🔍 CSS Attribute Selectors & Media Types

/* Select elements with specific attribute */
a[target] {
    background: yellow;
}

input[required] {
    border-left: 3px solid red;
}

img[alt] {
    border: 2px solid green;
}

/* Exact value match */
input[type="text"] {
    border: 1px solid blue;
}

a[target="_blank"] {
    color: red;
}

button[type="submit"] {
    background: green;
    color: white;
}

/* Starts with value */
a[href^="https"] {
    color: green;
    font-weight: bold;
}

a[href^="http://"] {
    color: blue;
}

a[href^="mailto:"] {
    color: orange;
}

/* Class names starting with btn- */
[class^="btn-"] {
    padding: 10px 20px;
    border-radius: 5px;
}

/* Ends with value */
a[href$=".pdf"] {
    color: red;
    font-weight: bold;
}

a[href$=".pdf"]::after {
    content: " 📄";
}

a[href$=".zip"]::after {
    content: " 📦";
}

img[src$=".jpg"],
img[src$=".png"] {
    border: 2px solid gray;
}

/* Contains value anywhere */
a[href*="google"] {
    color: #4285f4;
}

a[href*="github"] {
    color: #333;
}

[class*="icon"] {
    display: inline-block;
    width: 20px;
    height: 20px;
}

input[name*="email"] {
    background: url('email-icon.png') no-repeat right;
}

/* Matches space-separated word */
[class~="button"] {
    padding: 10px 20px;
}

/* Works with multiple classes */
/* class="primary button large" */
[class~="button"] {
    /* Matches */
}

/* Matches exact value or value- */
[lang|="en"] {
    color: blue;
}

/* Matches: lang="en" or lang="en-US" or lang="en-GB" */

/* Case-insensitive matching */
a[href$=".PDF" i] {
    color: red;
}

/* Matches: .pdf, .PDF, .Pdf, .pDF, etc. */

input[type="email" i] {
    border-color: blue;
}

/* Select by data attributes */
[data-status="active"] {
    background: green;
    color: white;
}

[data-status="pending"] {
    background: orange;
    color: white;
}

[data-status="inactive"] {
    background: gray;
    color: white;
}

/* Use in tooltips */
[data-tooltip] {
    position: relative;
    cursor: help;
}

[data-tooltip]::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    padding: 8px 12px;
    background: #333;
    color: white;
    border-radius: 4px;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}

[data-tooltip]:hover::after {
    opacity: 1;
}

/* Style external links differently */
a[href^="http"]::after {
    content: " ↗";
    font-size: 0.8em;
}

/* Internal links (no icon) */
a[href^="/"],
a[href^="#"] {
    /* No icon */
}

/* Add icons based on file type */
a[href$=".pdf"]::before {
    content: "📄 ";
}

a[href$=".doc"]::before,
a[href$=".docx"]::before {
    content: "📝 ";
}

a[href$=".zip"]::before {
    content: "📦 ";
}

a[href$=".mp3"]::before,
a[href$=".wav"]::before {
    content: "🎵 ";
}

/* Style required inputs */
input[required] {
    border-left: 3px solid #e74c3c;
}

/* Add asterisk to required labels */
label[for] input[required] ~ label::after,
input[required] + label::after {
    content: " *";
    color: red;
    font-weight: bold;
}

/* Different button types */
button[type="submit"] {
    background: #27ae60;
    color: white;
}

button[type="reset"] {
    background: #e74c3c;
    color: white;
}

button[disabled] {
    background: #95a5a6;
    cursor: not-allowed;
    opacity: 0.6;
}

/* Basic media query */
@media screen and (max-width: 768px) {
    /* Styles for screens 768px and smaller */
    .container {
        width: 100%;
        padding: 10px;
    }
}

/* Mobile First Approach */

/* Extra Small (phones, less than 576px) */
/* Default styles go here */

/* Small devices (landscape phones, 576px and up) */
@media (min-width: 576px) {
    .container { max-width: 540px; }
}

/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
    .container { max-width: 720px; }
}

/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {
    .container { max-width: 960px; }
}

/* Extra large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {
    .container { max-width: 1140px; }
}

/* Desktop styles by default */

/* Tablet (max 1024px) */
@media (max-width: 1024px) {
    .sidebar { width: 200px; }
}

/* Mobile (max 768px) */
@media (max-width: 768px) {
    .sidebar { 
        width: 100%;
        position: static;
    }
}

/* Small mobile (max 480px) */
@media (max-width: 480px) {
    .container { padding: 10px; }
}

/* Width queries */
@media (min-width: 600px) { }
@media (max-width: 1200px) { }
@media (width: 800px) { }

/* Height queries */
@media (min-height: 600px) { }
@media (max-height: 800px) { }

/* Portrait (height > width) */
@media (orientation: portrait) {
    .gallery {
        grid-template-columns: 1fr;
    }
}

/* Landscape (width > height) */
@media (orientation: landscape) {
    .gallery {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Specific aspect ratio */
@media (aspect-ratio: 16/9) {
    .video { width: 100%; }
}

/* Minimum aspect ratio */
@media (min-aspect-ratio: 16/9) {
    /* Wide screens */
}

/* High-resolution displays (Retina) */
@media (min-resolution: 2dppx) {
    .logo {
        background-image: url('logo@2x.png');
        background-size: 100px 50px;
    }
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
    body {
        background: #1a1a1a;
        color: #ffffff;
    }
}

/* Light mode */
@media (prefers-color-scheme: light) {
    body {
        background: #ffffff;
        color: #000000;
    }
}

/* Respect user's motion preferences */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Screen (default) */
@media screen {
    body { font-family: sans-serif; }
}

/* Print */
@media print {
    header, footer, nav {
        display: none;
    }
    
    body {
        font-size: 12pt;
        color: black;
    }
    
    a::after {
        content: " (" attr(href) ")";
    }
}

/* All media types */
@media all {
    /* Applies to everything */
}

/* AND operator */
@media screen and (min-width: 768px) and (max-width: 1024px) {
    /* Tablets only */
}

/* OR operator (comma) */
@media (max-width: 768px), (orientation: portrait) {
    /* Mobile OR portrait */
}

/* NOT operator */
@media not print {
    /* Everything except print */
}

/* Complex combination */
@media screen and (min-width: 768px) and (orientation: landscape) {
    /* Landscape tablets and desktops */
}

/* Desktop navigation */
nav {
    display: flex;
    justify-content: space-between;
}

/* Mobile navigation */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .nav-menu {
        display: none;
    }
    
    .nav-menu.active {
        display: flex;
        flex-direction: column;
    }
}

/* Desktop: 4 columns */
.grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

/* Tablet: 2 columns */
@media (max-width: 1024px) {
    .grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Mobile: 1 column */
@media (max-width: 768px) {
    .grid {
        grid-template-columns: 1fr;
    }
}

/* Base font sizes */
h1 { font-size: 3rem; }
h2 { font-size: 2.5rem; }
p { font-size: 1rem; }

/* Tablet adjustments */
@media (max-width: 1024px) {
    h1 { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
}

/* Mobile adjustments */
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    p { font-size: 0.95rem; }
}