top: 10px;
		padding-bottom: 10px;
	}

	.copyright span {
		color: white;
		background-color: red;
	}

}

@media screen and (max-width: 568px) {

	/*---MAIN---*/

	.phrase p {
		font-size: 2rem;
	}

	.phrase a {
		font-size: 1.3rem;
	}

	.stats p {
		font-size: 1.5rem;
	}

	.promise p {
		font-size: 1.3rem;
	}

	/*---FOOTER---*/

	.footer .wrapper {
		display: flex;
		flex-direction: column;
	}

	.footer div {
		margin: 0;
	}

	.footer h1 {
		font-size: 2rem;
		margin-top: 10px;
	}

	.footer .inner {
		margin: 0;
	}

	.footer .inner:before {
		display: inline-block;
		content: '';
		width: 100%;
		height: 2px;
		background-color: rgba(102,102,102, 0.6);
		position: absolute;
		margin-top: 48px;
	}

	.footer h1 span:after {
	  content: '';
	  height: 2px;
	  width: 100%;
	  background-color: red;
	  position: absolute;
	  bottom: 1px;
	  left: 0;
	}

	.social .inner {
		position: relative;
		top: -10px;
	}

	.social .inner:before {
		width: 100vw;
	}

	.links a {
		margin-left: 5px;
	}

	.social h1 {
		margin-bottom: 10px;
	}

	#msg {
		font-size: 1rem;
		margin-bottom: 0;
		margin-right: 25.5%;
		position: absolute;
		right: 5px;
		top: 80px;
	}

	.footer button {
		right: 9.25%;
		margin-top: 0.2px;
	}

	.social i {
		font-size: 1.8rem;
		margin-right: 2px;
		position: relative;
		top: -5px;
		left: 5px;
		color: rgba(102,102,102, 0.7);
		transition: all 0.4s ease;
	}

	.footer-textarea {
		width: 88.5%;
		margin-top: 30px;
		margin-left: 5px;
	}

	.contact p {
		margin: 5px;
		font-size: 1.2rem;
	}

	.copyright {
		background-color: red;
	}

	.copyright span {
		color: white;
		background-color: red;
	}
}

@media screen and (max-width: 517px) {

	/*---NAV---*/

	nav li {
		font-size: 1.1rem;
	}

	/*---MAIN---*/

	header h1 {
		font-size: 3rem;
	}

	/*---FOOTER---*/

	.footer .wrapper {
		display: flex;
		flex-direction: column;
	}

	.footer div {
		margin: 0;
	}

	.footer h1 {
		font-size: 2rem;
		margin-top: 10px;
	}

	.footer .inner {
		margin: 0;
	}

	.footer .inner:before {
		display: inline-block;
		content: '';
		width: 100vw;
		height: 2px;
		background-color: rgba(102,102,102, 0.6);
		position: absolute;
		margin-top: 48px;
	}

	.social .inner {
		position: relative;
		top: -10px;
	}

	.footer h1 span:after {
	    content: '';
	    height: 2px;
	    width: 100%;
	    background-color: red;
		position: absolute;
	  	bottom: 1px;
		left: 0;
	}

	.links a {
		margin-left: 5px;
	}

	.social h1 {
		margin-bottom: 10px;
	}

	#msg {
		font-size: 1.3rem;
		margin-bottom: 0;
		float: right;
		margin-right: 25.5%;
		position: relative;
		top: 15px;
	}

	.footer button {
		right: 9.25%;
		margin-top: 0.2px;
	}

	.social i {
		font-size: 1.8rem;
		margin-right: 7px;
		position: relative;
		top: -5px;
		left: 5px;
		color: rgba(102,102,102, 0.7);
		transition: all 0.4s ease;
	}

	.footer-textarea {
		width: 88.5%;
		margin-left: 5px;
		margin-top: 0px;
		position: relative;
		top: 10px;
	}

	.contact p {
		margin: 5px;
		font-size: 1.2rem;
	}

	.copyright {
		background-color: red;
	}

	.copyright span {
		color: white;
		background-color: red;
	}

}

/*---MOBILE---*/

@media screen and (max-width: 425px) {

	/*---NAV---*/

	.logo {
		font-size: 2.5rem;
		margin-left: 10px;
	}

	ul {
		margin: 0;
		padding: 0;
	}

	nav li {
		display: none;
	}

	.ham-menu {
		width: 55px;
		height: 55px;
		position: fixed;
		right: 0;
		top: 4px;
		display: flex;
		justify-content: center;
		align-items: center;
		flex-direction: column;
	}

	.m1, .m2, .m3 {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
		animation-duration: 0.3s;
		animation-fill-mode: forwards;
	}

	/*---MAIN---*/

	.phrase {
		top: 179px;
	}

	.phrase p {
		font-size: 2.5rem;
		margin-bottom: 10px;
	}

	.phrase a {
		font-size: 1.3rem;
		padding: 7px;
	}

	.phrase .fas {
		margin-top: 10px;
		font-size: 2.5rem;
	}

	.stats p {
		font-size: 1.3rem;
	}

	.stats div {
		padding-bottom: 10px;
	}

	.stats div:before {
		height: 20px;
	}

	.promise h1 {
		font-size: 2.7rem;
	}

	.promise p {
		position: relative;
		top: 10px;
		font-size: 1.3rem;
	}

	/*---FOOTER---*/

	.footer .wrapper {
		display: flex;
		flex-direction: column;
	}

	.footer div {
		margin: 0;
	}

	.footer h1 {
		font-size: 2rem;
		margin-top: 10px;
	}

	.footer .inner {
		margin: 0;
	}

	.footer .inner:before {
		display: inline-block;
		content: '';
		width: 100vw;
		height: 2px;
		background-color: rgba(102,102,102, 0.6);
		position: absolute;
		margin-top: 48px;
	}

	.social .inner {
		position: relative;
		top: -9.5px;
	}

	.footer h1 span {
	  display: inline;
	  position: relative;
	}

	.footer h1 span:after {
	  content: '';
	  height: 2px;
	  width: 100%;
	  background-color: red;
	  position: absolute;
	  bottom: 1px;
	  left: 0;
	}

	.links a {
		margin-left: 5px;
	}

	.social h1 {
		margin-bottom: 10px;
	}

	#msg {
		font-size: 1rem;
		margin-bottom: 0;
		margin-right: 25.5%;
		position: absolute;
		right: 5px;
		top: 80px;
	}

	.footer button {
		right: 9.25%;
		margin-top: 0.2px;
	}

	.social i {
		font-size: 1.8rem;
		margin-right: 2px;
		position: relative;
		top: -5px;
		left: 5px;
		color: rgba(102,102,102, 0.7);
		transition: all 0.4s ease;
	}

	.footer-textarea {
		width: 88.5%;
		margin-top: 0px;
		margin-left: 5px;
	}

	.contact p {
		margin: 5px;
		font-size: 1.2rem;
	}

	.copyright {
		background-color: red;
	}

	.copyright span {
		color: white;
		background-color: red;
	}

}

@media screen and (max-width: 360px) {
	.footer button {
		margin-right: 8.5%;
	}
}

/*---HAM-MENU-ANIMATIONS---*/

@keyframes m1 {
	from {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
	}
	to {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
		transform: rotate(45deg);
		position: relative;
		top: 12px;
	}
}

@keyframes m2 {
	from {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
	}
	to {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
		opacity: 0;
	}
}

@keyframes m3 {
	from {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
	}
	to {
		border-radius: 4px;
		margin: 4px;
		width: 35px;
		height: 3px;
		background-color: red;
		float: left;
		transform: rotate(-45deg);
		position: relative;
		top: -10.5px;
	}
}

Answer 1

.header 的新规则，删除 background-attachment: fixed; 并添加 background-size: cover;:

header {
  background-image: url(../img/wall2.jpeg);
  height: 100vh;
  background-size: cover;
  background-repeat: no-repeat;
  display: flex;
  justify-content: center;
  align-items: center;
}