:root {
    --primary-color: #4f46e5;
    --secondary-color: #06b6d4;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --dark-color: #1e293b;
    --light-color: #f8fafc;
    --text-color: #334155;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Poppins', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: #ffffff;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    color: var(--dark-color);
}



/* Hero Section */
.hero-section {
    padding: 20px 0 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 2;
}

.hero-section .badge {
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 500;
}

.hero-section h1 {
    color: white;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.hero-section .lead {
    color: rgba(255, 255, 255, 0.95);
    font-size: 1.1rem;
}

.hero-image {
    position: relative;
    z-index: 2;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

/* Section Styling */
.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.section-header p {
    font-size: 1.1rem;
}

/* Concept Cards */
.concept-card {
    background: white;
    border-radius: 16px;
    padding: 30px;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    height: 100%;
    border: 2px solid transparent;
}

.concept-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.concept-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: white;
    font-size: 2rem;
}

.concept-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--dark-color);
}

.concept-card p {
    color: var(--text-color);
    margin-bottom: 20px;
}

.example-box {
    background: var(--light-color);
    border-left: 4px solid var(--primary-color);
    padding: 15px;
    border-radius: 8px;
    font-style: italic;
}

/* Rules Section */
.rules-card {
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
}

.rule-step {
    display: flex;
    gap: 25px;
    margin-bottom: 30px;
    padding-bottom: 30px;
    border-bottom: 2px solid var(--border-color);
}

.rule-step:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.step-number {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    flex-shrink: 0;
}

.step-content h4 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.step-content p {
    margin-bottom: 8px;
    color: var(--text-color);
}

.step-content ul {
    list-style: none;
    padding-left: 0;
}

.step-content ul li {
    padding: 8px 0;
    padding-left: 25px;
    position: relative;
}

.step-content ul li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success-color);
    font-weight: bold;
}

/* Example Section */
.example-group {
    background: white;
    border-radius: 16px;
    padding: 30px;
    box-shadow: var(--shadow-md);
    height: 100%;
}

.example-group h4 {
    font-size: 1.3rem;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 3px solid var(--primary-color);
}

.example-list {
    list-style: none;
    padding-left: 0;
}

.example-list li {
    padding: 12px 0;
    padding-left: 30px;
    position: relative;
    font-size: 1.05rem;
    transition: all 0.3s ease;
}

.example-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.2rem;
}

.example-list li:hover {
    padding-left: 35px;
    color: var(--primary-color);
}

.example-list li strong {
    color: var(--primary-color);
    font-weight: 600;
}

/* Quiz Section */
.quiz-container {
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
}

.quiz-question {
    margin-bottom: 40px;
    padding: 30px;
    background: var(--light-color);
    border-radius: 12px;
    border-left: 5px solid var(--primary-color);
}

.quiz-question h4 {
    color: var(--dark-color);
    font-size: 1.2rem;
}

.question-text {
    font-size: 1.15rem;
    font-weight: 500;
    margin-bottom: 20px;
    color: var(--dark-color);
}

.form-check {
    padding: 15px;
    margin-bottom: 10px;
    border-radius: 8px;
    transition: all 0.3s ease;
    cursor: pointer;
}

.form-check:hover {
    background: white;
    box-shadow: var(--shadow-sm);
}

.form-check-input {
    width: 20px;
    height: 20px;
    margin-top: 4px;
    cursor: pointer;
}

.form-check-input:checked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.form-check-label {
    font-size: 1.05rem;
    cursor: pointer;
    padding-left: 10px;
}

/* Results */
.results-container {
    animation: slideIn 0.5s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.results-container .alert {
    border-radius: 12px;
    border: none;
    box-shadow: var(--shadow-md);
}

.results-container .alert-success {
    background: linear-gradient(135deg, #10b981, #059669);
    color: white;
}

.results-container .alert-warning {
    background: linear-gradient(135deg, #f59e0b, #d97706);
    color: white;
}

.results-container .alert-danger {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
}

.answer-item {
    background: white;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 15px;
    border-left: 5px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.answer-item.correct {
    border-left-color: var(--success-color);
    background: rgba(16, 185, 129, 0.05);
}

.answer-item.incorrect {
    border-left-color: var(--danger-color);
    background: rgba(239, 68, 68, 0.05);
}

.answer-item h5 {
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.answer-item p {
    margin-bottom: 5px;
}

.answer-item .badge {
    font-size: 0.9rem;
    padding: 5px 12px;
}

/* FAQ Section */
.accordion-item {
    border: none;
    margin-bottom: 15px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.accordion-button {
    background: white;
    color: var(--dark-color);
    font-weight: 600;
    font-size: 1.1rem;
    padding: 20px 25px;
    border: none;
}

.accordion-button:not(.collapsed) {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: none;
}

.accordion-button:focus {
    box-shadow: none;
    border: none;
}

.accordion-button::after {
    filter: brightness(0) invert(1);
}

.accordion-button:not(.collapsed)::after {
    filter: brightness(1) invert(0);
}

.accordion-body {
    padding: 25px;
    font-size: 1.05rem;
    color: var(--text-color);
    line-height: 1.8;
}

/* CTA Section */

.cta-section {
    position: relative;
    overflow: hidden;
}

.cta-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: moveBackground 20s linear infinite;
}



@keyframes moveBackground {
    0% { transform: translate(0, 0); }
    100% { transform: translate(50px, 50px); }
}

/* Buttons */
.btn {
    border-radius: 10px;
    padding: 12px 30px;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border: none;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(79, 70, 229, 0.4);
}

.btn-outline-primary {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-outline-primary:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-2px);
}

.btn-light {
    background: white;
    color: var(--primary-color);
}

.btn-light:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(255, 255, 255, 0.3);
}

.btn-outline-light {
    border-color: white;
    color: white;
}

.btn-outline-light:hover {
    background: white;
    color: var(--primary-color);
}

.btn-lg {
    padding: 15px 35px;
    font-size: 1.1rem;
}

/* Footer */
.footer {
    background: linear-gradient(135deg, #1e293b, #334155);
    color: rgba(255, 255, 255, 0.9);
    padding: 60px 0 20px;
    margin-top: 80px;
}

.footer h5 {
    color: white;
    font-size: 1.3rem;
    margin-bottom: 20px;
    font-weight: 600;
}

.footer p {
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.8;
}

.footer .social-icons a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border-radius: 50%;
    margin-right: 10px;
    transition: all 0.3s ease;
}

.footer .social-icons a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-links {
    list-style: none;
    padding-left: 0;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: all 0.3s ease;
}

.footer-links a:hover {
    color: white;
    padding-left: 5px;
}

.footer .copyright {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
}

.footer-logo {
    background: white;
    padding: 10px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero-section {
        padding: 60px 0;
    }
    
    .hero-section h1 {
        font-size: 2rem;
    }
    
    .section-header h2 {
        font-size: 1.8rem;
    }
    
    .rule-step {
        flex-direction: column;
        gap: 15px;
    }
    
    .quiz-question {
        padding: 20px;
    }
    
    .btn-lg {
        padding: 12px 25px;
        font-size: 1rem;
    }
}

/* Utility Classes */
.text-gradient {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.shadow-custom {
    box-shadow: var(--shadow-lg);
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}