-
-
- 設置最終形狀參數:
- 設置長半軸和短半軸
- 設置橢圓對稱中心
- 設置色標
- 輸出代碼:
radial-gradient(circle closest-side at center, red 50%, blue 100%,white 100%)
- 設置最終形狀參數:
徑向漸變(radial gradients):從起點到終點顏色從內而外沿進行圓形漸變。
語法
background:radial-gradient(center,shape size,start-color,……,last-color);
徑向漸變-設置形狀
語法:
background:radial-gradient(shape,start-color,……,last-color);
說明:
shape值可以取兩個
circle——圓形
ellipse——橢圓(默認)
徑向漸變-尺寸大小關鍵字
尺寸大小關鍵字是確定結束顏色的位置,默認值為farthest-corner。
語法
background:radial-gradient(size,start-color,……,last-color);
size取值為以下四個關鍵字:
closest-side:最近邊
farthest-side:最遠邊
closest-corner:最近角
farthest-corner:最遠角
實例:
div { width: 300px; height: 200px; /* Safari 5.1 - 6.0 */ background: -webkit-radial-gradient(30% 70%, farthest-side, blue, green, yellow, black); /* Opera 11.6 - 12.0 */ background: -o-radial-gradient(30% 70%, farthest-side, blue, green, yellow, black); /* Firefox 3.6 - 15 */ background: -moz-radial-gradient(30% 70%, farthest-side, blue, green, yellow, black); /* 標准的語法 */ background: radial-gradient(30% 70%, farthest-side, blue, green, yellow, black); }
徑向漸變-圓心位置
語法:
background:radial-gradient(level-percent vertical-percent,start-color,……,last-color);
注意:圓心位置的標准語法目前主流瀏覽器支持性較差,需要注意加瀏覽器前綴。
一般使用時的方式:
-webkit-background:radial-gradient(level-percent vertical-percent,start-color,……,last-color);
-o-background:radial-gradient(level-percent vertical-percent,start-color,……,last-color);
-moz-background:radial-gradient(level-percent vertical-percent,start-color,……,last-color);
background:radial-gradient(level-percent vertical-percent,start-color,……,last-color);
思考:1、漸變中顏色后面百分比值有何含義?
3-12編程練習
小伙伴們,學習了CSS3徑向漸變,根據效果圖,補充代碼,實現:
(1)以中心(60% 40%)為起點,設置圓心到最近邊、最圓邊、最近角、最圓角的四種徑向漸變效果。
(2)徑向漸變的形狀是圓形
(3)顏色由里到外分別是紅、黃、綠、藍
效果圖如下
任務
給4個元素分別設置背景顏色徑向漸變
(1)分別設置徑向漸變大小為最近邊、最遠邊、最近角、最遠角
(2)漸變的圓心為60%和40%
(3)漸變的形狀為圓形
(4)漸變的顏色由里到外依次為紅、黃、綠、藍。
參考代碼:
<!DOCTYPE html> <html> <head lang="zh-CN"> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no"> <title>徑向漸變</title> <style> div { width: 200px; height: 300px; float: left; margin: 100px 0 0 100px; } /* 補充代碼,分別寫出4個元素的背景漸變效果 */ .div1 { background: -webkit-radial-gradient(60% 40%,closest-side circle, red,yellow,green,blue); /* Opera 11.6 - 12.0 */ background: -o-radial-gradient(60% 40%,closest-side circle, red,yellow,green,blue); /* Firefox 3.6 - 15 */ background: -moz-radial-gradient(60% 40%,closest-side circle, red,yellow,green,blue); /* 標准的語法 */ background: radial-gradient(60% 40%,closest-side circle, red,yellow,green,blue); } .div2 { background: -webkit-radial-gradient(60% 40%,farthest-side circle, red,yellow,green,blue); /* Opera 11.6 - 12.0 */ background: -o-radial-gradient(60% 40%,farthest-side circle, red,yellow,green,blue); /* Firefox 3.6 - 15 */ background: -moz-radial-gradient(60% 40%,farthest-side circle, red,yellow,green,blue); /* 標准的語法 */ background: radial-gradient(60% 40%,farthest-side circle, red,yellow,green,blue); } .div3 { background: -webkit-radial-gradient(60% 40%,closest-corner circle, red,yellow,green,blue); /* Opera 11.6 - 12.0 */ background: -o-radial-gradient(60% 40%,closest-corner circle, red,yellow,green,blue); /* Firefox 3.6 - 15 */ background: -moz-radial-gradient(60% 40%,closest-corner circle, red,yellow,green,blue); /* 標准的語法 */ background: radial-gradient(60% 40%,closest-corner circle, red,yellow,green,blue); } .div4 { background: -webkit-radial-gradient(60% 40%,farthest-corner circle, red,yellow,green,blue); /* Opera 11.6 - 12.0 */ background: -o-radial-gradient(60% 40%,farthest-corner circle, red,yellow,green,blue); /* Firefox 3.6 - 15 */ background: -moz-radial-gradient(60% 40%,farthest-corner circle, red,yellow,green,blue); /* 標准的語法 */ background: radial-gradient(60% 40%,farthest-corner circle, red,yellow,green,blue); } </style> </head> <body> <div class="div1"></div> <div class='div2'></div> <div class='div3'></div> <div class='div4'></div> </body> </html>
徑向漸漸-重復漸變
background:repeating-radial-gradient(color1 length|percent,color2 length|percent,……);
3-14編程練習
小伙伴們,我們學習了CSS3徑向漸變中的重復漸變,接下來,根據效果圖寫出代碼,實現以元素中心為原點進行多個彩虹球的重復徑向漸變。
(1)要求彩虹的7個顏色,取值范圍從0%開始,一次加5%,比如紅色是0%,橙色是5%,黃色是10%,依次類推
(2)提示:彩虹球的顏色,用英語單詞表示即可
(3)效果圖如下:
參考代碼:
<!DOCTYPE html> <html> <head lang="zh-CN"> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no"> <title>徑向漸變</title> <style> div { width: 400px; height: 400px; /* 補充代碼 */ background: -webkit-repeating-radial-gradient(closest-side circle, red 0%,orange 5%,yellow 10%,green 15%,blue 20%,indigo 25%,purple 30%); /* Opera 11.6 - 12.0 */ background: -o-repeating-radial-gradient( closest-side circle,red 0%,orange 5%,yellow 10%,green 15%,blue 20%,indigo 25%,purple 30%); /* Firefox 3.6 - 15 */ background: -moz-repeating-radial-gradient(closest-side circle,red 0%,orange 5%,yellow 10%,green 15%,blue 20%,indigo 25%,purple 30%); /* 標准的語法 */ background: repeating-radial-gradient( closest-side circle, red 0%,orange 5%,yellow 10%,green 15%,blue 20%,indigo 25%,purple 30%); } </style> </head> <body> <div class="div1"></div> </body> </html>
3-18編程練習
小伙伴們,根據要求,補充代碼(使用CSS3背景的漸變及其它屬性寫出),要求如下:
四個角是紫色,中間的顏色是黃色
將上面的小圖呈4*4顯示出來,效果如下:
任務
第一步:使用線性漸變創建背景圖片
(1)先將單個的背景效果寫出來
(2)這個漸變效果是四個角是紫色,中間是透明的,可以使用角度漸變寫出來
第二步:規定這個背景圖像的尺寸是100*100.
參考代碼:
<!DOCTYPE html> <html> <head lang="zh-CN"> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no"> <title>3-18編程練習</title> <style> div { width: 400px; height: 400px; background-color: yellow; /* 補充代碼 */ background-size: 100px 100px; background-image: -webkit-linear-gradient(45deg, purple 25%, transparent 25%), -webkit-linear-gradient(45deg, transparent 75%, purple 75%), -webkit-linear-gradient(-45deg, purple 25%, transparent 25%), -webkit-linear-gradient(-45deg, transparent 75%, purple 75%); /* Opera 11.6 - 12.0 */ background-image: -o-linear-gradient(45deg, purple 25%, transparent 25%), -o-linear-gradient(45deg, transparent 75%, purple 75%), -o-linear-gradient(-45deg, purple 25%, transparent 25%), -o-linear-gradient(-45deg, transparent 75%, purple 75%); /* Firefox 3.6 - 15 */ background-image: -moz-linear-gradient(45deg, purple 25%, transparent 25%), -moz-linear-gradient(45deg, transparent 75%, purple 75%), -moz-linear-gradient(-45deg, purple 25%, transparent 25%), -moz-linear-gradient(-45deg, transparent 75%, purple 75%); /* 標准的語法 */ background-image: linear-gradient(45deg, purple 25%, transparent 25%), linear-gradient(45deg, transparent 75%, purple 75%), linear-gradient(-45deg, purple 25%, transparent 25%), linear-gradient(-45deg, transparent 75%, purple 75%); } </style> </head> <body> <div class="div1"></div> </body> </html>