/* Lesson 9: Responsive Web Design - Professional Styling */

/* Import Base Styles */
@import url('../assets/styles.css');

/* ==========================================================================
   Viewport Demo Styles
   ========================================================================== */

.viewport-demo {
    background: var(--color-surface);
    border-radius: 16px;
    padding: 2rem;
    border: 2px solid var(--color-border);
}

.viewport-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.viewport-example {
    background: var(--color-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.viewport-example h4 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
    text-align: center;
}

.device-mockup {
    background: #333;
    border-radius: 20px;
    padding: 20px;
    margin: 1rem auto;
    width: 200px;
    position: relative;
}

.device-mockup::before {
    content: '';
    position: absolute;
    top: 8px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: #666;
    border-radius: 2px;
}

.mockup-screen {
    background: white;
    border-radius: 8px;
    height: 280px;
    overflow: hidden;
    position: relative;
}

.mock-content {
    padding: 0.5rem;
    font-size: 0.7rem;
}

.mock-content.zoomed-out {
    transform: scale(0.4);
    transform-origin: top left;
    width: 250%;
}

.mock-content.responsive {
    /* Normal responsive layout */
}

.mock-header,
.mock-nav,
.mock-main,
.mock-sidebar {
    margin-bottom: 0.5rem;
    padding: 0.5rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
}

.mock-header {
    background: var(--color-primary);
    color: white;
}

.mock-nav {
    background: var(--color-secondary);
    color: white;
    font-size: 0.6rem;
}

.mock-main {
    background: var(--color-surface);
    height: 60px;
}

.mock-sidebar {
    background: var(--color-accent);
    color: white;
    font-size: 0.6rem;
}

.device-label {
    text-align: center;
    color: var(--color-text-light);
    font-size: 0.9rem;
    margin-top: 1rem;
}

.code-example {
    background: var(--color-code-bg);
    border-radius: 8px;
    padding: 1rem;
    margin-top: 1rem;
    border: 1px solid var(--color-border);
}

.code-example code {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.5;
    color: var(--color-text);
}

/* ==========================================================================
   Media Queries Playground
   ========================================================================== */

.media-queries-playground {
    background: var(--color-surface);
    border-radius: 16px;
    padding: 2rem;
    border: 2px solid var(--color-border);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.viewport-simulator {
    background: var(--color-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.device-selector {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.device-btn {
    padding: 0.5rem 1rem;
    background: var(--color-background);
    border: 2px solid var(--color-border);
    border-radius: 8px;
    color: var(--color-text);
    cursor: pointer;
    font-weight: 600;
    font-size: 0.85rem;
    transition: all 0.2s ease;
}

.device-btn:hover {
    background: var(--color-muted);
}

.device-btn.active {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.custom-width {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem;
    background: var(--color-muted);
    border-radius: 8px;
    min-width: 150px;
}

#width-slider {
    flex: 1;
    margin: 0;
}

#width-display {
    font-family: var(--font-mono);
    font-weight: 600;
    color: var(--color-primary);
    min-width: 60px;
    text-align: right;
}

.responsive-iframe-container {
    text-align: center;
    margin: 1.5rem 0;
}

#responsive-frame {
    width: 320px;
    height: 400px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    transition: width 0.3s ease;
    background: white;
}

.breakpoint-indicator {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
}

.breakpoint {
    flex: 1;
    text-align: center;
    padding: 0.75rem 0.5rem;
    background: var(--color-muted);
    border-radius: 6px;
    transition: all 0.3s ease;
    opacity: 0.6;
}

.breakpoint.active {
    background: var(--color-primary);
    color: white;
    opacity: 1;
    transform: translateY(-2px);
}

.bp-label {
    display: block;
    font-weight: 600;
    font-size: 0.9rem;
}

.bp-range {
    display: block;
    font-size: 0.75rem;
    opacity: 0.8;
}

.media-query-editor {
    background: var(--color-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.media-query-editor h4 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
}

.css-editor {
    position: relative;
}

#css-input {
    width: 100%;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.5;
    padding: 1rem;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-code-bg);
    color: var(--color-text);
    resize: vertical;
    min-height: 300px;
}

#css-input:focus {
    outline: none;
    border-color: var(--color-primary);
}

.apply-btn {
    background: var(--color-primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    margin-top: 1rem;
    transition: all 0.2s ease;
}

.apply-btn:hover {
    background: var(--color-secondary);
    transform: translateY(-1px);
}

/* ==========================================================================
   Responsive Patterns Showcase
   ========================================================================== */

.patterns-showcase {
    background: var(--color-surface);
    border-radius: 16px;
    overflow: hidden;
    border: 2px solid var(--color-border);
}

.pattern-tabs {
    display: flex;
    background: var(--color-card);
    border-bottom: 2px solid var(--color-border);
    overflow-x: auto;
}

.pattern-tab {
    padding: 1rem 1.5rem;
    background: none;
    border: none;
    color: var(--color-text-light);
    cursor: pointer;
    font-weight: 600;
    white-space: nowrap;
    transition: all 0.3s ease;
    position: relative;
}

.pattern-tab:hover {
    background: var(--color-muted);
    color: var(--color-text);
}

.pattern-tab.active {
    color: var(--color-primary);
    background: var(--color-background);
}

.pattern-tab.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--color-primary);
}

.pattern-demos {
    padding: 2rem;
}

.pattern-demo {
    display: none;
    animation: fadeIn 0.3s ease;
}

.pattern-demo.active {
    display: block;
}

.pattern-description {
    background: var(--color-card);
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 2rem;
    border: 1px solid var(--color-border);
}

.pattern-description h4 {
    margin: 0 0 0.5rem 0;
    color: var(--color-primary);
}

.pattern-description p {
    margin: 0;
    color: var(--color-text-light);
}

.pattern-visualization {
    background: var(--color-background);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    border: 1px solid var(--color-border);
}

.responsive-stages {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.stage {
    text-align: center;
}

.stage-label {
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.layout-preview {
    background: white;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    padding: 1rem;
    min-height: 120px;
}

/* Column Drop Pattern */
.desktop-layout .col {
    display: inline-block;
    width: 30%;
    margin: 0 1.5%;
    background: var(--color-secondary);
    color: white;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
    vertical-align: top;
}

.tablet-layout .col {
    display: inline-block;
    margin: 0 1% 0.5rem 1%;
    background: var(--color-secondary);
    color: white;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
    vertical-align: top;
}

.tablet-layout .col-1,
.tablet-layout .col-2 {
    width: 47%;
}

.tablet-layout .col-3.dropped {
    width: 98%;
    background: var(--color-accent);
}

.mobile-layout .col {
    display: block;
    width: 100%;
    margin: 0 0 0.5rem 0;
    background: var(--color-secondary);
    color: white;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
}

/* Mostly Fluid Pattern */
.fluid-container {
    display: grid;
    gap: 0.5rem;
    grid-template-columns: repeat(4, 1fr);
    max-width: 100%;
}

.fluid-container.tablet {
    max-width: 90%;
    margin: 0 auto;
}

.fluid-container.mobile {
    grid-template-columns: repeat(2, 1fr);
    max-width: 100%;
}

.fluid-col {
    background: var(--color-primary);
    color: white;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
    min-height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Layout Shifter Pattern */
.shifter-container.desktop {
    display: grid;
    grid-template-columns: 1fr 2fr 1fr;
    grid-template-rows: auto auto;
    gap: 0.5rem;
    grid-template-areas:
        "s1 s2 s3"
        "s4 s2 s3";
}

.shifter-container.tablet {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
    grid-template-areas:
        "s1 s2"
        "s3 s4";
}

.shifter-container.mobile {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.shifter-item {
    background: var(--color-accent);
    color: white;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
    min-height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.shifter-container.desktop .s1 { grid-area: s1; }
.shifter-container.desktop .s2 { grid-area: s2; }
.shifter-container.desktop .s3 { grid-area: s3; }
.shifter-container.desktop .s4 { grid-area: s4; }

.shifter-container.tablet .s1 { grid-area: s1; }
.shifter-container.tablet .s2 { grid-area: s2; }
.shifter-container.tablet .s3 { grid-area: s3; }
.shifter-container.tablet .s4 { grid-area: s4; }

/* Tiny Tweaks Pattern */
.tweaks-container {
    text-align: center;
    padding: 1rem;
}

.tweaks-container.desktop h3 {
    font-size: 1.5rem;
    margin: 1rem 0;
}

.tweaks-container.desktop .large-text {
    font-size: 1.1rem;
    line-height: 1.6;
    margin: 1.5rem 0;
}

.tweaks-container.desktop .btn-large {
    padding: 1rem 2rem;
    font-size: 1rem;
}

.tweaks-container.tablet h3 {
    font-size: 1.3rem;
    margin: 0.75rem 0;
}

.tweaks-container.tablet .medium-text {
    font-size: 1rem;
    line-height: 1.5;
    margin: 1rem 0;
}

.tweaks-container.tablet .btn-medium {
    padding: 0.75rem 1.5rem;
    font-size: 0.9rem;
}

.tweaks-container.mobile h3 {
    font-size: 1.1rem;
    margin: 0.5rem 0;
}

.tweaks-container.mobile .small-text {
    font-size: 0.9rem;
    line-height: 1.4;
    margin: 0.75rem 0;
}

.tweaks-container.mobile .btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.85rem;
}

.btn-large,
.btn-medium,
.btn-small {
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s ease;
}

/* Off Canvas Pattern */
.off-canvas-demo {
    position: relative;
    height: 250px;
    background: var(--color-background);
    border-radius: 8px;
    overflow: hidden;
}

.menu-toggle {
    position: absolute;
    top: 1rem;
    left: 1rem;
    z-index: 1001;
    background: var(--color-primary);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
}

.off-canvas-nav {
    position: absolute;
    top: 0;
    left: -250px;
    width: 250px;
    height: 100%;
    background: #333;
    color: white;
    transition: left 0.3s ease;
    z-index: 1000;
}

.off-canvas-nav.active {
    left: 0;
}

.nav-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid #555;
}

.close-nav {
    background: none;
    border: none;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
}

.nav-menu {
    padding: 1rem 0;
}

.nav-menu a {
    display: block;
    color: white;
    text-decoration: none;
    padding: 0.75rem 1rem;
    border-bottom: 1px solid #555;
    transition: background 0.2s ease;
}

.nav-menu a:hover {
    background: #555;
}

.main-content {
    padding: 1rem;
    margin-left: 0;
    transition: margin-left 0.3s ease;
    height: 100%;
    overflow-y: auto;
}

.main-content.shifted {
    margin-left: 250px;
}

.main-content h4 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.5);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
}

.overlay.active {
    opacity: 1;
    visibility: visible;
}

.pattern-code {
    background: var(--color-code-bg);
    border-radius: 8px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.pattern-code code {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--color-text);
}

/* ==========================================================================
   Responsive Images Demo
   ========================================================================== */

.responsive-images-demo {
    background: var(--color-surface);
    border-radius: 16px;
    overflow: hidden;
    border: 2px solid var(--color-border);
}

.image-techniques {
    padding: 2rem;
}

.technique-tabs {
    display: flex;
    background: var(--color-card);
    border-bottom: 2px solid var(--color-border);
    overflow-x: auto;
    margin: -2rem -2rem 2rem -2rem;
}

.technique-tab {
    padding: 1rem 1.5rem;
    background: none;
    border: none;
    color: var(--color-text-light);
    cursor: pointer;
    font-weight: 600;
    white-space: nowrap;
    transition: all 0.3s ease;
    position: relative;
}

.technique-tab:hover {
    background: var(--color-muted);
    color: var(--color-text);
}

.technique-tab.active {
    color: var(--color-primary);
    background: var(--color-background);
}

.technique-tab.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--color-primary);
}

.technique-content {
    /* Content styles */
}

.technique-demo {
    display: none;
    animation: fadeIn 0.3s ease;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.technique-demo.active {
    display: grid;
}

.demo-area {
    background: var(--color-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.technique-code {
    background: var(--color-code-bg);
    border-radius: 8px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.technique-code code {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.6;
    color: var(--color-text);
}

/* Fluid Images */
.fluid-container {
    position: relative;
    border: 2px dashed var(--color-border);
    border-radius: 8px;
    padding: 1rem;
    resize: horizontal;
    overflow: auto;
    min-width: 200px;
    max-width: 400px;
}

.fluid-image {
    width: 100%;
}

.image-placeholder {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-accent));
    color: white;
    aspect-ratio: 16/9;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    border-radius: 6px;
}

.resize-handle {
    position: absolute;
    bottom: 0.5rem;
    right: 0.5rem;
    background: var(--color-primary);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    cursor: e-resize;
}

/* Srcset Demo */
.device-comparison {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.device {
    text-align: center;
}

.device-screen {
    background: #333;
    border-radius: 8px;
    padding: 4px;
    margin-bottom: 0.5rem;
}

.device.mobile .device-screen {
    width: 60px;
    height: 100px;
}

.device.tablet .device-screen {
    width: 80px;
    height: 60px;
}

.device.desktop .device-screen {
    width: 100px;
    height: 60px;
}

.demo-image {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    font-weight: 600;
    border-radius: 4px;
}

.device p {
    font-size: 0.75rem;
    color: var(--color-text-light);
    margin: 0;
}

/* Picture Element Demo */
.format-comparison {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.format-demo {
    text-align: center;
    flex: 1;
}

.format-image {
    background: linear-gradient(135deg, var(--color-accent), var(--color-warning));
    color: white;
    aspect-ratio: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    border-radius: 8px;
    margin-bottom: 0.5rem;
}

/* Art Direction Demo */
.viewport-images {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.viewport-image {
    text-align: center;
    flex: 1;
}

.art-image {
    background: linear-gradient(135deg, var(--color-success), var(--color-primary));
    color: white;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    border-radius: 8px;
    margin-bottom: 0.5rem;
}

.art-image.landscape {
    aspect-ratio: 16/9;
}

.art-image.portrait {
    aspect-ratio: 9/16;
}

.viewport-image p {
    font-size: 0.85rem;
    color: var(--color-text-light);
    margin: 0;
}

/* ==========================================================================
   Responsive Challenge
   ========================================================================== */

.responsive-challenge {
    background: var(--color-surface);
    border-radius: 16px;
    border: 2px solid var(--color-border);
    overflow: hidden;
}

.challenge-description {
    background: var(--color-card);
    padding: 2rem;
    border-bottom: 2px solid var(--color-border);
}

.challenge-description h4 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
}

.challenge-description p {
    margin: 0 0 1.5rem 0;
    color: var(--color-text-light);
}

.requirements {
    background: var(--color-muted);
    padding: 1.5rem;
    border-radius: 8px;
}

.requirements h5 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
}

.requirements ul {
    margin: 0;
    padding-left: 1.5rem;
}

.requirements li {
    margin-bottom: 0.5rem;
    color: var(--color-text-light);
}

.challenge-workspace {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    padding: 2rem;
}

.challenge-editor,
.challenge-preview {
    background: var(--color-card);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--color-border);
}

.challenge-editor h5,
.challenge-preview h5 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
}

#challenge-css {
    width: 100%;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.5;
    padding: 1rem;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-code-bg);
    color: var(--color-text);
    resize: vertical;
    min-height: 200px;
}

#challenge-css:focus {
    outline: none;
    border-color: var(--color-primary);
}

.test-btn {
    background: var(--color-primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    margin-top: 1rem;
    transition: all 0.2s ease;
}

.test-btn:hover {
    background: var(--color-secondary);
    transform: translateY(-1px);
}

.preview-controls {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.preview-btn {
    padding: 0.5rem 0.75rem;
    background: var(--color-background);
    border: 2px solid var(--color-border);
    border-radius: 6px;
    color: var(--color-text);
    cursor: pointer;
    font-weight: 600;
    font-size: 0.8rem;
    transition: all 0.2s ease;
}

.preview-btn:hover {
    background: var(--color-muted);
}

.preview-btn.active {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

.challenge-preview-frame {
    background: var(--color-background);
    border: 2px solid var(--color-border);
    border-radius: 8px;
    padding: 1rem;
    transition: all 0.3s ease;
    overflow: hidden;
}

.challenge-preview-frame.mobile {
    max-width: 320px;
}

.challenge-preview-frame.tablet {
    max-width: 768px;
}

.challenge-preview-frame.desktop {
    max-width: 1024px;
}

.challenge-preview-frame.large {
    max-width: 1200px;
    margin: 0 auto;
}

.card-container {
    display: grid;
    gap: 1rem;
    grid-template-columns: 1fr;
}

.card {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-accent));
    color: white;
    padding: 2rem 1rem;
    border-radius: 8px;
    text-align: center;
    font-weight: 600;
    font-size: 1.1rem;
}

.challenge-feedback {
    background: var(--color-card);
    padding: 1.5rem;
    border-top: 2px solid var(--color-border);
    text-align: center;
}

.challenge-feedback.success {
    background: var(--color-success);
    color: white;
}

.challenge-feedback code {
    font-family: var(--font-mono);
    background: rgba(255,255,255,0.1);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
}

/* ==========================================================================
   Best Practices Grid
   ========================================================================== */

.best-practices-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
}

.practice-card {
    background: var(--color-card);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--color-border);
    transition: transform 0.2s ease;
}

.practice-card:hover {
    transform: translateY(-2px);
}

.practice-card h4 {
    margin: 0 0 1rem 0;
    color: var(--color-primary);
    font-size: 1.1rem;
}

.practice-card ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.practice-card li {
    padding: 0.5rem 0;
    color: var(--color-text-light);
    border-bottom: 1px solid var(--color-border);
    position: relative;
    padding-left: 1.5rem;
}

.practice-card li:last-child {
    border-bottom: none;
}

.practice-card li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: bold;
}

.practice-card code {
    font-family: var(--font-mono);
    background: var(--color-muted);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    color: var(--color-primary);
    font-weight: 600;
}

/* ==========================================================================
   Responsive Design
   ========================================================================== */

@media (max-width: 1200px) {
    .media-queries-playground {
        grid-template-columns: 1fr;
    }
    
    .viewport-comparison {
        grid-template-columns: 1fr;
    }
    
    .challenge-workspace {
        grid-template-columns: 1fr;
    }
    
    .technique-demo {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .device-selector {
        flex-direction: column;
    }
    
    .responsive-stages {
        grid-template-columns: 1fr;
    }
    
    .pattern-tabs,
    .technique-tabs {
        flex-direction: column;
    }
    
    .pattern-tab,
    .technique-tab {
        text-align: left;
    }
    
    .best-practices-grid {
        grid-template-columns: 1fr;
    }
    
    .device-comparison,
    .format-comparison,
    .viewport-images {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    .preview-controls {
        flex-wrap: wrap;
    }
}

/* ==========================================================================
   Animation and Transitions
   ========================================================================== */

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(0);
    }
}

/* ==========================================================================
   Print Styles
   ========================================================================== */

@media print {
    .device-selector,
    .pattern-tabs,
    .technique-tabs,
    .preview-controls,
    .apply-btn,
    .test-btn,
    .menu-toggle {
        display: none;
    }
    
    .pattern-demo,
    .technique-demo {
        display: block !important;
        page-break-inside: avoid;
        margin-bottom: 2rem;
    }
    
    .demo-area,
    .pattern-visualization {
        border: 2px solid #000;
        background: white !important;
    }
}

/* ==========================================================================
   Dark Mode Enhancements
   ========================================================================== */

@media (prefers-color-scheme: dark) {
    .mockup-screen {
        background: #222;
        color: white;
    }
    
    .device-mockup::before {
        background: #999;
    }
    
    #responsive-frame {
        background: #1a1a1a;
    }
    
    .layout-preview {
        background: #2a2a2a;
        border-color: #444;
    }
}

/* ==========================================================================
   Accessibility Enhancements
   ========================================================================== */

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.device-btn:focus,
.pattern-tab:focus,
.technique-tab:focus,
.preview-btn:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
    .pattern-demo,
    .technique-demo,
    .practice-card,
    .off-canvas-nav,
    .overlay,
    .main-content {
        animation: none;
        transition: none;
    }
}