/* style.css (Version 3: Professional Centered Layout) */
@import url('https://fonts.googleapis.com/css2?family=Roboto+Mono:wght@400;700&family=Noto+Sans+SC:wght@400;700&display=swap');

:root {
    --bg-color: #F9F9F7;
    --text-color: #333333;
    --heading-color: #1A1A1A;
    --primary-color: #D06519;
    --accent-color: #8A4A12;
    --code-bg-color: #F3F4F6;
    --code-text-color: #0B598E;
    --border-color: #E5E7EB;
    --warning-text-color: #B91C1C;
    --warning-bg-color: #FEF2F2;
    --success-color: #059669;
    --success-bg-color: #F0FDF4;
    --info-color: #0284C7;
    --info-bg-color: #F0F9FF;
}

* {
    box-sizing: border-box;
}

body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    font-family: "Tiempos", serif;
    background-color: #EAEAEA;
    color: var(--text-color);
    overflow: hidden;
}

#presentation {
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    position: relative;
    overflow: hidden;
}

.slide {
    width: 100%;
    height: 100%;
    padding: 60px 80px; /* Increased padding for better spacing */
    display: none;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center; /* Center the main content container */
    overflow-y: auto;
}

.slide.active {
    display: flex;
    animation: fadeIn 0.5s ease-in-out;
}

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

/* NEW: The main content container for consistent width and alignment */
.slide-content {
    width: 100%;
    max-width: 1100px; /* Optimal reading width on large screens */
    text-align: left;
}

.slide.title-slide {
    text-align: center;
}

.slide h1 {
    font-size: 3.8em; /* Slightly larger for impact */
    color: var(--heading-color);
    margin: 0;
}

.slide h2 {
    font-size: 2.4em; /* Larger for better visibility */
    color: var(--heading-color);
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 10px;
    margin-top: 0;
    width: 100%;
}

.slide h3 {
    font-size: 1.6em; /* Larger */
    color: var(--primary-color);
    margin-top: 30px;
    margin-bottom: 15px;
}

.slide p, .slide li {
    font-size: 1.2em; /* Larger for classroom readability */
    line-height: 1.7;
    max-width: 100%; /* Keep line length comfortable */
}

.slide ul, .slide ol {
    padding-left: 30px;
}

.slide li + li {
    margin-top: 12px;
}

pre {
    background-color: var(--code-bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px; /* Softer radius */
    padding: 20px;
    width: 100%;
    overflow-x: auto;
    font-family: "Styrene", sans-serif;
    color: #333;
    font-size: 1.05em; /* Make code slightly larger */
}

code {
    font-family: "Copernicus", sans-serif;
    color: var(--code-text-color);
    background-color: rgba(0, 0, 0, 0.05);
    padding: 3px 6px;
    border-radius: 4px;
}

pre code {
    background-color: transparent;
    padding: 0;
}

strong {
    color: var(--accent-color);
}

.warning {
    color: var(--warning-text-color);
    background-color: var(--warning-bg-color);
    border-left: 4px solid var(--warning-text-color);
    padding: 15px 20px;
    margin: 20px 0;
    border-radius: 4px;
}

/* Controls */
.controls {
    position: absolute;
    bottom: 20px;
    right: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.controls button {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1em;
    transition: background-color 0.2s;
}

.controls button:hover {
    background-color: #E5843A;
}

.controls button:disabled {
    background-color: #D1D5DB;
    color: #6B7280;
    cursor: not-allowed;
}

#slide-counter {
    font-size: 1em;
    color: #6B7280;
}

/* Progress Bar */
.progress-bar-container {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background-color: var(--border-color);
}

#progress-bar {
    height: 100%;
    width: 0;
    background-color: var(--primary-color);
    transition: width 0.3s ease-out;
}

/* Special layout for practice slides */
.practice-container {
    display: flex;
    gap: 40px;
    width: 100%;
    margin-top: 20px;
    align-items: stretch;
}

.practice-step {
    flex: 1;
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.07);
    display: flex;
    flex-direction: column;
}

.practice-step h3 {
    margin-top: 0;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
    margin-bottom: 15px;
    color: var(--accent-color);
}

.practice-step p {
    font-size: 1em;
    flex-grow: 1;
}

.practice-step pre {
    width: 100%;
    margin-top: auto;
}

/* Table for Grading Example */
.grading-example {
    width: 100%;
    margin: 25px 0;
    border-collapse: collapse;
    font-size: 1em;
}

.grading-example th,
.grading-example td {
    border: 1px solid var(--border-color);
    padding: 12px 15px;
    text-align: center;
}

.grading-example thead th {
    background-color: var(--code-bg-color);
    font-weight: 700;
}

.grading-example tfoot {
    background-color: var(--code-bg-color);
    font-weight: 700;
}

.grading-example td:last-child,
.grading-example th:last-child {
    text-align: right;
}

/* Introduction Block Style */
.intro-block {
    background-color: var(--info-bg-color);
    border-left: 5px solid var(--info-color);
    padding: 20px;
    margin: 25px 0;
    border-radius: 4px;
    font-size: 1.1em;
    line-height: 1.7;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.intro-block p {
    margin-bottom: 15px;
}

.intro-block p:last-child {
    margin-bottom: 0;
}


.grading-example td:first-child,
.grading-example th:first-child {
    text-align: left;
}

/* Answer section hover effect */
.answer-section {
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out;
}

.practice-container:hover .answer-section {
    opacity: 1;
    visibility: visible;
}

/* Dialogue Example Styles */

/* Code Comparison Styles */
.code-comparison {
    display: flex;
    justify-content: space-between;
    gap: 2rem;
    margin: 2rem 0;
}

.comparison-item {
    flex: 1;
    background: var(--slide-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.comparison-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.comparison-item h4 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.2rem;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 0.5rem;
}

.comparison-item pre {
    background: var(--code-bg);
    border-radius: 4px;
    padding: 1rem;
    margin: 1rem 0;
}

.comparison-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.5;
}
.dialogue-example {
    margin: 25px 0;
    padding: 20px;
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.07);
}

.dialogue-item {
    font-size: 1.3em; /* 放大字体 */
    line-height: 1.8;
    margin-bottom: 15px;
    padding: 10px;
    border-left: 4px solid var(--primary-color);
    background-color: rgba(208, 101, 25, 0.05);
}

.dialogue-item:last-child {
    margin-bottom: 0;
}

.annotation {
    font-size: 0.9em;
    color: #6B7280;
    font-style: italic;
    margin-left: 10px;
}

/* Access Modifier Table Styles */
.access-modifier-table {
    width: 80%; /* 加宽表格 */
    margin: 20px auto; /* 居中显示 */
    border-collapse: collapse; /* 合并边框 */
    border: 1px solid var(--accent-color); /* 添加外边框 */
}

.access-modifier-table th,
.access-modifier-table td {
    border: 1px solid var(--accent-color); /* 为单元格添加边框 */
    padding: 12px;
    text-align: center;
}

.access-modifier-table th {
    background-color: var(--secondary-bg-color);
    color: var(--accent-color);
}

/* Singleton Pattern Styles */
.singleton-types {
    margin: 20px 0;
    width: 100%;
}

.singleton-types h3 {
    color: var(--heading-color);
    margin-bottom: 15px;
    text-align: center;
}

.comparison-container {
    display: flex;
    gap: 20px;
    margin: 20px 0;
}

.lazy-singleton,
.eager-singleton {
    flex: 1;
    background-color: #F8F9FA;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 15px;
}

.lazy-singleton h4,
.eager-singleton h4 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 10px;
    font-size: 1.1em;
}

.lazy-singleton p,
.eager-singleton p {
    margin: 5px 0 10px 0;
    font-size: 0.9em;
    color: #666;
}

.framework-examples {
    margin: 20px 0;
    width: 100%;
}

.framework-examples h3 {
    color: var(--heading-color);
    margin-bottom: 15px;
    text-align: center;
}

.framework-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.framework-list li {
    background-color: #F8F9FA;
    border-left: 4px solid var(--primary-color);
    padding: 10px 15px;
    margin: 8px 0;
    border-radius: 0 4px 4px 0;
}

.framework-list li strong {
    color: var(--primary-color);
}

/* Lambda Expression Specific Styles */
.lambda-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin: 30px 0;
    font-size: 2em;
}

.lambda-symbol {
    color: var(--primary-color);
    font-size: 3em;
    font-weight: bold;
}

.arrow {
    color: var(--accent-color);
    font-size: 2em;
}

.code-snippet {
    color: var(--code-text-color);
    font-family: "Roboto Mono", monospace;
    background-color: var(--code-bg-color);
    padding: 10px 15px;
    border-radius: 5px;
}

.comparison {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    margin: 30px 0;
}

.before, .after {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.before h3 {
    color: #DC2626;
    margin-top: 0;
}

.after h3 {
    color: #059669;
    margin-top: 0;
}

.highlight {
    background-color: #FEF3C7;
    border-left: 4px solid #F59E0B;
    padding: 15px 20px;
    margin: 20px 0;
    border-radius: 4px;
    font-weight: 500;
}

.syntax-breakdown {
    background-color: #F8F9FA;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    margin: 20px 0;
}

.syntax-example {
    text-align: center;
    margin: 20px 0;
}

.syntax-parts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.part {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.part-name {
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.part-desc {
    font-size: 0.9em;
    color: #666;
}

.interface-examples {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
}

.interface-card {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.interface-card h3 {
    color: var(--primary-color);
    margin-top: 0;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.interfaces-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.interface-item {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.interface-item h3 {
    color: var(--primary-color);
    margin-top: 0;
    font-family: "Roboto Mono", monospace;
}

.interface-item p {
    color: #666;
    font-size: 1em;
    margin: 10px 0;
}

/* 垂直布局样式 */

/* 类型擦除互动挑战样式 */
.challenge-intro {
    background: linear-gradient(135deg, var(--info-bg-color) 0%, var(--success-bg-color) 100%);
    border-radius: 12px;
    padding: 25px;
    margin: 30px 0;
    text-align: center;
    border-left: 6px solid var(--primary-color);
}

.challenge-intro h3 {
    color: var(--primary-color);
    margin-top: 0;
    font-size: 1.8em;
}

.challenge-intro p {
    font-size: 1.1em;
    color: var(--text-color);
    margin-bottom: 0;
}

.interactive-challenges {
    margin: 40px 0;
}

.challenge {
    background: #FFFFFF;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: 30px;
    margin: 25px 0;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.challenge:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.challenge h4 {
    color: var(--primary-color);
    font-size: 1.4em;
    margin-top: 0;
    margin-bottom: 20px;
    border-bottom: 3px solid var(--accent-color);
    padding-bottom: 10px;
}

.code-options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    margin: 20px 0;
}

.option {
    background: var(--code-bg-color);
    border: 2px dashed var(--accent-color);
    border-radius: 8px;
    padding: 20px;
    text-align: center;
}

.option h5 {
    color: var(--accent-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.2em;
}

.code-puzzle {
    background: var(--code-bg-color);
    border: 2px solid var(--primary-color);
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.answer-box {
    background: var(--success-bg-color);
    border: 2px solid var(--success-color);
    border-radius: 8px;
    padding: 20px;
    margin-top: 25px;
    position: relative;
    overflow: hidden;
}

.answer-box::before {
    content: "🎯";
    position: absolute;
    top: -10px;
    right: 15px;
    font-size: 3em;
    opacity: 0.2;
}

.answer-box h5 {
    color: var(--success-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.3em;
}

.answer-box p, .answer-box ul {
    margin-bottom: 10px;
}

.answer-box li {
    margin-bottom: 8px;
}

.key-takeaways {
    background: linear-gradient(135deg, var(--info-bg-color) 0%, var(--success-bg-color) 100%);
    border-radius: 12px;
    padding: 30px;
    margin: 40px 0;
    border-left: 6px solid var(--primary-color);
}

.key-takeaways h3 {
    color: var(--primary-color);
    text-align: center;
    margin-top: 0;
    margin-bottom: 25px;
    font-size: 1.8em;
}

.takeaways-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.takeaway {
    background: #FFFFFF;
    border-radius: 8px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

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

.takeaway h4 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 10px;
    font-size: 1.1em;
}

.takeaway p {
    color: var(--text-color);
    margin: 0;
    font-size: 0.95em;
    line-height: 1.4;
}

.final-wisdom {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
    border-radius: 12px;
    padding: 30px;
    margin: 40px 0;
    color: #FFFFFF;
    text-align: center;
}

.final-wisdom h3 {
    color: #FFFFFF;
    margin-top: 0;
    margin-bottom: 20px;
    font-size: 1.8em;
}

.wisdom-box {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: 20px;
    backdrop-filter: blur(10px);
}

.wisdom-box p {
    color: #FFFFFF;
    margin-bottom: 15px;
    font-size: 1.1em;
    line-height: 1.6;
}

.wisdom-box p:last-child {
    margin-bottom: 0;
}

.wisdom-box strong {
    color: #FFFFFF;
    font-weight: bold;
}

/* 类型擦除部分特殊样式 */
.type-erasure-intro {
    background: linear-gradient(135deg, var(--info-bg-color) 0%, var(--code-bg-color) 100%);
    border-radius: 12px;
    padding: 25px;
    margin: 30px 0;
    border-left: 6px solid var(--primary-color);
}

.type-erasure-intro h3 {
    color: var(--primary-color);
    margin-top: 0;
    font-size: 1.6em;
}

.code-transformation {
    background: var(--code-bg-color);
    border: 2px solid var(--primary-color);
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.transformation-step {
    background: #FFFFFF;
    border-radius: 6px;
    padding: 15px;
    margin: 15px 0;
    border-left: 4px solid var(--accent-color);
}

.transformation-step h4 {
    color: var(--accent-color);
    margin-top: 0;
    margin-bottom: 10px;
}

.insight-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin: 20px 0;
}

.insight-item {
    background: #FFFFFF;
    border-radius: 6px;
    padding: 15px;
    border-left: 4px solid var(--primary-color);
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.1);
}

.insight-item strong {
    color: var(--primary-color);
}

.historical-crossroads {
    background: linear-gradient(135deg, var(--warning-bg-color) 0%, var(--code-bg-color) 100%);
    border-radius: 12px;
    padding: 25px;
    margin: 30px 0;
    border-left: 6px solid var(--warning-text-color);
}

.historical-crossroads h3 {
    color: var(--warning-text-color);
    margin-top: 0;
    font-size: 1.6em;
}

.choice-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    margin: 25px 0;
}

.choice-option {
    background: #FFFFFF;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.choice-option.revolution {
    border-left: 4px solid #DC2626;
}

.choice-option.compromise {
    border-left: 4px solid var(--success-color);
}

.choice-option h4 {
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.2em;
}

.choice-option.revolution h4 {
    color: #DC2626;
}

.choice-option.compromise h4 {
    color: var(--success-color);
}

.limitations-showcase {
    background: var(--warning-bg-color);
    border: 2px solid var(--warning-text-color);
    border-radius: 12px;
    padding: 25px;
    margin: 30px 0;
}

.limitations-showcase h3 {
    color: var(--warning-text-color);
    margin-top: 0;
    font-size: 1.6em;
}

.wrong-code, .correct-code {
    border-radius: 6px;
    padding: 15px;
    margin: 15px 0;
}

.wrong-code {
    background: #FEE2E2;
    border-left: 4px solid #DC2626;
}

.wrong-code h4 {
    color: #DC2626;
    margin-top: 0;
}

.correct-code {
    background: var(--success-bg-color);
    border-left: 4px solid var(--success-color);
}

.correct-code h4 {
    color: var(--success-color);
    margin-top: 0;
}

.bridge-method-demo {
    background: var(--code-bg-color);
    border: 2px solid var(--primary-color);
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.bridge-method-demo h4 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.2em;
}

.method-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin: 20px 0;
}

.method-box {
    background: #FFFFFF;
    border-radius: 6px;
    padding: 15px;
    border-left: 4px solid var(--accent-color);
}

.method-box h5 {
    color: var(--accent-color);
    margin-top: 0;
    margin-bottom: 10px;
}

/* 垂直布局样式 */
.interfaces-vertical {
    display: flex;
    flex-direction: column;
    gap: 25px;
    margin: 30px 0;
}

.interface-section {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.interface-section:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.interface-section h3 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-family: "Roboto Mono", monospace;
    font-size: 1.3em;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 8px;
}

.interface-section p {
    color: #555;
    font-size: 1.1em;
    margin: 15px 0;
    line-height: 1.6;
}

.interface-section pre {
    margin-top: 20px;
    background-color: #F8F9FA;
    border-left: 4px solid var(--primary-color);
}

.stream-example {
    background-color: #F8F9FA;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    margin: 20px 0;
}

.stream-operations {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.stream-operations ul {
    list-style: none;
    padding: 0;
}

.stream-operations li {
    background-color: #F3F4F6;
    border-left: 4px solid var(--primary-color);
    padding: 10px 15px;
    margin: 8px 0;
    border-radius: 0 4px 4px 0;
}

.method-ref-types {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin: 30px 0;
}

.ref-type {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.ref-type h3 {
    color: var(--primary-color);
    margin-top: 0;
}

.practical-example {
    background-color: #F8F9FA;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    margin: 20px 0;
}

.best-practices-section {
    margin: 30px 0;
}

.best-practices-section h3 {
    color: var(--primary-color);
    font-size: 1.5em;
    margin-bottom: 20px;
    text-align: center;
}

.best-practices {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin: 20px 0;
}

.practice-item {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
}

.practice-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
}

.practice-item h3 {
    color: #059669;
    margin-top: 0;
}

.practice-item h4 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.1em;
    font-weight: 600;
}

.summary-points {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin: 30px 0;
}

.summary-item {
    background-color: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.summary-item h3 {
    color: var(--primary-color);
    margin-top: 0;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.final-message {
    background-color: #EFF6FF;
    border: 2px solid #3B82F6;
    border-radius: 8px;
    padding: 25px;
    margin: 30px 0;
    text-align: center;
}

.final-message p {
    color: #1E40AF;
    font-size: 1.3em;
    margin: 0;
}

/* Collections Framework Specific Styles */
.collections-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
    margin: 30px 0;
    font-size: 1.5em;
}

.collection-icon {
    font-size: 2em;
    color: var(--primary-color);
}

.concept-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
}

.concept-item {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-left: 4px solid var(--primary-color);
}

.concept-item h3 {
    margin-top: 0;
    color: var(--primary-color);
}

/* Hierarchy Diagram */
.hierarchy-diagram {
    margin: 30px 0;
}

.interface-level, .subinterface-level, .implementation-level {
    margin-bottom: 30px;
}

.interface-boxes, .subinterface-boxes {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin: 20px 0;
}

.interface-box, .subinterface-box {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    min-width: 150px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.interface-box.map {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

.subinterface-box.list {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

.subinterface-box.set {
    background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
}

.subinterface-box.queue {
    background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
}

.impl-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin: 20px 0;
}

.impl-group {
    background: white;
    padding: 15px;
    border-radius: 8px;
    border: 2px solid var(--border-color);
    text-align: center;
}

.impl-group h4 {
    margin: 0 0 10px 0;
    color: var(--primary-color);
}

/* List Comparison */
.list-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
}

.list-type {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.features {
    margin: 15px 0;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 5px;
}

.performance-table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.performance-table th,
.performance-table td {
    padding: 12px 15px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.performance-table th {
    background: var(--primary-color);
    color: white;
    font-weight: bold;
}

.performance-table .good {
    background: #d4edda;
    color: #155724;
    font-weight: bold;
}

.performance-table .average {
    background: #fff3cd;
    color: #856404;
    font-weight: bold;
}

.performance-table .bad {
    background: #f8d7da;
    color: #721c24;
    font-weight: bold;
}

/* Set Types */
.set-types {
    display: grid;
    grid-template-columns: 1fr;
    gap: 25px;
    margin: 30px 0;
}

.set-type {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-left: 4px solid var(--primary-color);
}

/* Map Types */
.map-types {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
}

.map-type {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.map-usage {
    margin: 30px 0;
}

.usage-examples {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    margin: 20px 0;
}

.usage-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

/* Queue Types */
.queue-types {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin: 30px 0;
}

.queue-type {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.queue-applications {
    margin: 30px 0;
}

.application-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 20px 0;
}

.app-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: center;
    border-top: 4px solid var(--primary-color);
}

/* Example System */
.example-system {
    margin: 30px 0;
}

.system-overview {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 25px;
}

.code-example {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

/* Performance Guide */
.performance-guide {
    margin: 30px 0;
}

.performance-table-container {
    margin-bottom: 30px;
}

.selection-guide {
    margin: 30px 0;
}

.guide-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 20px 0;
}

.guide-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-left: 4px solid var(--primary-color);
}

.guide-item h4 {
    margin-top: 0;
    color: var(--primary-color);
}

/* Summary Content */
.summary-content {
    margin: 30px 0;
}

.key-points {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

.best-practices {
    margin: 30px 0;
}



.conclusion {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    margin: 30px 0;
    max-width: 100%;
    box-sizing: border-box;
}

.conclusion .highlight {
    font-size: 1.3em;
    font-weight: bold;
    margin: 0;
}

/* Assignment Requirements Styles */
.assignment-requirements {
    background: linear-gradient(135deg, #f8fafc, #e2e8f0);
    border-radius: 15px;
    padding: 30px;
    margin: 20px 0;
    border: 2px solid var(--primary-color);
}

.assignment-header {
    text-align: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--primary-color);
}

.assignment-header h3 {
    color: var(--primary-color);
    font-size: 1.8em;
    margin-bottom: 15px;
}

.assignment-intro {
    font-size: 1.1em;
    color: #4a5568;
    line-height: 1.6;
    max-width: 800px;
    margin: 0 auto;
}

.requirements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 25px;
    margin: 30px 0;
}

.requirement-section {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    border-left: 5px solid var(--accent-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.requirement-section:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.requirement-section h4 {
    color: var(--primary-color);
    font-size: 1.3em;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.requirement-section ul {
    margin: 0;
    padding-left: 20px;
}

.requirement-section li {
    margin-bottom: 8px;
    line-height: 1.5;
}

.requirement-section li strong {
    color: var(--primary-color);
}

.requirement-section ul ul {
    margin-top: 8px;
    margin-bottom: 8px;
}

.requirement-section ul ul li {
    margin-bottom: 4px;
    font-size: 0.95em;
    color: #5a6c7d;
}

.assignment-footer {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    margin-top: 30px;
}

.highlight-note {
    font-size: 1.1em;
    margin: 0;
    font-weight: 600;
}

.highlight-note strong {
    color: #ffd700;
}


/* Enhanced Responsive Design */

/* Tablets and Large Phones */
@media (max-width: 1024px) {
    .slide {
        padding: 50px 40px;
    }

    .slide-content {
        max-width: 100%;
    }

    .slide h1 {
        font-size: 3.2em;
    }

    .slide h2 {
        font-size: 2.2em;
    }

    .slide h3 {
        font-size: 1.4em;
    }

    .impl-grid {
        grid-template-columns: 1fr;
    }

    .guide-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .application-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Mobile Phones */
@media (max-width: 768px) {
    .slide {
        padding: 30px 15px;
    }

    /* Hide controls on mobile devices */
    .controls {
        display: none;
    }

    .slide h1 {
        font-size: 2.5em;
        line-height: 1.2;
    }

    .slide h2 {
        font-size: 1.8em;
        line-height: 1.3;
    }

    .slide h3 {
        font-size: 1.4em;
    }

    .slide p, .slide li {
        font-size: 1em;
        line-height: 1.6;
    }

    /* Better spacing on mobile */
    .practice-section,
    .thinking-box,
    .key-point,
    .family-intro,
    .conclusion {
        margin: 20px 0;
        padding: 20px;
    }

    /* Grid layouts to single column */
    .comparison-container {
        flex-direction: column;
        gap: 15px;
    }

    .comparison {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .before, .after {
        width: 100%;
        margin-bottom: 0;
    }

    .concept-grid,
    .list-comparison,
    .map-types,
    .queue-types,
    .usage-examples,
    .requirements-grid,
    .interface-examples,
    .interfaces-grid,
    .method-ref-types,
    .best-practices,
    .summary-points,
    .practice-container {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    /* Flexbox adjustments */
    .interface-boxes,
    .subinterface-boxes {
        flex-direction: column;
        align-items: center;
        gap: 15px;
    }

    .impl-grid,
    .guide-grid,
    .application-grid {
        grid-template-columns: 1fr;
    }

    /* Code adjustments for mobile */
    pre {
        font-size: 0.9em;
        padding: 15px;
        overflow-x: auto;
        white-space: pre-wrap;
        word-wrap: break-word;
    }

    /* Table adjustments */
    .slide-content table {
        font-size: 0.9em;
        display: block;
        overflow-x: auto;
        white-space: nowrap;
    }

    /* Make buttons and interactive elements larger for touch */
    .collections-visual {
        font-size: 1.2em;
        flex-direction: column;
        gap: 15px;
    }

    /* Navigation adjustments */
    #slide-counter {
        font-size: 0.9em;
    }
}

/* Small Mobile Phones */
@media (max-width: 480px) {
    .slide {
        padding: 20px 10px;
    }

    .slide h1 {
        font-size: 2.2em;
    }

    .slide h2 {
        font-size: 1.6em;
    }

    .slide h3 {
        font-size: 1.3em;
    }

    .slide p, .slide li {
        font-size: 0.95em;
    }

    /* Reduce padding and margins on small screens */
    .practice-section,
    .thinking-box,
    .key-point,
    .family-intro,
    .conclusion {
        margin: 15px 0;
        padding: 15px;
    }

    /* Smaller gaps in grids */
    .concept-grid,
    .comparison,
    .practice-container {
        gap: 15px;
    }

    /* Code adjustments for very small screens */
    pre {
        font-size: 0.8em;
        padding: 12px;
    }

    /* Ensure content doesn't overflow */
    .slide-content {
        max-width: 100%;
        overflow-x: hidden;
    }

    /* Adjust buttons for easier touch access */
    .controls button {
        padding: 8px 15px;
        font-size: 0.9em;
    }
}

/* Landscape orientation for mobile */
@media (max-width: 768px) and (orientation: landscape) {
    .slide {
        padding: 20px 15px;
    }

    .slide h1 {
        font-size: 2.2em;
    }

    .slide h2 {
        font-size: 1.7em;
    }
}

/* Table styles for slide content */
.slide-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 16px 0;
    background: #ffffff;
}

.slide-content thead th {
    border: 1px solid var(--border-color);
    padding: 10px 12px;
    background-color: var(--secondary-bg-color);
    color: var(--heading-color);
    font-weight: 600;
    text-align: left;
}

.slide-content tbody td {
    border: 1px solid var(--border-color);
    padding: 10px 12px;
    vertical-align: top;
}

.slide-content tbody tr:nth-child(even) {
    background-color: #f9fafb; /* subtle zebra striping for readability */
}

.slide-content table code {
    background: var(--code-bg);
    border-radius: 4px;
    padding: 2px 4px;
}

/* Comparison Table Styles */
.comparison-table {
    width: 100%;
    margin: 25px 0;
    border-collapse: collapse;
    font-size: 1em;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.comparison-table thead th {
    background-color: var(--code-bg-color);
    border: 1px solid var(--border-color);
    padding: 15px 12px;
    text-align: left;
    font-weight: 700;
    color: var(--heading-color);
}

.comparison-table tbody td {
    border: 1px solid var(--border-color);
    padding: 12px;
    vertical-align: top;
}

.comparison-table tbody tr:hover {
    background-color: rgba(208, 101, 25, 0.05);
}

.comparison-table tbody tr.highlight {
    background-color: rgba(208, 101, 25, 0.1);
    font-weight: 500;
}

.comparison-table tbody tr.highlight td {
    border-left: 4px solid var(--primary-color);
}

/* Scenario Box Styles */
.scenario-box {
    background: linear-gradient(135deg, var(--code-bg-color) 0%, #FFFFFF 100%);
    border: 2px solid var(--border-color);
    border-left: 5px solid var(--primary-color);
    border-radius: 12px;
    padding: 25px;
    margin: 25px 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.scenario-box h3 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.4em;
    border-bottom: 2px solid var(--accent-color);
    padding-bottom: 10px;
}

.scenario-box p {
    margin-bottom: 15px;
    font-size: 1.1em;
}

.scenario-box pre {
    background-color: var(--code-bg-color);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    margin: 15px 0;
}