/* ============================================================
   GOOGLE LANGUAGE EXPLORER STYLE
   Ультра-минималистичный тёмный дизайн
   ============================================================ */

/* Landing page - по умолчанию показан */
.landing-page {
    position: relative;
    z-index: 100;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: #000;
}

/* Когда landing скрыт через JS */
.landing-page.hidden {
    display: none !important;
}

/* Скрываем AI тьютор на landing page (до входа) */
.landing-page:not(.hidden) ~ .ai-tutor-btn {
    display: none !important;
}

/* ============================================================
   НАВИГАЦИЯ
   ============================================================ */
.google-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 24px 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: transparent;
    transition: all 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.google-nav.scrolled {
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(30px);
    -webkit-backdrop-filter: blur(30px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.google-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: #fff;
    transition: opacity 0.3s ease;
}

.google-logo:hover {
    opacity: 0.8;
}

.logo-icon {
    font-size: 28px;
}

.logo-text {
    font-size: 1.1rem;
    font-weight: 500;
    letter-spacing: -0.02em;
}

.google-nav-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.google-btn {
    padding: 12px 28px;
    border-radius: 100px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background: transparent;
    color: #fff;
}

.google-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.35);
    transform: translateY(-2px);
}

.google-btn-text {
    background: transparent;
    color: rgba(255, 255, 255, 0.75);
    border: none;
}

.google-btn-text:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.06);
}

.google-btn-filled {
    background: #fff;
    color: #000;
    border-color: #fff;
}

.google-btn-filled:hover {
    background: rgba(255, 255, 255, 0.92);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(255, 255, 255, 0.12);
}

.google-btn-large {
    padding: 18px 40px;
    font-size: 1rem;
    font-weight: 500;
    background: transparent;
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.25);
    border-radius: 100px;
    position: relative;
    overflow: hidden;
}

.google-btn-large::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.05) 0%, 
        transparent 50%);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.google-btn-large:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.4);
    transform: translateY(-3px);
    box-shadow: 
        0 15px 40px rgba(0, 0, 0, 0.3),
        0 0 0 1px rgba(255, 255, 255, 0.1) inset;
}

.google-btn-large:hover::before {
    opacity: 1;
}

.google-btn-large svg {
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.google-btn-large:hover svg {
    transform: translateX(4px);
}

/* ============================================================
   HERO СЕКЦИЯ - МИНИМАЛИЗМ
   ============================================================ */
.google-hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 120px 48px 80px;
    text-align: center;
    background: #000;
    position: relative;
    overflow: hidden;
}

/* Тонкое фоновое свечение */
.google-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 150%;
    height: 60%;
    background: radial-gradient(ellipse 50% 80% at 50% 0%, 
        rgba(80, 80, 120, 0.12) 0%, 
        transparent 70%);
    pointer-events: none;
}

.google-hero::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 200px;
    background: linear-gradient(to top, #000 0%, transparent 100%);
    pointer-events: none;
}

.google-hero-content {
    max-width: 850px;
    position: relative;
    z-index: 1;
}

.google-hero-title {
    font-size: clamp(2.8rem, 7vw, 4.5rem);
    font-weight: 300;
    letter-spacing: -0.02em;
    line-height: 1.15;
    color: #fff;
    margin-bottom: 28px;
    opacity: 0.95;
}

.google-hero-subtitle {
    font-size: 1.15rem;
    color: rgba(255, 255, 255, 0.55);
    line-height: 1.75;
    max-width: 580px;
    margin: 0 auto 48px;
    font-weight: 400;
    letter-spacing: 0.01em;
}

.google-hero-buttons {
    margin-bottom: 100px;
}

/* ============================================================
   СТАТИСТИКА - МИНИМАЛИСТИЧНАЯ
   ============================================================ */
.google-stats-section {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding-top: 80px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    position: relative;
    z-index: 1;
}

.google-stats-label {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.35);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    margin-bottom: 40px;
    font-weight: 400;
}

.google-stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 48px;
}

.google-stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.google-stat-number {
    font-size: clamp(2.2rem, 4vw, 3.5rem);
    font-weight: 300;
    color: rgba(255, 255, 255, 0.9);
    letter-spacing: -0.02em;
}

.google-stat-label {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.4);
    font-weight: 400;
}

/* ============================================================
   ВИЗУАЛЬНАЯ СЕКЦИЯ С КАРТОЧКАМИ СПЕЦИАЛЬНОСТЕЙ
   ============================================================ */
.google-visual-section {
    min-height: 50vh;
    padding: 100px 48px;
    background: #000;
    position: relative;
    overflow: hidden;
}

.google-visual-bg {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.visual-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(120px);
    animation: visual-float 30s ease-in-out infinite;
    opacity: 0.7;
}

.visual-orb-1 {
    width: 450px;
    height: 450px;
    background: radial-gradient(circle, rgba(70, 70, 120, 0.15) 0%, transparent 70%);
    top: 5%;
    left: 5%;
}

.visual-orb-2 {
    width: 350px;
    height: 350px;
    background: radial-gradient(circle, rgba(100, 80, 140, 0.12) 0%, transparent 70%);
    bottom: 15%;
    right: 15%;
    animation-delay: -10s;
}

.visual-orb-3 {
    width: 280px;
    height: 280px;
    background: radial-gradient(circle, rgba(60, 100, 120, 0.1) 0%, transparent 70%);
    top: 45%;
    left: 45%;
    animation-delay: -20s;
}

@keyframes visual-float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(40px, -40px) scale(1.05); }
    66% { transform: translate(-30px, 30px) scale(0.95); }
}

.google-visual-content {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
    max-width: 1100px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.specialty-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 20px;
    padding: 36px 44px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
    transition: all 0.5s cubic-bezier(0.16, 1, 0.3, 1);
    cursor: pointer;
    opacity: 0;
    transform: translateY(30px);
    animation: card-appear 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
    animation-delay: calc(var(--delay, 0) * 0.15s);
    position: relative;
    overflow: hidden;
}

.specialty-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 0%, 
        rgba(255, 255, 255, 0.03) 0%, 
        transparent 60%);
    opacity: 0;
    transition: opacity 0.5s ease;
}

.specialty-card:hover {
    background: rgba(255, 255, 255, 0.04);
    border-color: rgba(255, 255, 255, 0.12);
    transform: translateY(-6px);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3);
}

.specialty-card:hover::before {
    opacity: 1;
}

@keyframes card-appear {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.specialty-icon {
    font-size: 3rem;
    margin-bottom: 6px;
    transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.specialty-card:hover .specialty-icon {
    transform: scale(1.1);
}

.specialty-name {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.7);
    font-weight: 500;
    letter-spacing: 0.01em;
}

/* ============================================================
   FEATURES СЕКЦИЯ - ЧИСТЫЙ МИНИМАЛИЗМ
   ============================================================ */
.google-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
    padding: 100px 48px;
    max-width: 1100px;
    margin: 0 auto;
    background: #000;
}

.google-feature-item {
    padding: 44px;
    border-radius: 24px;
    background: rgba(255, 255, 255, 0.015);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: all 0.5s cubic-bezier(0.16, 1, 0.3, 1);
    position: relative;
    overflow: hidden;
}

.google-feature-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        rgba(255, 255, 255, 0.08) 50%, 
        transparent 100%);
}

.google-feature-item:hover {
    background: rgba(255, 255, 255, 0.03);
    border-color: rgba(255, 255, 255, 0.08);
    transform: translateY(-6px);
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.25);
}

.google-feature-icon {
    font-size: 2.5rem;
    margin-bottom: 24px;
    display: inline-block;
    transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.google-feature-item:hover .google-feature-icon {
    transform: scale(1.1);
}

.google-feature-item h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 14px;
}

.google-feature-item p {
    font-size: 0.92rem;
    color: rgba(255, 255, 255, 0.45);
    line-height: 1.7;
}

/* ============================================================
   АДАПТИВНОСТЬ
   ============================================================ */
@media (max-width: 1024px) {
    .google-stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 36px;
    }
    
    .google-features {
        grid-template-columns: 1fr;
        gap: 20px;
    }
}

@media (max-width: 768px) {
    .google-nav {
        padding: 18px 24px;
    }
    
    .logo-text {
        display: none;
    }
    
    .google-hero {
        padding: 100px 24px 60px;
    }
    
    .google-hero-title {
        font-size: 2.2rem;
        font-weight: 400;
    }
    
    .google-hero-subtitle {
        font-size: 1rem;
        line-height: 1.7;
    }
    
    .google-btn-large {
        padding: 16px 32px;
        font-size: 0.95rem;
    }
    
    .google-stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 28px;
    }
    
    .google-stat-number {
        font-size: 1.8rem;
    }
    
    .google-visual-section,
    .google-features {
        padding: 60px 24px;
    }
    
    .specialty-card {
        padding: 28px 36px;
    }
    
    .google-feature-item {
        padding: 32px;
    }
}

@media (max-width: 480px) {
    .google-nav {
        padding: 14px 16px;
    }
    
    .google-btn {
        padding: 10px 20px;
        font-size: 0.85rem;
    }
    
    .google-hero {
        padding: 90px 18px 50px;
    }
    
    .google-hero-title {
        font-size: 1.75rem;
        margin-bottom: 20px;
    }
    
    .google-hero-subtitle {
        font-size: 0.95rem;
        margin-bottom: 36px;
        line-height: 1.65;
    }
    
    .google-btn-large {
        padding: 14px 28px;
        font-size: 0.9rem;
    }
    
    .google-hero-buttons {
        margin-bottom: 70px;
    }
    
    .google-stats-section {
        padding-top: 50px;
    }
    
    .google-stats-label {
        font-size: 0.7rem;
        margin-bottom: 28px;
    }
    
    .google-stats-grid {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }
    
    .google-stat-number {
        font-size: 1.4rem;
    }
    
    .google-stat-label {
        font-size: 0.75rem;
    }
    
    .google-visual-section,
    .google-features {
        padding: 50px 18px;
    }
    
    .google-visual-content {
        gap: 12px;
    }
    
    .specialty-card {
        padding: 20px 24px;
        flex: 1 1 calc(50% - 12px);
        border-radius: 14px;
        gap: 10px;
    }
    
    .specialty-icon {
        font-size: 2rem;
        margin-bottom: 2px;
    }
    
    .specialty-name {
        font-size: 0.8rem;
    }
    
    .google-feature-item {
        padding: 26px;
        border-radius: 18px;
    }
    
    .google-feature-icon {
        font-size: 2rem;
        margin-bottom: 18px;
    }
    
    .google-feature-item h3 {
        font-size: 1.05rem;
        margin-bottom: 10px;
    }
    
    .google-feature-item p {
        font-size: 0.85rem;
    }
}

/* Очень маленькие экраны */
@media (max-width: 360px) {
    .google-nav {
        padding: 12px 14px;
    }
    
    .google-btn {
        padding: 8px 16px;
        font-size: 0.8rem;
    }
    
    .google-hero {
        padding: 85px 14px 45px;
    }
    
    .google-hero-title {
        font-size: 1.5rem;
    }
    
    .google-hero-subtitle {
        font-size: 0.9rem;
    }
    
    .google-btn-large {
        padding: 12px 24px;
        font-size: 0.85rem;
    }
    
    .google-stats-grid {
        gap: 12px;
    }
    
    .google-stat-number {
        font-size: 1.25rem;
    }
    
    .specialty-card {
        padding: 16px 20px;
    }
    
    .specialty-icon {
        font-size: 1.8rem;
    }
    
    .google-feature-item {
        padding: 22px;
    }
}

/* ============================================================
   АНИМАЦИИ ПОЯВЛЕНИЯ - ПЛАВНЫЕ
   ============================================================ */
.google-hero-title {
    animation: fade-up 1.2s cubic-bezier(0.16, 1, 0.3, 1) 0.15s both;
}

.google-hero-subtitle {
    animation: fade-up 1.2s cubic-bezier(0.16, 1, 0.3, 1) 0.35s both;
}

.google-hero-buttons {
    animation: fade-up 1.2s cubic-bezier(0.16, 1, 0.3, 1) 0.55s both;
}

.google-stats-section {
    animation: fade-up 1.2s cubic-bezier(0.16, 1, 0.3, 1) 0.75s both;
}

.google-feature-item:nth-child(1) {
    animation: fade-up 1s cubic-bezier(0.16, 1, 0.3, 1) 0.9s both;
}

.google-feature-item:nth-child(2) {
    animation: fade-up 1s cubic-bezier(0.16, 1, 0.3, 1) 1.05s both;
}

.google-feature-item:nth-child(3) {
    animation: fade-up 1s cubic-bezier(0.16, 1, 0.3, 1) 1.2s both;
}

@keyframes fade-up {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}