:root {
    /* Светлая тема */
    --bg-primary: linear-gradient(90deg, #C0C0C0 0%, #E9F7FF 100%);
    --bg-glass: rgba(255, 255, 255, 0.25);
    --bg-glass-hover: rgba(255, 255, 255, 0.35);
    --text-primary: #333;
    --text-secondary: #555;
    --accent: #4a6cf7;
    --accent-hover: #3a5ce5;
    --shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.15);
    --border: 1px solid rgba(255, 255, 255, 0.18);
}

.dark-theme {
    /* Темная тема */
    --bg-primary: linear-gradient(90deg, #192127 0%, #22006B 100%);
    --bg-glass: rgba(0, 0, 0, 0.25);
    --bg-glass-hover: rgba(0, 0, 0, 0.35);
    --text-primary: #fff;
    --text-secondary: #ccc;
    --accent: #6c8eff;
    --accent-hover: #5a7eff;
    --shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
    --border: 1px solid rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0;
}

/* Header */
header {
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: var(--bg-glass);
    border-bottom: var(--border);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
    margin-left: 50px;
}

.logo span span {
    color: var(--accent);
}

.logo img {
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

/* Desktop Navigation */
.desktop-nav {
    display: flex;
    flex: 1;
    justify-content: center;
}

.desktop-nav ul {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 30px;
    margin: 0;
    padding: 0;
}

.desktop-nav ul li {
    margin: 0;
}

.desktop-nav ul li a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    position: relative;
    padding: 8px 0;
    white-space: nowrap;
}

.desktop-nav ul li a:hover {
    color: var(--accent);
}

.desktop-nav ul li a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 0;
    background-color: var(--accent);
    transition: width 0.3s;
}

.desktop-nav ul li a:hover::after {
    width: 100%;
}

/* Переключатель темы */
.theme-toggle {
    background: var(--bg-glass);
    border: var(--border);
    border-radius: 50px;
    width: 60px;
    height: 30px;
    cursor: pointer;
    display: flex;
    align-items: center;
    padding: 0 5px;
    position: relative;
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    flex-shrink: 0;
}

.theme-toggle:hover {
    background: var(--bg-glass-hover);
}

.toggle-slider {
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: var(--accent);
    position: absolute;
    left: 4px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 12px;
}

.dark-theme .toggle-slider {
    left: calc(100% - 26px);
    background: var(--accent);
}

.theme-icon {
    position: absolute;
    font-size: 14px;
    transition: all 0.3s ease;
    z-index: 2;
}

.sun {
    left: 8px;
    color: #000;
    opacity: 1;
}

.moon {
    right: 8px;
    color: #fff;
    opacity: 0;
}

.dark-theme .sun {
    opacity: 0;
    color: #fff;
}

.dark-theme .moon {
    opacity: 1;
    color: #000;
}

/* Hero Section */
.hero {
    padding: 100px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero h2 {
    font-size: 1.8rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    font-weight: 400;
}

/* Кубик изображение главное */
.kebe-main {
    width: 200px;
    height: 200px;
    margin: 0 auto;
    display: block;
    animation: pure-float 3s ease-in-out infinite;
    position: relative;
    z-index: 1;
}

/* Чистая анимация парения без тени */
@keyframes pure-float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* Steps Section */
.step {
    padding: 100px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 60px;
}

.section-title h2 {
    font-size: 2.5rem;
    line-height: 2.5rem;
    margin-bottom: 15px;
}

.section-title p {
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.step-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: start;
    margin-bottom: 50px;
    /* Убрали Glassmorphism */
    background: transparent;
    backdrop-filter: none;
    padding: 0;
    border-radius: 0;
    border: none;
    box-shadow: none;
}

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

.step-image {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 20px;
    overflow: visible;
}

/* Контейнер для частиц */
.particles-container {
    position: absolute;
    top: -50px;
    left: -50px;
    width: calc(100% + 100px);
    height: calc(100% + 100px);
    border-radius: 20px;
    overflow: visible;
    z-index: 1;
}

/* Стили для частиц */
.particle {
    position: absolute;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), rgba(106, 17, 203, 0.7));
    animation: float-particle 25s infinite linear, pulse-particle 4s infinite ease-in-out;
    opacity: 0.7;
    filter: blur(0.5px);
}

/* Разные размеры и цвета частиц */
.particle:nth-child(1) { width: 8px; height: 8px; animation-delay: 0s; animation-duration: 30s; background: linear-gradient(135deg, var(--accent), #ff6b6b); }
.particle:nth-child(2) { width: 6px; height: 6px; animation-delay: 2s; animation-duration: 35s; background: linear-gradient(135deg, var(--accent), #4ecdc4); }
.particle:nth-child(3) { width: 10px; height: 10px; animation-delay: 4s; animation-duration: 28s; background: linear-gradient(135deg, var(--accent), #45b7d1); }
.particle:nth-child(4) { width: 7px; height: 7px; animation-delay: 6s; animation-duration: 32s; background: linear-gradient(135deg, var(--accent), #96ceb4); }
.particle:nth-child(5) { width: 5px; height: 5px; animation-delay: 8s; animation-duration: 40s; background: linear-gradient(135deg, var(--accent), #feca57); }
.particle:nth-child(6) { width: 9px; height: 9px; animation-delay: 10s; animation-duration: 27s; background: linear-gradient(135deg, var(--accent), #ff9ff3); }
.particle:nth-child(7) { width: 6px; height: 6px; animation-delay: 12s; animation-duration: 38s; background: linear-gradient(135deg, var(--accent), #54a0ff); }
.particle:nth-child(8) { width: 8px; height: 8px; animation-delay: 14s; animation-duration: 29s; background: linear-gradient(135deg, var(--accent), #5f27cd); }
.particle:nth-child(9) { width: 7px; height: 7px; animation-delay: 16s; animation-duration: 34s; background: linear-gradient(135deg, var(--accent), #00d2d3); }
.particle:nth-child(10) { width: 5px; height: 5px; animation-delay: 18s; animation-duration: 36s; background: linear-gradient(135deg, var(--accent), #ff9f43); }
.particle:nth-child(11) { width: 10px; height: 10px; animation-delay: 20s; animation-duration: 26s; background: linear-gradient(135deg, var(--accent), #ee5a24); }
.particle:nth-child(12) { width: 6px; height: 6px; animation-delay: 22s; animation-duration: 39s; background: linear-gradient(135deg, var(--accent), #c44569); }
.particle:nth-child(13) { width: 8px; height: 8px; animation-delay: 24s; animation-duration: 31s; background: linear-gradient(135deg, var(--accent), #786fa6); }
.particle:nth-child(14) { width: 7px; height: 7px; animation-delay: 26s; animation-duration: 33s; background: linear-gradient(135deg, var(--accent), #f368e0); }
.particle:nth-child(15) { width: 9px; height: 9px; animation-delay: 28s; animation-duration: 37s; background: linear-gradient(135deg, var(--accent), #ffb142); }

/* Случайное позиционирование частиц */
.particle:nth-child(1) { top: 5%; left: 5%; }
.particle:nth-child(2) { top: 70%; left: 90%; }
.particle:nth-child(3) { top: 20%; left: 30%; }
.particle:nth-child(4) { top: 85%; left: 0%; }
.particle:nth-child(5) { top: 10%; left: 60%; }
.particle:nth-child(6) { top: 75%; left: 20%; }
.particle:nth-child(7) { top: 40%; left: 95%; }
.particle:nth-child(8) { top: 95%; left: 50%; }
.particle:nth-child(9) { top: 10%; left: 40%; }
.particle:nth-child(10) { top: 55%; left: 5%; }
.particle:nth-child(11) { top: 90%; left: 80%; }
.particle:nth-child(12) { top: 20%; left: 15%; }
.particle:nth-child(13) { top: 65%; left: 35%; }
.particle:nth-child(14) { top: 30%; left: 65%; }
.particle:nth-child(15) { top: 80%; left: -5%; }

/* Анимация движения частиц */
@keyframes float-particle {
    0% {
        transform: translate(0, 0) rotate(0deg) scale(1);
        opacity: 0.6;
    }
    10% {
        transform: translate(60px, -35px) rotate(36deg) scale(1.1);
        opacity: 0.8;
    }
    20% {
        transform: translate(-40px, 55px) rotate(72deg) scale(0.9);
        opacity: 0.5;
    }
    30% {
        transform: translate(80px, 25px) rotate(108deg) scale(1.2);
        opacity: 0.9;
    }
    40% {
        transform: translate(-30px, -45px) rotate(144deg) scale(0.8);
        opacity: 0.4;
    }
    50% {
        transform: translate(45px, 60px) rotate(180deg) scale(1.1);
        opacity: 0.7;
    }
    60% {
        transform: translate(-55px, 30px) rotate(216deg) scale(0.9);
        opacity: 0.6;
    }
    70% {
        transform: translate(35px, -50px) rotate(252deg) scale(1.3);
        opacity: 0.8;
    }
    80% {
        transform: translate(-60px, 40px) rotate(288deg) scale(0.7);
        opacity: 0.5;
    }
    90% {
        transform: translate(25px, 35px) rotate(324deg) scale(1.1);
        opacity: 0.9;
    }
    100% {
        transform: translate(0, 0) rotate(360deg) scale(1);
        opacity: 0.6;
    }
}

/* Анимация пульсации */
@keyframes pulse-particle {
    0%, 100% {
        filter: blur(0.5px) brightness(1);
    }
    50% {
        filter: blur(1px) brightness(1.3);
    }
}

/* Стили для системы вкладок */
.step-image-content {
    width: 100%;
    background: var(--bg-glass);
    backdrop-filter: blur(3px);
    border-radius: 20px;
    border: var(--border);
    box-shadow: var(--shadow);
    overflow: hidden;
    position: relative;
    z-index: 2;
}

.tabs-container {
    width: 100%;
}

.tabs-header {
    display: flex;
    backdrop-filter: blur(10px);
    border-bottom: var(--border);
}

.tab-btn {
    flex: 1;
    background: none;
    border: none;
    padding: 15px 20px;
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.tab-btn::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 3px;
    background: var(--accent);
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

.tab-btn:hover {
    color: var(--text-primary);
    background: var(--bg-glass-hover);
}

.tab-btn.active {
    color: var(--accent);
}

.tab-btn.active::after {
    width: 80%;
}

.tabs-content {
    padding: 30px;
}

.tab-pane {
    display: none;
    animation: fadeIn 0.5s ease;
}

.tab-pane.active {
    display: block;
}

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

/* Стили для изображений в табах (без Glassmorphism и border) */
.tab-pane .step-img {
    width: 100%;
    max-width: 100%;
    height: auto;
}

.tab-pane .image-caption {
    margin-top: 15px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-style: italic;
    text-align: center;
}

.step-navigation {
    display: flex;
    justify-content: center;
    gap: 20px;
    /* Убрали Glassmorphism */
    background: transparent;
    backdrop-filter: none;
    padding: 25px 0;
    border-radius: 0;
    border: none;
    box-shadow: none;
}

.btn {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 15px 0 rgba(74, 108, 247, 0.3);
}

.btn:hover {
    background: var(--accent-hover);
    transform: translateY(-3px);
    box-shadow: 0 6px 20px 0 rgba(74, 108, 247, 0.4);
}

.btn-secondary {
    background: transparent;
    color: var(--accent);
    border: 2px solid var(--accent);
    box-shadow: none;
}

.btn-secondary:hover {
    background: var(--accent);
    color: white;
}

/* Footer */
footer {
    background: var(--bg-glass);
    backdrop-filter: blur(10px);
    padding: 50px 0 20px;
    border-top: var(--border);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h3 {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-column ul {
    list-style: none;
}

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

.footer-column ul li a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-column ul li a:hover {
    color: var(--accent);
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: var(--border);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Прогресс-бар */
.progress-container {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    padding: 15px 20px;
    background: var(--bg-glass);
    backdrop-filter: blur(15px);
    border-bottom: var(--border);
    box-shadow: var(--shadow);
    z-index: 90;
    display: none;
}

.progress-container.active {
    display: block;
}

/* Скрываем прогресс-бар на мобильных устройствах */
@media (max-width: 768px) {
    .progress-container {
        display: none !important; /* Принудительно скрываем на мобильных */
    }
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--bg-glass);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), #00ff88);
    border-radius: 3px;
    width: 0%;
    transition: width 0.5s ease;
    position: relative;
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.progress-steps {
    display: flex;
    justify-content: space-between;
    font-size: 0.7rem;
}

.progress-step {
    color: var(--text-secondary);
    transition: all 0.3s ease;
    text-align: center;
    flex: 1;
    position: relative;
    padding-top: 20px;
}

.progress-step::before {
    content: '';
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 8px;
    height: 8px;
    background: var(--bg-glass);
    border: 2px solid var(--text-secondary);
    border-radius: 50%;
    transition: all 0.3s ease;
}

.progress-step.active {
    color: var(--accent);
    font-weight: 600;
}

.progress-step.active::before {
    background: var(--accent);
    border-color: var(--accent);
    box-shadow: 0 0 10px var(--accent);
}

.progress-step.completed::before {
    background: #00ff88;
    border-color: #00ff88;
}

/* Мобильное меню */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-primary);
    cursor: pointer;
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    z-index: 101;
}

.mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 98;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

.mobile-nav {
    position: fixed;
    top: 0;
    left: -66.66%;
    width: 66.66%;
    height: 100%;
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    z-index: 99;
    padding: 80px 30px 30px;
    transition: left 0.3s ease;
    box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
    border-right: var(--border);
}

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

.mobile-nav ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.mobile-nav ul li {
    margin-bottom: 0;
}

.mobile-nav ul li a {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 18px;
    font-weight: 500;
    display: block;
    padding: 12px 15px;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.mobile-nav ul li a:hover {
    background: var(--bg-glass-hover);
    color: var(--accent);
}

/* Responsive */
@media (max-width: 1024px) {
    .step-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .step-image {
        order: -1;
    }
    
    .desktop-nav ul {
        gap: 20px;
    }
}

@media (max-width: 768px) {
    .header-content {
        justify-content: space-between;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .desktop-nav {
        display: none;
    }
    
    .theme-toggle {
        position: static;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero h2 {
        font-size: 1.5rem;
    }
    
    .logo {
        position: static;
        transform: none;
        margin: auto;
    }
    
    .kebe-main {
        width: 150px;
        height: 150px;
    }
    
    .progress-container {
        top: 70px;
        padding: 10px 15px;
    }
    
    .progress-steps {
        font-size: 0.6rem;
    }
    
    .progress-step {
        padding-top: 15px;
    }
    
    .progress-step::before {
        top: -12px;
        width: 6px;
        height: 6px;
    }
    
    .tabs-header {
        flex-direction: column;
    }
    
    .tab-btn {
        padding: 12px 15px;
        text-align: center;
        border-bottom: var(--border);
    }
    
    .tab-btn:last-child {
        border-bottom: none;
    }
    
    .tab-btn::after {
        display: none;
    }
    
    .tabs-content {
        padding: 20px;
    }
    
    .particles-container {
        top: -20px;
        left: -20px;
        width: calc(100% + 40px);
        height: calc(100% + 40px);
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 20px;
        margin: auto;
    }
    
    .logo img {
        width: 35px;
        height: 35px;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero h2 {
        font-size: 1.2rem;
    }
    
    .kebe-main {
        width: 120px;
        height: 120px;
    }
    
    .step-navigation {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 250px;
        text-align: center;
    }
}