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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #333;
    font-weight: 700;
    font-size: 1.2rem;
}

.logo {
    width: 40px;
    height: 40px;
    margin-right: 10px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: #6366f1;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    gap: 4px;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    transition: 0.3s;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    text-align: center;
}

.btn-primary {
    background: #6366f1;
    color: white;
}

.btn-primary:hover {
    background: #4f46e5;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #6366f1;
    border: 2px solid #6366f1;
}

.btn-secondary:hover {
    background: #6366f1;
    color: white;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    margin-top: 80px;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-description {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-actions {
    display: flex;
    gap: 1rem;
}

.hero-bg {
    width: 100%;
    height: auto;
    max-width: 500px;
}

/* Sections */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: #1f2937;
}

.section-subtitle {
    font-size: 1.1rem;
    text-align: center;
    color: #6b7280;
    margin-bottom: 3rem;
}

.section-actions {
    text-align: center;
    margin-top: 3rem;
}

/* Features */
.features {
    padding: 80px 0;
    background: #f8fafc;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    text-align: center;
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.feature-description {
    color: #6b7280;
}

/* Courses */
.featured-courses {
    padding: 80px 0;
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.course-card {
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    overflow: hidden;
    transition: transform 0.3s ease;
}

.course-card:hover {
    transform: translateY(-5px);
}

.course-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.course-content {
    padding: 1.5rem;
}

.course-category {
    display: inline-block;
    background: #e0e7ff;
    color: #6366f1;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.course-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1f2937;
}

.course-description {
    color: #6b7280;
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: #6b7280;
}

.course-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: #059669;
    margin-bottom: 1rem;
}

.course-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.875rem;
    flex: 1;
}

/* Trust Indicators */
.trust-indicators {
    padding: 80px 0;
    background: #f8fafc;
}

.trust-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.trust-item {
    text-align: center;
    padding: 2rem;
}

.trust-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.trust-item h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.trust-item p {
    color: #6b7280;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #374151;
}

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: 12px;
    border: 2px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: #6366f1;
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-error {
    color: #dc2626;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

.form-checkbox {
    display: flex;
    align-items: flex-start;
    gap: 0.5rem;
    margin: 1rem 0;
}

.form-checkbox input {
    margin-top: 0.25rem;
}

/* Course Detail */
.course-hero {
    padding: 120px 0 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.course-hero .container {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: start;
}

.course-hero-content h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.course-hero-sidebar {
    background: rgba(255,255,255,0.1);
    padding: 2rem;
    border-radius: 12px;
    backdrop-filter: blur(10px);
}

.course-detail {
    padding: 60px 0;
}

.course-detail .container {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
}

.course-sidebar {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    height: fit-content;
    position: sticky;
    top: 100px;
}

.content-section {
    margin-bottom: 3rem;
}

.content-section h2 {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #1f2937;
}

.content-section h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: #374151;
}

.content-list {
    list-style: none;
}

.content-list li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #e5e7eb;
    position: relative;
    padding-left: 1.5rem;
}

.content-list li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #059669;
    font-weight: bold;
}

.curriculum-list li:before {
    content: "📚";
}

.faq-item {
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    margin-bottom: 1rem;
    overflow: hidden;
}

.faq-question {
    padding: 1rem;
    background: #f8fafc;
    cursor: pointer;
    font-weight: 500;
    user-select: none;
}

.faq-answer {
    padding: 1rem;
    display: none;
}

.faq-item.active .faq-answer {
    display: block;
}

/* Checkout */
.checkout-steps {
    display: flex;
    justify-content: center;
    margin: 2rem 0;
    gap: 2rem;
}

.step {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    background: #f3f4f6;
    color: #6b7280;
}

.step.active {
    background: #6366f1;
    color: white;
}

.checkout-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.checkout-form,
.checkout-summary {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid #e5e7eb;
}

.summary-total {
    font-size: 1.25rem;
    font-weight: 700;
    color: #1f2937;
}

.payment-icons {
    display: flex;
    gap: 1rem;
    align-items: center;
    margin: 1rem 0;
}

.payment-icon {
    width: 40px;
    height: 25px;
    background: #f3f4f6;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: bold;
    color: #6b7280;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: #f9fafb;
}

.footer-contact p {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.footer-contact a {
    color: #93c5fd;
    text-decoration: none;
}

.footer-contact a:hover {
    text-decoration: underline;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #93c5fd;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 2rem;
    text-align: center;
    color: #9ca3af;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background: white;
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        padding-top: 2rem;
        transition: left 0.3s ease;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-actions {
        justify-content: center;
    }

    .section-title {
        font-size: 2rem;
    }

    .features-grid,
    .courses-grid,
    .trust-grid {
        grid-template-columns: 1fr;
    }

    .course-hero .container,
    .course-detail .container,
    .checkout-content {
        grid-template-columns: 1fr;
    }

    .course-sidebar {
        position: static;
    }

    .checkout-steps {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-actions {
        flex-direction: column;
        gap: 0.5rem;
    }

    .btn {
        width: 100%;
    }

    .course-actions {
        flex-direction: column;
    }
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.hidden {
    display: none;
}

.loading {
    opacity: 0.6;
    pointer-events: none;
}