在html中，即使我們沒有指定頁面元素顯示的css樣式，元素也會按照默認的的標準css樣式去顯示。因此掌握基本的html標簽可以在一定程度上精簡你的css代碼，現將html標簽的默認屬性進行一定的匯總如下：

li              { display: list-item } 
head            { display: none } 
table           { display: table } 
tr              { display: table-row } 
thead           { display: table-header-group } 
tbody           { display: table-row-group } 
tfoot           { display: table-footer-group } 
col             { display: table-column } 
colgroup        { display: table-column-group } 
td, th          { display: table-cell; } 
caption         { display: table-caption } 
th              { font-weight: bolder; text-align: center } 
caption         { text-align: center } 
body            { margin: 8px; line-height: 1.12 }

html, address,
blockquote,
body, dd, div,
dl, dt, fieldset, form,
frame, frameset,
h1, h2, h3, h4,
h5, h6, noframes,
ol, p, ul, center,
dir, hr, menu, pre   { display: block }

h4, p,
blockquote, ul,
fieldset, form,
ol, dl, dir,
menu            { margin: 1.12em 0 }

h1              { font-size: 2em; margin: .67em 0 } 
h2              { font-size: 1.5em; margin: .75em 0 } 
h3              { font-size: 1.17em; margin: .83em 0 } 
h5              { font-size: .83em; margin: 1.5em 0 } 
h6              { font-size: .75em; margin: 1.67em 0 } 
h1, h2, h3, h4,
h5, h6, b,
strong          { font-weight: bolder } 
blockquote      { margin-left: 40px; margin-right: 40px } 
i, cite, em, var, address    { font-style: italic } 
pre, tt, code, kbd, samp     { font-family: monospace } 
pre             { white-space: pre } 
button, textarea, input, object, select          { display:inline-block; } 
big             { font-size: 1.17em } 
small, sub, sup { font-size: .83em } 
sub             { vertical-align: sub } 
sup             { vertical-align: super } 
table           { border-spacing: 2px; } 
thead, tbody, tfoot           { vertical-align: middle } 
td, th          { vertical-align: inherit } 
s, strike, del  { text-decoration: line-through } 
hr              { border: 1px inset } 
ol, ul, dir, menu, dd        { margin-left: 40px } 
ol              { list-style-type: decimal } 
ol ul, ul ol, ul ul, ol ol    { margin-top: 0; margin-bottom: 0 } 
u, ins          { text-decoration: underline } 
br:before       { content: "/A" } 
:before, :after { white-space: pre-line } 
 
center          { text-align: center } 
abbr, acronym   { font-variant: small-caps; letter-spacing: 0.1em } 
:link, :visited { text-decoration: underline } 
:focus          { outline: thin dotted invert } 
   
@media print { 
  h1            { page-break-before: always } 
  h1, h2, h3,
  h4, h5, h6    { page-break-after: avoid } 
  ul, ol, dl    { page-break-before: avoid }
}

BDO[DIR="ltr"]  { direction: ltr; unicode-bidi: bidi-override } 
BDO[DIR="rtl"]  { direction: rtl; unicode-bidi: bidi-override } 
 
*[DIR="ltr"]    { direction: ltr; unicode-bidi: embed } 
*[DIR="rtl"]    { direction: rtl; unicode-bidi: embed } 

當我們預想的css樣式和默認樣式一致時，我們就不必浪費不必要的css代碼在那些頁面元素上了，從而達到css代碼的精簡！