CSS tom qab transparency. Pob tshab tom qab lossis cov ntawv luam nrog CSS

Nrog lub advent ntawm CSS3 web designers ua hauj lwm nyob rau hauv ntau txoj kev uas tau ua yooj yim dua thiab ntau zajlus kom: tom qab tag nrho, koj muaj peev xwm tam sim no yeej flexibly customize ib yam khoom, tsawg zaus resorting rau JavaScript. Wb hais tias koj yuav tsum tau kho cov transparency ntawm lub keeb kwm yav dhau - CSS sai li sai tau muaj ob peb yam kev xaiv.

Tom qab tau hais tseg los ntawm ib tug txheej ntawm cwj pwm (tom qab duab, tom qab-txoj hauj lwm , tom qab-loj, me, tom qab rov, tom qab-txuas, tom qab-paus chiv keeb, tom qab-clip, tom qab-xim), txhua tus uas yuav tsum tau muab cais los yog ua ke nyob rau hauv lub attribute tom qab. Cia peb kawm txhua yam ntawm lawv nyob rau hauv kom meej.

Tus cwj pwm tom qab-xim

Nyob rau hauv CSS, xim tom qab yuav tsum teev nyob rau hauv ob peb txoj kev: siv ib tug hex code, xim lub npe los yog RGB-nkag. Nyob rau hauv CSS3 nws los ua tau siv es tsis txhob ntawm RGB-cov ntaubntawv povthawj siv kev xaiv uas muaj RGBA.

Hex xim code yog kaw nyob rau hauv cov cuab yeej tom qab lub ntxaij ntoo: tom qab-xim: # FFDAB9. Yog hais tias cov cim nyob rau hauv no nkag yog tib yam officers, lub code yog feem ntau ib tug me ntsis txiav: # ccff00 yuav sau raws li # cf0:

lub cev {tom qab-xim: # cf0 ;}.

Lub npe yog, txawm nyob rau hauv lub feem ntau txawv xim. Piv txwv li, nyob rau hauv tas li ntawd mus rau tus txheej txheem liab thiab dawb koj yuav siv NavajoWhite (#FFDEAD) los yog Honeydew2 (# E0EEE0):

lub cev {tom qab-xim: ntshav; }.

Cov yav tas kev xaiv no yog RGB los yog RGBA nkag tso cai rau koj kom meej tsis tau tsuas yog cov xim tab sis kuj lub transparency ntawm lub CSS tom qab, tab sis txoj kev ua hauj lwm nkaus xwb nyob rau hauv IE versions laus tshaj 9. Lwm yam browsers paub txog tej version nrog transparency. Raws li cov W3C qauv nws yog preferable siv tseem RGBA es tsis txhob ntawm qhov ntau li ib txwm RGB.

Qhov kawg tus nqi nyob rau hauv RGBA tom qab thiab teev lub opacity ntawm 0 (pob tshab) mus rau 1 (opaque).

Muaj ib co txawv txawv qhov tseem ceeb. Xim tom qab tau muab teev siv cov HSL thiab HSLA. Ob leeg ntxiv rau CSS3, thiab yog li ntawd yuav tsis txaus siab los ntawm IE version 9 los yog ntau dua. Embodiments tib yam RGB los yog RGBA, tsuas nyob rau hauv ib tug txawv hom: Hawj txawm (ntxoov ntxoo - tus nqi ntawm cov xim log, yog muab nyob rau hauv degrees), ntub txaus (saturation - xim siv raws li ib tug feem pua, ntawm 0 mus 100), ci (lightness - brightness, ntsuas zoo parameter ntub txaus ).

Tus cwj pwm tom qab duab

Qhov tseem ntoo khaub lig-browser version ntawm lub pob tshab tom qab - qhov no yog qhov kev siv ntawm daim duab. Nyob rau hauv CSS3, koj yuav teev ntau heev tshaj dua dluab, qhov no yog ua los ntawm ib tug tsis nco qab. Piv txwv li:

{Tom qab lub cev duab: url (bg1.png), url (bg2.png)}.

Qhov no txoj kev txhawb txawm IE8. Ob peb dluab nyob rau hauv lub keeb kwm yav dhau ntawm cov roj hmab siv nyob rau hauv lub layout. Ceeb tshaj, tsis txhob hnov qab siv tej yam duab thiab muab lub keeb kwm yav dhau xim nyob rau hauv CSS, raws li cov neeg siv yuav tsuas upload ib cov duab.

Tus cwj pwm tom qab-txoj hauj lwm

Yog hais tias koj siv ntawm daim duab mus teev tom qab tsev, CSS tso cai rau koj mus position cov duab nyob qhov twg ntawm qhov screen. Yog lub neej ntawd, cov duab nyob rau hauv lub Upper sab laug ces kaum. Tus Cwj Pwm yuav siv sij hawm yog hais lus qhia (sab saum toj, hauv qab, sab laug, txoj cai), ib tug hais txog zauv (txaus siab, pixels thiab lwm yam units). Nyob rau hauv cov ntaub ntawv no, koj yuav tsum qhia kom meej ob qhov tseem ceeb, kab rov tav thiab ntsug:

lub cev {tom qab-txoj hauj lwm: txoj cai center ;} - nyob rau hauv qhov kev piv txwv, cov qauv yuav tsum tau nyob rau sab xis ntawm cov nplooj ntawv, rau sab saum toj thiab hauv qab ntawm cov duab deb li cas los tau tib yam.

Tus cwj pwm tom qab-loj

Tej zaum nws yog tsim nyog los ncab lub CSS tom qab los yog txo nws loj. Ua li no, siv cov attribute tom qab-loj, me, thiab qhov loj ntawm lub keeb kwm yav dhau yuav teev nyob rau hauv pixels los yog feem pua, thiab lwm yam units.

Nrog rau qhov no attribute, muaj ib co teeb meem: kev tseeb zaub ntawm ib tug tom qab nyob rau hauv lub ua ntej lawm versions ntawm qhov browser tsiaj ntawv ua pib yuav tsum tau siv. Ntawm cov hoob kawm, tus tam sim no version tag nrho cov kev pab txhawb tus cwj pwm thiab xav tau kev muaj zog zoo.

Tus cwj pwm tom qab-Symptoms

Qhov no attribute qhia txog tus cwj pwm ntawm cov keeb kwm yav dhau dluab thaum scrolling. Yog li ntawd, nws yuav siv sij hawm 3 qhov tseem ceeb (tsis xws li cov inherit, tag nrho cov rau tag nrho cov cwj pwm sib tham nyob rau hauv no tsab xov xwm):

• taag - ua daim duab nyob rau tom qab ntawm tsau;
• scroll - tom qab phau nrog rau tus so ntawm lub ntsiab;
• hauv zos - cov duab nyob rau hauv keeb kwm yav dhau yog scrolled yog scrolling muaj cov ntsiab lus. Tom qab uas mus dhau tus txheem ntawm tus ncej tsau.

Piv txwv li ntawm kev siv:

lub cev {tom qab-Symptoms tsau}.

Tam sim no, Firefox tsis txhawb cov xeem vaj tse (lub zos).

Tus cwj pwm tom qab-paus chiv keeb

Qhov no attribute yog lub luag hauj lwm rau lub tso rau lub caij. Early browsers tsum tau siv cov tsiaj ntawv ua pib. Cov cuab yeej nws tus kheej muaj peb tsis:

• padding-box yog positioned txheeb ze rau ntawm ntug txawv, thaum noj mus rau hauv tus account lub thickness rau ntawm tus ncej;
• ciam teb kem zog sib txawv los ntawm lub yav dhau los nyob rau hauv uas tus ciam kab yuav ua tau kiag li los yog sib tshooj tus qauv;
• cov ntsiab lus-lub thawv tso duab pryavyazyvaya nws cov ntsiab lus.

Yog hais tias koj qhia kom meej ntau qhov tseem ceeb, ces browsers yuav hnov mob nyob rau hauv lawv tus kheej txoj kev: Firefox thiab Opera perceive tsuas yog thawj kev xaiv.

Tus cwj pwm tom qab rov

Raws li ib tug txoj cai, yog hais tias tus keeb kwm yav dhau duab teev, nws yuav tsum tau rov qab horizontally los mas. Rau qhov no thiab siv cov attribute tom qab rov. Yog li, thaiv tom qab, CSS uas muaj xws li ib tug vaj tse yuav muaj ib tug ntawm ob peb tsis:

• tsis muaj-rov - cov duab tshwm nyob rau hauv ib daim ntawv nyob rau hauv ib version;
• rov qab hais dua - tom qab yog rov qab rau hauv lub x thiab y;
• rov ua-x - tsuas yog horizontally;
• rov qab hais dua-y - tsuas yog mas;
• qhov chaw - tom qab yog rov qab rau, tab sis yog tias qhov chaw yog tsis yooj yim sua rau sau nyob rau hauv nruab nrab ntawm cov duab tshwm npliag;
• puag ncig - cov duab scaled, yog hais tias nws tsis sau tag nrho cov cheeb tsam ntawm tag nrho cov duab.

Piv txwv li ntawm tej cwj pwm:

lub cev {tom qab-rov tso: no- rov hais dua} - uas zoo sib xws keeb kwm yav dhau-rov tso: rov ua-y.

Nyob rau hauv CSS3 yuav qhia kom meej qhov tseem ceeb rau ntau cov dluab thaum qhia tsis, sib cais los ntawm commas.

Tus cwj pwm tom qab-clip

Qhov no attribute lub sij lub cwj pwm ntawm cov keeb kwm yav dhau nyob rau hauv ib thaj tsam (e.g., nyob rau hauv cov ntaub ntawv ntawm lub dotted ntas):

• padding-lub thawv - tom qab tso tawm kom pom nyob rau hauv sab hauv ntawm lub thaiv;
• ciam teb-lub thawv - cov duab los nyob rau hauv lub moj khaum;
• cov ntsiab lus-lub thawv - daim duab nyob rau tom qab yuav tsuas tshwm sim nyob rau hauv lub ntsiab lus.

Piv txwv li ntawm kev siv:

lub cev {tom qab-clip: content- box;}.

Chrom thiab Safari yuav tsum tau -webkit- prefix.

Opacity cwj pwm thiab lim

opacity attribute tso cai rau koj mus teem lub transparency ntawm lub keeb kwm yav dhau - CSS vaj tse yuav ua hauj lwm nyob rau hauv tag nrho cov browsers. Tus nqi yog teev nyob rau hauv cov kab los ntawm 0.0 mus 1.0 inclusive. Nyob rau hauv cov ntaub ntawv no, koj yuav tau teem lub transparency ntawm lub CSS tom qab tsis muaj integer nqi es tsis txhob ntawm 0.3 yog txaus sau .3:

.block {tom qab duab: url ( img.png); opacity: .3;}.

Yuav kom muab lub keeb kwm yav dhau opacity, CSS yog tsim txawm rau IE hauv qab no lub cuaj version, siv lub lim attribute:

.block {tom qab duab: url ( img.png); lim: alpha (opacity = 30)}.

Nyob rau hauv cov ntaub ntawv no, lub opacity tus nqi yog muab ntawm 0 thiab 100. Nco ntsoov tias lub opacity tus cwj pwm sib txawv transparency chaw ntawm RGBA qub txeeg qub teg: thaum uas siv cov opacity yuav ntshiab tsis tau tsuas yog lub keeb kwm yav dhau, tab sis tag nrho cov ntsiab hauv lub chav tsev.

Yuav saib xyuas koj pab txheeb cais rau CIS browsers thiab tag nrho lwm lub teb chaws. Qhov teeb meem biggest ntawm tag nrho cov DTP - laus versions of IE, lawv tsis pub koj mus siv lub twg tag CSS3. Nyob rau hauv layout tsis txhob hnov qab mus siv tshwj xeeb cov kev pab cuam uas xyuas seb koj tus browser txhawb tej CSS cov cuab yeej. Yog hais tias koj tsis tau nruab laus versions ntawm browsers, nrhiav cov kev pab uas yuav xyuas qhov chaw ua hauj lwm nyob rau hauv ntau yam browsers online.