我无法摆脱的HTML / CSS项目顶部有一个怪异的空白。我如何摆脱空白？尽管我已经将normalize.css中的边距和填充设置为0，所以即使不使用normalize.css文件也可以看到它，所以这不是问题。我制作了一个JSsnippet here，它可能更容易理解。
* {
margin: 0;
padding: 0;
border: 0;
outline: 0;
font-size: 100%;
vertical-align: baseline;
background: transparent;
box-sizing: border-box;
}
这是我的项目的HTML / CSS代码：
HTML：
<!DOCTYPE html>
<html>
<head>
<title>SuperMegaAwesome Landing Page | Matt Bell</title>
<link rel="stylesheet" type="text/css" href="./Stylesheets/CSS/main.css">
<link rel="stylesheet" type="text/css" href="./Stylesheets/CSS/normalize.css">
</head>
<body>
<header>
<p id="logo">Super<span>Mega</span>Awesome</p>
<nav>
<a href="#">Home</a>
<a href="#">Portfolio</a>
<a href="#">Services</a>
<a href="#">Get in touch</a>
</nav>
</header>
<section id="hero">
<div id="hero_overlay">
<div class="wrapper">
<div id="content">
<h1 class="title">We create beautiful products</h1>
<h2 class="sub_title">Truffaut DIY keffiyeh, twee messenger bag venmo locavore organic master cleanse marfa gochujang selvage</h2>
<div class="button_wrapper">
<a href="#" class="button button_highlight">Learn More</a>
<a href="#" class="button button_secondary">Play Video</a>
</div>
</div>
</div>
</div>
</section>
<div>hELLO</div>
<div>HELLOOO</div>
<footer>Hello</footer>
</body>
</html>
CSS：
body {
font-family: "Brandon Grotesque", Helvetica, sans-serif;
}
.wrapper {
width: 90vw;
height: 100%;
margin: 0 auto;
background-color: rgba(100, 100, 0, 0.4);
}
header {
position: fixed;
height: 10vh;
width: 100vw;
}
header #logo {
color: #FFFFFF;
font-weight: 700;
font-size: 1.35rem;
position: absolute;
left: 10vw;
top: 50%;
transform: translateY(-50%);
}
header #logo span {
font-weight: 300;
}
header nav {
position: absolute;
right: 10vw;
top: 50%;
transform: translateY(-50%);
}
header nav a {
color: #FFFFFF;
font-weight: 700;
text-decoration: none;
margin-left: 3vw;
}
#hero {
background-image: url(../../images/banner_background.jpg);
background-repeat: no-repeat;
background-size: cover;
background-position: top;
height: 95vh;
}
#hero #hero_overlay {
background-color: rgba(0, 0, 0, 0.4);
width: 100%;
height: 100%;
}
#hero .title, #hero .sub_title {
color: #FFFFFF;
text-align: center;
}
#hero .title {
font-size: 3.5rem;
}
/*# sourceMappingURL=main.css.map */
我还使用normalize.css进行了一些调整，以使跨浏览器的格式成为同义词：
* {
margin: 0;
padding: 0;
border: 0;
outline: 0;
font-size: 100%;
vertical-align: baseline;
background: transparent;
box-sizing: border-box;
}
/*! normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css */
/* Document
========================================================================== */
/**
* 1. Correct the line height in all browsers.
* 2. Prevent adjustments of font size after orientation changes in iOS.
*/
html {
line-height: 1.15; /* 1 */
-webkit-text-size-adjust: 100%; /* 2 */
padding: 0;
margin: 0;
}
/* Sections
========================================================================== */
/**
* Remove the margin in all browsers.
*/
body {
margin: 0;
padding: 0;
}
/**
* Render the `main` element consistently in IE.
*/
main {
display: block;
}
/**
* Correct the font size and margin on `h1` elements within `section` and
* `article` contexts in Chrome, Firefox, and Safari.
*/
h1 {
font-size: 2em;
margin: 0.67em 0;
}
/* Grouping content
========================================================================== */
/**
* 1. Add the correct box sizing in Firefox.
* 2. Show the overflow in Edge and IE.
*/
hr {
height: 0; /* 1 */
overflow: visible; /* 2 */
}
/**
* 1. Correct the inheritance and scaling of font size in all browsers.
* 2. Correct the odd `em` font sizing in all browsers.
*/
pre {
font-family: monospace, monospace; /* 1 */
font-size: 1em; /* 2 */
}
/* Text-level semantics
========================================================================== */
/**
* Remove the gray background on active links in IE 10.
*/
a {
background-color: transparent;
}
/**
* 1. Remove the bottom border in Chrome 57-
* 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
*/
abbr[title] {
border-bottom: none; /* 1 */
text-decoration: underline; /* 2 */
text-decoration: underline dotted; /* 2 */
}
/**
* Add the correct font weight in Chrome, Edge, and Safari.
*/
b,
strong {
font-weight: bolder;
}
/**
* 1. Correct the inheritance and scaling of font size in all browsers.
* 2. Correct the odd `em` font sizing in all browsers.
*/
code,
kbd,
samp {
font-family: monospace, monospace; /* 1 */
font-size: 1em; /* 2 */
}
/**
* Add the correct font size in all browsers.
*/
small {
font-size: 80%;
}
/**
* Prevent `sub` and `sup` elements from affecting the line height in
* all browsers.
*/
sub,
sup {
font-size: 75%;
line-height: 0;
position: relative;
vertical-align: baseline;
}
sub {
bottom: -0.25em;
}
sup {
top: -0.5em;
}
/* Embedded content
========================================================================== */
/**
* Remove the border on images inside links in IE 10.
*/
img {
border-style: none;
}
/* Forms
========================================================================== */
/**
* 1. Change the font styles in all browsers.
* 2. Remove the margin in Firefox and Safari.
*/
button,
input,
optgroup,
select,
textarea {
font-family: inherit; /* 1 */
font-size: 100%; /* 1 */
line-height: 1.15; /* 1 */
margin: 0; /* 2 */
}
/**
* Show the overflow in IE.
* 1. Show the overflow in Edge.
*/
button,
input { /* 1 */
overflow: visible;
}
/**
* Remove the inheritance of text transform in Edge, Firefox, and IE.
* 1. Remove the inheritance of text transform in Firefox.
*/
button,
select { /* 1 */
text-transform: none;
}
/**
* Correct the inability to style clickable types in iOS and Safari.
*/
button,
[type="button"],
[type="reset"],
[type="submit"] {
-webkit-appearance: button;
}
/**
* Remove the inner border and padding in Firefox.
*/
button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
border-style: none;
padding: 0;
}
/**
* Restore the focus styles unset by the previous rule.
*/
button:-moz-focusring,
[type="button"]:-moz-focusring,
[type="reset"]:-moz-focusring,
[type="submit"]:-moz-focusring {
outline: 1px dotted ButtonText;
}
/**
* Correct the padding in Firefox.
*/
fieldset {
padding: 0.35em 0.75em 0.625em;
}
/**
* 1. Correct the text wrapping in Edge and IE.
* 2. Correct the color inheritance from `fieldset` elements in IE.
* 3. Remove the padding so developers are not caught out when they zero out
* `fieldset` elements in all browsers.
*/
legend {
box-sizing: border-box; /* 1 */
color: inherit; /* 2 */
display: table; /* 1 */
max-width: 100%; /* 1 */
padding: 0; /* 3 */
white-space: normal; /* 1 */
}
/**
* Add the correct vertical alignment in Chrome, Firefox, and Opera.
*/
progress {
vertical-align: baseline;
}
/**
* Remove the default vertical scrollbar in IE 10+.
*/
textarea {
overflow: auto;
}
/**
* 1. Add the correct box sizing in IE 10.
* 2. Remove the padding in IE 10.
*/
[type="checkbox"],
[type="radio"] {
box-sizing: border-box; /* 1 */
padding: 0; /* 2 */
}
/**
* Correct the cursor style of increment and decrement buttons in Chrome.
*/
[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
height: auto;
}
/**
* 1. Correct the odd appearance in Chrome and Safari.
* 2. Correct the outline style in Safari.
*/
[type="search"] {
-webkit-appearance: textfield; /* 1 */
outline-offset: -2px; /* 2 */
}
/**
* Remove the inner padding in Chrome and Safari on macOS.
*/
[type="search"]::-webkit-search-decoration {
-webkit-appearance: none;
}
/**
* 1. Correct the inability to style clickable types in iOS and Safari.
* 2. Change font properties to `inherit` in Safari.
*/
::-webkit-file-upload-button {
-webkit-appearance: button; /* 1 */
font: inherit; /* 2 */
}
/* Interactive
========================================================================== */
/*
* Add the correct display in Edge, IE 10+, and Firefox.
*/
details {
display: block;
}
/*
* Add the correct display in all browsers.
*/
summary {
display: list-item;
}
/* Misc
========================================================================== */
/**
* Add the correct display in IE 10+.
*/
template {
display: none;
}
/**
* Add the correct display in IE 10.
*/
[hidden] {
display: none;
}
答案 0 :(得分：3)
它是由margin collapsing现象引起的。参见related question。如果删除 main.css 的内容，您会看到布局变为“正常”（例如，顶部没有空格），因此 normalize.css 并非导致问题。
如何解决？
只需将其添加到您的 normalize.css * {}部分。参见fiddle。
* {
overflow:hidden; /* or auto */
}
答案 1 :(得分：1)
尝试添加此内容：
body {
margin: 0;
}
#hero .title {
margin-top: 0;
}
您的body和.title的样式如下：
body {
font-family: "Brandon Grotesque", Helvetica, sans-serif;
margin: 0;
}
#hero .title {
margin-top: 0;
font-size: 3.5rem;
}