:root {
    --color-primary: #667eea;
    --color-primary-dark: #5568d3;
    --color-secondary: #764ba2;
    --color-accent: #f5576c;
    --color-success: #43e97b;
    
    --color-bg: #ffffff;
    --color-bg-secondary: #f8f9fa;
    --color-bg-tertiary: #e9ecef;
    --color-surface: #ffffff;
    
    --color-text: #1a1a1a;
    --color-text-secondary: #6c757d;
    --color-text-muted: #adb5bd;
    
    --color-border: #dee2e6;
    --color-shadow: rgba(0, 0, 0, 0.1);
    
    --font-display: 'Playfair Display', serif;
    --font-body: 'Manrope', sans-serif;
    
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.6;
    overflow-x: hidden;
}

.page {
    position: relative;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-fast);
}

button, input, select, textarea {
    font-family: inherit;
}

h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 900;
    line-height: 1.2;
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: var(--space-xl);
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-lg);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    transition: all var(--transition-base);
    border: none;
    cursor: pointer;
    text-align: center;
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
}

.btn--primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
}

.btn--outline {
    border: 2px solid var(--color-primary);
    color: var(--color-primary);
    background: transparent;
}

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

.btn--small {
    padding: var(--space-xs) var(--space-md);
    font-size: 0.875rem;
}

.btn--header {
    padding: 0.625rem 1.5rem;
}

/* Header */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.9);
    border-bottom: 1px solid var(--color-border);
    backdrop-filter: blur(10px);
}

.header__content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--color-primary);
}

.logo__icon {
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.header__burger-checkbox {
    display: none;
}

.header__burger {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: var(--space-xs);
    cursor: pointer;
}

.header__burger span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    transition: all var(--transition-base);
}

.header__burger-checkbox:checked ~ .header__burger span:nth-child(1) {
    transform: rotate(45deg) translateY(6px);
}

.header__burger-checkbox:checked ~ .header__burger span:nth-child(2) {
    opacity: 0;
}

.header__burger-checkbox:checked ~ .header__burger span:nth-child(3) {
    transform: rotate(-45deg) translateY(-6px);
}

.nav {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.nav__list {
    display: flex;
    list-style: none;
    gap: var(--space-lg);
}

.nav__link {
    position: relative;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.nav__link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width var(--transition-base);
}

.nav__link:hover {
    color: var(--color-primary);
}

.nav__link:hover::after {
    width: 100%;
}

/* Hero Slider */
.hero {
    padding: var(--space-xl) 0;
}

.slider {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-xl);
    background: var(--color-bg-secondary);
}

.slider__input {
    display: none;
}

.slider__track {
    display: flex;
    transition: transform var(--transition-slow);
}

.slider__slide {
    min-width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    padding: var(--space-2xl);
}

#slide1:checked ~ .slider__track {
    transform: translateX(0%);
}

#slide2:checked ~ .slider__track {
    transform: translateX(-100%);
}

#slide3:checked ~ .slider__track {
    transform: translateX(-200%);
}

#slide4:checked ~ .slider__track {
    transform: translateX(-300%);
}

.slider__content {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: var(--space-md);
}

.slider__title {
    font-size: clamp(2.5rem, 6vw, 4rem);
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.slider__subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
}

.slider__image {
    border-radius: var(--radius-lg);
    min-height: 300px;
}

.slider__image--1 {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.slider__image--2 {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

.slider__image--3 {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

.slider__image--4 {
    background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
}

.slider__indicators {
    display: flex;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-lg);
}

.slider__indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--color-border);
    transition: all var(--transition-base);
    cursor: pointer;
}

#slide1:checked ~ .slider__indicators label:nth-child(1),
#slide2:checked ~ .slider__indicators label:nth-child(2),
#slide3:checked ~ .slider__indicators label:nth-child(3),
#slide4:checked ~ .slider__indicators label:nth-child(4) {
    background: var(--color-primary);
    width: 32px;
    border-radius: 6px;
}

/* Search Section */
.search {
    padding: var(--space-xl) 0;
    background: var(--color-bg-secondary);
}

.search__wrapper {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.search__title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    margin-bottom: var(--space-lg);
}

.search__form {
    display: flex;
    gap: var(--space-sm);
    background: var(--color-surface);
    padding: var(--space-xs);
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 20px var(--color-shadow);
}

.search__input {
    flex: 1;
    padding: var(--space-md);
    border: none;
    background: transparent;
    font-size: 1rem;
    color: var(--color-text);
    outline: none;
}

.search__input::placeholder {
    color: var(--color-text-muted);
}

/* Features */
.features {
    padding: var(--space-2xl) 0;
}

.features__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
}

.feature-card {
    text-align: center;
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px var(--color-shadow);
    border-color: var(--color-primary);
}

.feature-card__icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-md);
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
}

.feature-card__title {
    font-size: 1.25rem;
    margin-bottom: var(--space-sm);
}

.feature-card__text {
    color: var(--color-text-secondary);
}

/* Courses */
.courses {
    padding: var(--space-2xl) 0;
}

.courses__grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.course-card {
    display: flex;
    flex-direction: column;
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--color-border);
    transition: all var(--transition-base);
}

.course-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 40px var(--color-shadow);
}

.course-card__image {
    position: relative;
    height: 200px;
    background-size: cover;
    background-position: center;
}

.course-card__image--1 {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.course-card__image--2 {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

.course-card__image--3 {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

.course-card__image--4 {
    background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
}

.course-card__image--5 {
    background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
}

.course-card__image--6 {
    background: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
}

.course-card__badge {
    position: absolute;
    top: var(--space-sm);
    right: var(--space-sm);
    padding: var(--space-xs) var(--space-md);
    background: var(--color-accent);
    color: white;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
}

.course-card__content {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: var(--space-md);
}

.course-card__title {
    font-size: 1.125rem;
    margin-bottom: var(--space-xs);
}

.course-card__author {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    margin-bottom: var(--space-sm);
}

.course-card__rating {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    margin-bottom: var(--space-md);
}

.stars {
    display: flex;
    gap: 2px;
}

.star {
    color: var(--color-border);
    font-size: 1rem;
}

.star--filled {
    color: #ffc107;
}

.course-card__reviews {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
}

.course-card__footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: auto;
    padding-top: var(--space-md);
    border-top: 1px solid var(--color-border);
}

.course-card__price {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.course-card__price-old {
    color: var(--color-text-muted);
    text-decoration: line-through;
    font-size: 0.875rem;
}

.course-card__price-new {
    color: var(--color-primary);
    font-size: 1.25rem;
    font-weight: 700;
}

/* Partners */
.partners {
    padding: var(--space-2xl) 0;
    background: var(--color-bg-secondary);
}

.partners__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-lg);
}

.partner-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-lg);
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    color: var(--color-text-secondary);
    transition: all var(--transition-base);
}

.partner-logo:hover {
    transform: scale(1.05);
    color: var(--color-primary);
}

/* Footer */
.footer {
    background: var(--color-bg-tertiary);
    padding: var(--space-2xl) 0 var(--space-lg);
    margin-top: var(--space-2xl);
}

.footer__content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-xl);
    margin-bottom: var(--space-xl);
}

.footer__title {
    font-size: 1.125rem;
    margin-bottom: var(--space-md);
}

.footer__list {
    list-style: none;
}

.footer__list li {
    margin-bottom: var(--space-sm);
}

.footer__list a {
    color: var(--color-text-secondary);
}

.footer__list a:hover {
    color: var(--color-primary);
}

.footer__bottom {
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border);
    text-align: center;
    color: var(--color-text-secondary);
}

/* Floating Animation */
.floating-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

.floating-animation__circle {
    position: absolute;
    border-radius: 50%;
    opacity: 0.1;
    animation: float 20s infinite ease-in-out;
}

.floating-animation__circle--1 {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    top: 10%;
    left: -10%;
    animation-duration: 25s;
}

.floating-animation__circle--2 {
    width: 200px;
    height: 200px;
    background: linear-gradient(135deg, var(--color-accent), var(--color-success));
    top: 50%;
    right: -5%;
    animation-duration: 30s;
    animation-delay: 5s;
}

.floating-animation__circle--3 {
    width: 250px;
    height: 250px;
    background: linear-gradient(135deg, var(--color-success), var(--color-primary));
    bottom: 10%;
    left: 50%;
    animation-duration: 35s;
    animation-delay: 10s;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) scale(1);
    }
    33% {
        transform: translate(50px, -50px) scale(1.1);
    }
    66% {
        transform: translate(-30px, 30px) scale(0.9);
    }
}

/* Responsive */
@media (max-width: 768px) {
    .header__burger {
        display: flex;
    }
    
    .nav {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--color-surface);
        padding: var(--space-lg);
        border-top: 1px solid var(--color-border);
        transform: translateY(-120%);
        transition: transform var(--transition-base);
        box-shadow: 0 4px 20px var(--color-shadow);
    }
    
    .header__burger-checkbox:checked ~ .nav {
        transform: translateY(0);
    }
    
    .nav__list {
        flex-direction: column;
        width: 100%;
    }
    
    .slider__slide {
        grid-template-columns: 1fr;
        padding: var(--space-lg);
    }
    
    .slider__image {
        order: -1;
        min-height: 200px;
    }
    
    .courses__grid {
        grid-template-columns: 1fr;
    }
    
    .footer__content {
        grid-template-columns: 1fr;
    }
}

@media (min-width: 769px) and (max-width: 1200px) {
    .slider__slide {
        padding: var(--space-xl);
    }
    
    .courses__grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1201px) {
    .courses__grid {
        grid-template-columns: repeat(3, 1fr);
    }
}