1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
|
Network Working Group H. Lie
Request for Comments: 2318 B. Bos
Category: Informational C. Lilley
W3C
March 1998
The text/css Media Type
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Abstract
Cascading Style Sheets (CSS) is a style sheet language for the World
Wide Web. CSS style sheets have been in use since October 1995 using
the Media Type text/css without registration; this memo seeks to
regularize that position.
1. Introduction
The World Wide Web Consortium has issued a Recommendation [1], which
defines Cascading Style Sheets, level 1. This memo provides
information about the text/css Media Type.
2. Cascading Style Sheets
Cascading Style Sheets (CSS) is a style sheet language for the World
Wide Web. It describes the presentation (e.g. fonts, colors and
spacing) of structured documents. CSS is human readable and writable,
and expresses style in common desktop publishing terminology.
CSS style sheets have been in use since October 1995 using the Media
Type text/css without registration; this memo seeks to regularize
that position.
A CSS style sheet can be either:
Lie, et. al. Informational [Page 1]
RFC 2318 text/css Media Type March 1998
(1) external - the style sheet is linked to a document through a
URI and exists as a separate object on the Web. The media type
text/css is used when fetching the object, for example in the
Content-Type and Accept header fields of HTTP [2].
(2) internal - the style sheet is contained within the document. A
typical scenario is an HTML [3] document that contains a style
sheet within the STYLE element. Due to this close relationship,
HTML and CSS share the same top-level name ("text").
4. Registration Information
To: ietf-types@iana.org
Subject: Registration of MIME media type text/css
MIME media type name: text
MIME subtype name: css
Required parameters: none
Optional parameters: charset
The syntax of CSS is expressed in US-ASCII, but a CSS file can
contain strings which may use any Unicode character. Any charset
that is a superset of US-ASCII may be used; US-ASCII, iso-8859-X
and utf-8 are recommended.
Encoding considerations:
For use with transports that are not 8-bit clean, quoted-
printable encoding is recommended since the majority of
characters will be CSS syntax and thus US-ASCII
Security considerations:
Applying a style sheet to a document may hide information
otherwise visible. For example, a very small font size may be
specified, or the display of certain document elements may be
turned off.
CSS style sheets consist of declarative property/value pairs
assigned to element selectors. They contain no executable code.
As with HTML documents, CSS style sheets may contain links to
other media (images, sounds, fonts, other style sheets) and those
links are typically followed automatically by software, resulting
Lie, et. al. Informational [Page 2]
RFC 2318 text/css Media Type March 1998
in the transfer of files without the explicit request of the user
for each one. The security considerations of each linked file are
those of the individual registered types.
Interoperability considerations:
CSS has proven to be widely interoperable across computer
platforms, across Web browsers of different makes, and for import
and export in multiple authoring tools.
Published specification: see [1]
Applications which use this media type:
CSS is device-, platform- and vendor-neutral and is supported by
a wide range of Web user agents and authoring tools for
formatting HTML and XML documents.
Additional information:
Magic number(s): none
File extension(s): .css
Macintosh File Type Code(s): "css "
Object Identifier(s) or OID(s): none
Person & email address to contact for further information:
The authors of this memo.
Intended usage: COMMON
Author/Change controller:
5. References
[1] Lie, H., and B. Bos, "Cascading Style Sheets, level 1",
W3C Recommendation REC-CSS1-961217, http://www.w3.org/TR/REC-
CSS1-961217, December 1996.
[2] Fielding, R., Gettys, J., Mogul, J., Nielsen, H., and T.
Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC
2068, January 1997.
[3] Raggett, D., Le Hors, A. and I. Jacobs, "HTML 4.0
Specification", W3C Recommendation REC-html40-971218,
http://www.w3.org/TR/REC-html40, December 1997.
Lie, et. al. Informational [Page 3]
RFC 2318 text/css Media Type March 1998
6. Authors' Addresses
Hakon Lie
W3C/INRIA
2004, route des Lucioles - B.P. 93
06902 Sophia Antipolis Cedex
FRANCE
Phone: +33 (0)492387771
Fax: +33 (0)493657765
EMail: howcome@w3.org
Bert Bos
2004, route des Lucioles - B.P. 93
06902 Sophia Antipolis Cedex
FRANCE
Phone: +33 (0)492387692
Fax: +33 (0)493657765
EMail: bert@w3.org
Chris Lilley
2004, route des Lucioles - B.P. 93
06902 Sophia Antipolis Cedex
FRANCE
Phone: +33 (0)492387987
Fax: +33 (0)493657765
EMail: chris@w3.org
Lie, et. al. Informational [Page 4]
RFC 2318 text/css Media Type March 1998
7. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implmentation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE."
Lie, et. al. Informational [Page 5]
|
