Ni nini aina kuu za CSS selectors?

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Wachanganuzi hutekeleza ni elementi ipi ambayo kanuni inatumika. Zinatoka rahisi (kwa tagi) hadi kwa wachanganuzi wenye nguvu. ```css /* Basic selectors */ p { } /* type: all

*/ .card { } /* class: elements with class="card" (reusable) */ #header { } /* id: the one element with id="header" (unique) */ * { } /* universal: every element */ [type="text"]{ } /* attribute: inputs with type=text */ ``` ## Wachanganuzi — mahusiano kati ya elementi ```css .menu li { } /* descendant: any li INSIDE .menu (any depth) */ .menu > li { } /* child: only DIRECT children li */ h2 + p { } /* adjacent sibling: the p immediately AFTER an h2 */ h2 ~ p { } /* general sibling: all p siblings after an h2 */ ``` Tofauti kati ya nafasi (descendant) na `>` (mtoto wa moja kwa moja) ni muhimu: `.menu li` inafanana pia na `li` zilizobadilishwa kwa kina, wakati `.menu > li` inafanana na kiwango cha juu tu. ## Pseudo-classes na pseudo-elements ```css a:hover { } /* state: while hovered */ li:first-child { } /* structural: the first li */ li:nth-child(2n){ } /* every even li */ p::first-line { } /* pseudo-element: the first rendered line */ ``` ## Kuunganisha na wachanganuzi wa kisasa ```css h1, h2, h3 { } /* apply to all three */ :is(h1, h2) a { } /* :is() shortens long selector lists */ .card:has(img) { } /* :has() — a parent that CONTAINS an img */ ``` ## Kwa nini inahitaji Wachanganuzi ni jinsi unavyounganisha mitindo na markup. Kupata ustadi wa madarasa (mfanyakazi mkuu), wachanganuzi (kwa mahusiano), na pseudo-classes ya miundo/hali hukuruhusu kutekeleza kwa usahihi bila kuongeza madarasa ya ziada mahali penye — na `:is()`/`:has()` za kisasa hufanya utekelezaji wenye changamoto kuwa mfupi. Penda madarasa badala ya ids/uingizaji uzani wa juu kuweka specificity inayoweza kusimamia.