/* ============================================
   EVOLUTION LANDING PAGE
   Биологический стиль + Скевоморфизм + Морская тематика
   ============================================ */

:root {
    --primary: #1a8fb8;
    --primary-dark: #156a8a;
    --primary-light: #2db3e8;
    --secondary: #2ecc71;
    --accent: #f39c12;
    --danger: #e74c3c;
    
    --ocean-deep: #0a2540;
    --ocean-mid: #1a4d6f;
    --ocean-light: #2a7ba8;
    --foam: #e8f4f8;
    --sand: #f4e4c1;
    
    --text-dark: #2c3e50;
    --text-light: #ecf0f1;
    --text-muted: #95a5a6;
    
    --gradient-ocean: linear-gradient(135deg, #0a2540 0%, #1a4d6f 50%, #2a7ba8 100%);
    --gradient-cell: linear-gradient(135deg, #2ecc71 0%, #27ae60 100%);
    --gradient-coral: linear-gradient(135deg, #ff6b6b 0%, #ee5a6f 100%);
    
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
    --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.25);
    
    --border-radius: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: var(--ocean-deep);
    overflow-x: hidden;
}

.landing-container {
    width: 100%;
    min-height: 100vh;
}

/* ============================================
   NAVIGATION
   ============================================ */

.landing-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1rem 0;
    transition: var(--transition);
    background: rgba(10, 37, 64, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.landing-nav.scrolled {
    padding: 0.5rem 0;
    background: rgba(10, 37, 64, 0.95);
    box-shadow: var(--shadow-md);
}

.nav-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-light);
    text-decoration: none;
}

.logo-icon {
    font-size: 2rem;
    filter: drop-shadow(0 0 8px rgba(46, 204, 113, 0.6));
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-link:hover {
    color: var(--primary-light);
}

.nav-link:hover::after {
    width: 100%;
}

.btn-login,
.btn-register {
    padding: 0.6rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

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

.btn-login:hover {
    background: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(26, 143, 184, 0.4);
}

.btn-register {
    color: white;
    background: var(--gradient-cell);
    border: 2px solid transparent;
    box-shadow: 0 4px 12px rgba(46, 204, 113, 0.3);
}

.btn-register:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(46, 204, 113, 0.5);
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 8rem 2rem 4rem;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-ocean);
    z-index: 0;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(46, 204, 113, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(52, 152, 219, 0.1) 0%, transparent 50%);
    animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.5; }
    50% { opacity: 1; }
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-md);
}

.badge-icon {
    font-size: 1.2rem;
}

.hero-title {
    font-size: 4rem;
    font-weight: 800;
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.2;
    text-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-description {
    font-size: 1.25rem;
    color: var(--foam);
    margin-bottom: 3rem;
    line-height: 1.8;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 4rem;
}

.btn-primary,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2.5rem;
    border-radius: 12px;
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 700;
    transition: var(--transition);
    border: 2px solid transparent;
}

.btn-primary {
    background: var(--gradient-cell);
    color: white;
    box-shadow: 0 8px 24px rgba(46, 204, 113, 0.4);
}

.btn-primary:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(46, 204, 113, 0.6);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    color: var(--text-light);
    border-color: rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-4px);
}

.btn-icon {
    font-size: 1.3rem;
}

.hero-stats {
    display: flex;
    gap: 3rem;
    justify-content: center;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-icon {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.3));
}

.stat-value {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-light);
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--foam);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Bubbles Animation */
.hero-decoration {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
    z-index: 1;
}

.bubble {
    position: absolute;
    border-radius: 50%;
    background: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
    box-shadow: inset 0 0 20px rgba(255, 255, 255, 0.2);
    animation: float 15s infinite ease-in-out;
}

.bubble-1 {
    width: 80px;
    height: 80px;
    left: 10%;
    bottom: -80px;
    animation-delay: 0s;
}

.bubble-2 {
    width: 60px;
    height: 60px;
    left: 70%;
    bottom: -60px;
    animation-delay: 3s;
}

.bubble-3 {
    width: 100px;
    height: 100px;
    left: 30%;
    bottom: -100px;
    animation-delay: 6s;
}

.bubble-4 {
    width: 50px;
    height: 50px;
    left: 85%;
    bottom: -50px;
    animation-delay: 9s;
}

@keyframes float {
    0% {
        transform: translateY(0) translateX(0) scale(1);
        opacity: 0;
    }
    10% {
        opacity: 0.6;
    }
    90% {
        opacity: 0.6;
    }
    100% {
        transform: translateY(-100vh) translateX(50px) scale(0.8);
        opacity: 0;
    }
}

/* ============================================
   SECTIONS
   ============================================ */

.about,
.features,
.authors,
.cta {
    padding: 6rem 2rem;
    position: relative;
}

.about {
    background: linear-gradient(180deg, var(--ocean-deep) 0%, var(--ocean-mid) 100%);
}

.features {
    background: var(--ocean-mid);
}

.authors {
    background: linear-gradient(180deg, var(--ocean-mid) 0%, var(--ocean-deep) 100%);
}

.section-content {
    max-width: 1200px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-badge {
    display: inline-block;
    padding: 0.5rem 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.section-title {
    font-size: 3rem;
    font-weight: 800;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--foam);
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   ABOUT CARDS
   ============================================ */

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.about-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    text-align: center;
    transition: var(--transition);
    opacity: 0;
    transform: translateY(30px);
}

.about-card.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.about-card:hover {
    transform: translateY(-8px);
    border-color: var(--primary-light);
    box-shadow: 0 12px 40px rgba(26, 143, 184, 0.3);
    background: rgba(255, 255, 255, 0.08);
}

.card-icon {
    font-size: 4rem;
    margin-bottom: 1.5rem;
    filter: drop-shadow(0 0 20px rgba(46, 204, 113, 0.5));
}

.about-card h3 {
    font-size: 1.5rem;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.about-card p {
    color: var(--foam);
    line-height: 1.8;
}

/* ============================================
   FEATURES
   ============================================ */

.features-list {
    display: flex;
    flex-direction: column;
    gap: 4rem;
}

.feature-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    opacity: 0;
    transform: translateX(-30px);
    transition: var(--transition);
}

.feature-item.animate-in {
    opacity: 1;
    transform: translateX(0);
}

.feature-reverse {
    transform: translateX(30px);
}

.feature-reverse.animate-in {
    transform: translateX(0);
}

.feature-reverse .feature-visual {
    order: 2;
}

.feature-visual {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 300px;
}

.feature-icon {
    font-size: 8rem;
    filter: drop-shadow(0 0 40px rgba(46, 204, 113, 0.6));
    animation: float-gentle 6s ease-in-out infinite;
}

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

.feature-content h3 {
    font-size: 2rem;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.feature-content p {
    font-size: 1.1rem;
    color: var(--foam);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.feature-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.feature-list li {
    color: var(--text-light);
    padding-left: 2rem;
    position: relative;
}

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

/* ============================================
   AUTHORS
   ============================================ */

.authors-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
}

.author-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    padding: 3rem 2rem;
    text-align: center;
    transition: var(--transition);
    opacity: 0;
    transform: scale(0.9);
}

.author-card.animate-in {
    opacity: 1;
    transform: scale(1);
}

.author-card:hover {
    transform: translateY(-8px) scale(1.02);
    border-color: var(--primary-light);
    box-shadow: 0 12px 40px rgba(26, 143, 184, 0.3);
}

.author-avatar {
    width: 120px;
    height: 120px;
    margin: 0 auto 1.5rem;
    border-radius: 50%;
    background: var(--gradient-cell);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 24px rgba(46, 204, 113, 0.4);
    border: 4px solid rgba(255, 255, 255, 0.2);
}

.avatar-placeholder {
    font-size: 3rem;
}

.author-name {
    font-size: 1.5rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

.author-role {
    color: var(--primary-light);
    font-weight: 600;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.9rem;
}

.author-bio {
    color: var(--foam);
    line-height: 1.8;
}

/* ============================================
   CTA SECTION
   ============================================ */

.cta {
    background: var(--gradient-ocean);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta-decoration {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    opacity: 0.1;
    pointer-events: none;
}

.dna-strand {
    width: 100%;
    height: 100%;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 20px,
        rgba(46, 204, 113, 0.3) 20px,
        rgba(46, 204, 113, 0.3) 40px
    );
    animation: dna-rotate 20s linear infinite;
}

@keyframes dna-rotate {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.cta-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
}

.cta-title {
    font-size: 3rem;
    font-weight: 800;
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.cta-description {
    font-size: 1.25rem;
    color: var(--foam);
    margin-bottom: 3rem;
    line-height: 1.8;
}

.cta-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    align-items: center;
}

.btn-cta-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1.25rem 3rem;
    background: var(--gradient-cell);
    color: white;
    text-decoration: none;
    font-size: 1.25rem;
    font-weight: 700;
    border-radius: 12px;
    box-shadow: 0 8px 24px rgba(46, 204, 113, 0.4);
    transition: var(--transition);
    border: 2px solid transparent;
}

.btn-cta-primary:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(46, 204, 113, 0.6);
}

.btn-cta-secondary {
    color: var(--text-light);
    text-decoration: none;
    font-size: 1rem;
    transition: var(--transition);
    opacity: 0.8;
}

.btn-cta-secondary:hover {
    opacity: 1;
    color: var(--primary-light);
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background: rgba(10, 37, 64, 0.95);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 4rem 2rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-section h4 {
    color: var(--text-light);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.footer-description {
    color: var(--foam);
    line-height: 1.8;
    opacity: 0.8;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-links a {
    color: var(--foam);
    text-decoration: none;
    transition: var(--transition);
    opacity: 0.8;
}

.footer-links a:hover {
    color: var(--primary-light);
    opacity: 1;
    padding-left: 0.5rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-link {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    font-size: 1.5rem;
    text-decoration: none;
    transition: var(--transition);
}

.social-link:hover {
    background: var(--primary);
    border-color: var(--primary-light);
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(26, 143, 184, 0.4);
}

.footer-bottom {
    max-width: 1200px;
    margin: 0 auto;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    color: var(--foam);
    opacity: 0.6;
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 968px) {
    .hero-title {
        font-size: 3rem;
    }
    
    .section-title {
        font-size: 2.5rem;
    }
    
    .feature-item {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .feature-reverse .feature-visual {
        order: 1;
    }
    
    .nav-links {
        gap: 1rem;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-description {
        font-size: 1.1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
        justify-content: center;
    }
    
    .nav-links {
        display: none;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .cta-title {
        font-size: 2rem;
    }
}