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

:root {
    --blue: #1E5BFF;
    --blue-dark: #1644C9;
    --blue-light: #E8EFFF;
    --blue-bright: #3D7BFF;
    --white: #FFFFFF;
    --bg: #F7F9FF;
    --text: #0A1A3B;
    --text-muted: #5A6B8C;
    --border: #E0E7F5;
    --shadow: 0 10px 40px rgba(30, 91, 255, 0.12);
    --shadow-hover: 0 15px 50px rgba(30, 91, 255, 0.25);
}

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Inter', sans-serif;
    color: var(--text);
    background: var(--white);
    line-height: 1.6;
    font-size: 16px;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

h1, h2, h3, h4 { line-height: 1.2; font-weight: 800; letter-spacing: -0.02em; }
h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); margin-bottom: 16px; text-align: center; }
h3 { font-size: 1.25rem; margin-bottom: 10px; }
h4 { font-size: 1rem; margin-bottom: 14px; }

a { color: var(--blue); text-decoration: none; transition: opacity 0.2s; }
a:hover { opacity: 0.75; }

.accent { color: var(--blue); }
.section-lead { text-align: center; color: var(--text-muted); max-width: 680px; margin: 0 auto 48px; font-size: 1.1rem; }

/* ================= КНОПКИ ================= */
.btn {
    display: inline-block;
    padding: 14px 28px;
    background: var(--blue);
    color: var(--white);
    border-radius: 12px;
    font-weight: 600;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: all 0.25s ease;
    text-align: center;
}
.btn:hover {
    background: var(--blue-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
    opacity: 1;
}
.btn--small { padding: 10px 20px; font-size: 0.9rem; }
.btn--ghost {
    background: transparent;
    color: var(--blue);
    border: 2px solid var(--blue);
}
.btn--ghost:hover { background: var(--blue); color: var(--white); }
.btn--light {
    background: var(--white);
    color: var(--blue);
}
.btn--light:hover { background: var(--blue-light); }
.btn--wide { width: 100%; }

/* ================= ШАПКА ================= */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
}
.header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
}
.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text);
    letter-spacing: -0.03em;
}
.logo span { color: var(--blue); }
.logo--light { color: var(--white); }
.logo--light span { color: var(--blue-bright); }
.nav { display: flex; gap: 28px; }
.nav a { color: var(--text); font-weight: 500; font-size: 0.95rem; }

/* ================= HERO ================= */
.hero {
    padding: 80px 0 100px;
    background: linear-gradient(135deg, #F0F5FF 0%, #E8EFFF 100%);
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    top: -200px; right: -200px;
    width: 600px; height: 600px;
    background: radial-gradient(circle, rgba(30, 91, 255, 0.15), transparent 70%);
    border-radius: 50%;
}
.hero .container {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 60px;
    align-items: center;
    position: relative;
}
.badge {
    display: inline-block;
    background: var(--white);
    color: var(--blue);
    padding: 8px 16px;
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
}
.hero h1 { margin-bottom: 20px; }
.hero__subtitle { font-size: 1.15rem; color: var(--text-muted); margin-bottom: 32px; max-width: 540px; }
.hero__buttons { display: flex; gap: 14px; margin-bottom: 48px; flex-wrap: wrap; }
.hero__stats {
    display: flex;
    gap: 36px;
    flex-wrap: wrap;
}
.hero__stats > div { display: flex; flex-direction: column; }
.hero__stats strong { font-size: 1.5rem; color: var(--blue); font-weight: 800; }
.hero__stats span { font-size: 0.85rem; color: var(--text-muted); }

.hero__visual {
    position: relative;
    height: 450px;
}
.card-float {
    position: absolute;
    background: var(--white);
    padding: 20px;
    border-radius: 16px;
    box-shadow: var(--shadow);
    width: 240px;
    animation: float 6s ease-in-out infinite;
}
.card-float__tag {
    display: inline-block;
    background: var(--blue-light);
    color: var(--blue);
    padding: 4px 10px;
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 12px;
}
.card-float__title { font-weight: 700; margin-bottom: 6px; }
.card-float__teacher { font-size: 0.85rem; color: var(--text-muted); }
.card-float--1 { top: 20px; left: 0; animation-delay: 0s; }
.card-float--2 { top: 160px; right: 0; animation-delay: 2s; }
.card-float--3 { bottom: 20px; left: 40px; animation-delay: 4s; }

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

/* ================= ПРОБЛЕМА ================= */
.problem { padding: 100px 0; background: var(--bg); }
.problem__grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 20px;
}
.problem__item {
    background: var(--white);
    padding: 32px 24px;
    border-radius: 20px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}
.problem__item:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    border-color: var(--blue-light);
}
.problem__icon { font-size: 2.5rem; margin-bottom: 16px; }
.problem__item p { color: var(--text-muted); font-size: 0.95rem; }

/* ================= КАК ЭТО РАБОТАЕТ ================= */
.how { padding: 100px 0; background: var(--white); }
.how__steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 20px;
}
.how__step {
    position: relative;
    background: linear-gradient(135deg, #F0F5FF 0%, #FFFFFF 100%);
    padding: 32px 24px;
    border-radius: 20px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}
.how__step:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
}
.how__number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--blue);
    color: var(--white);
    border-radius: 50%;
    font-size: 1.25rem;
    font-weight: 800;
    margin-bottom: 20px;
    box-shadow: 0 6px 20px rgba(30, 91, 255, 0.35);
}
.how__step p { color: var(--text-muted); font-size: 0.95rem; }

/* ================= ВОЗМОЖНОСТИ ================= */
.features { padding: 100px 0; background: var(--bg); }
.features__grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 20px;
}
.feature {
    background: var(--white);
    padding: 28px 24px;
    border-radius: 20px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}
.feature:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    border-color: var(--blue);
}
.feature__icon {
    font-size: 2rem;
    margin-bottom: 14px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--blue-light);
    border-radius: 14px;
}
.feature p { color: var(--text-muted); font-size: 0.95rem; }

/* ================= КОМУ ПОДОЙДЁТ ================= */
.audience { padding: 100px 0; background: var(--white); }
.audience__grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-top: 40px;
}
.audience__card {
    background: var(--bg);
    padding: 44px 36px;
    border-radius: 24px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}
.audience__card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
}
.audience__card--dark {
    background: linear-gradient(135deg, var(--blue) 0%, var(--blue-dark) 100%);
    color: var(--white);
    border: none;
}
.audience__card--dark h3,
.audience__card--dark li { color: var(--white); }
.audience__emoji {
    font-size: 3rem;
    margin-bottom: 16px;
}
.audience__card h3 { font-size: 1.5rem; margin-bottom: 20px; }
.audience__card ul {
    list-style: none;
    margin-bottom: 28px;
}
.audience__card li {
    padding: 10px 0 10px 28px;
    position: relative;
    color: var(--text);
    font-size: 1rem;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}
.audience__card--dark li { border-bottom-color: rgba(255, 255, 255, 0.15); }
.audience__card li:last-child { border-bottom: none; }
.audience__card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 10px;
    color: var(--blue);
    font-weight: 800;
}
.audience__card--dark li::before { color: var(--white); }

/* ================= FAQ ================= */
.faq { padding: 100px 0; background: var(--bg); }
.faq__list {
    max-width: 820px;
    margin: 40px auto 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.faq__item {
    background: var(--white);
    border-radius: 14px;
    border: 1px solid var(--border);
    padding: 20px 24px;
    transition: all 0.3s ease;
    overflow: hidden;
}
.faq__item:hover { border-color: var(--blue); }
.faq__item summary {
    cursor: pointer;
    font-weight: 600;
    font-size: 1.05rem;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text);
    transition: color 0.2s;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after {
    content: '+';
    font-size: 1.75rem;
    color: var(--blue);
    font-weight: 400;
    transition: transform 0.3s;
    line-height: 1;
}
.faq__item[open] summary::after { transform: rotate(45deg); }
.faq__item p {
    margin-top: 14px;
    color: var(--text-muted);
    animation: fadeIn 0.35s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ================= CTA ================= */
.cta { padding: 100px 0; background: var(--white); }
.cta__box {
    max-width: 680px;
    margin: 0 auto;
    background: linear-gradient(135deg, var(--blue) 0%, var(--blue-dark) 100%);
    color: var(--white);
    padding: 56px 48px;
    border-radius: 28px;
    text-align: center;
    box-shadow: 0 20px 60px rgba(30, 91, 255, 0.3);
}
.cta__box h2 { color: var(--white); }
.cta__box > p { color: rgba(255, 255, 255, 0.9); margin-bottom: 32px; font-size: 1.1rem; }

.cta__form {
    display: flex;
    flex-direction: column;
    gap: 14px;
    text-align: left;
}
.cta__form input[type="text"],
.cta__form input[type="email"] {
    width: 100%;
    padding: 16px 18px;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-family: inherit;
    background: var(--white);
    color: var(--text);
    transition: box-shadow 0.2s;
}
.cta__form input:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.4);
}

.checkbox {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    font-size: 0.88rem;
    color: rgba(255, 255, 255, 0.92);
    cursor: pointer;
    line-height: 1.5;
}
.checkbox input[type="checkbox"] {
    margin-top: 3px;
    width: 18px;
    height: 18px;
    flex-shrink: 0;
    accent-color: var(--white);
    cursor: pointer;
}
.checkbox a { color: var(--white); text-decoration: underline; }

.cta__form .btn {
    background: var(--white);
    color: var(--blue);
    margin-top: 8px;
}
.cta__form .btn:hover {
    background: var(--blue-light);
    color: var(--blue-dark);
}

.cta__success {
    display: none;
    background: rgba(255, 255, 255, 0.15);
    padding: 14px;
    border-radius: 10px;
    text-align: center;
    font-weight: 600;
}
.cta__success.show { display: block; }

/* ================= ФУТЕР ================= */
.footer {
    background: #0A1A3B;
    color: rgba(255, 255, 255, 0.75);
    padding: 64px 0 32px;
}
.footer__top {
    display: grid;
    grid-template-columns: 2fr 1fr 1.3fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}
.footer__col h4 {
    color: var(--white);
    margin-bottom: 18px;
    font-size: 1rem;
}
.footer__col a {
    display: block;
    color: rgba(255, 255, 255, 0.7);
    padding: 6px 0;
    font-size: 0.95rem;
    transition: color 0.2s;
}
.footer__col a:hover { color: var(--white); opacity: 1; }
.footer__col > p { font-size: 0.95rem; margin-top: 16px; max-width: 320px; }

.footer__legal {
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    padding-top: 28px;
    font-size: 0.85rem;
    line-height: 1.7;
}
.footer__legal p { margin-bottom: 12px; }
.footer__legal strong { color: var(--white); }
.footer__note { font-size: 0.82rem; color: rgba(255, 255, 255, 0.55); margin-top: 16px; }
.footer__copy {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    font-size: 0.82rem;
    color: rgba(255, 255, 255, 0.5);
}

/* ================= COOKIE ================= */
.cookie {
    position: fixed;
    bottom: 20px;
    left: 20px;
    right: 20px;
    max-width: 560px;
    margin: 0 auto;
    background: var(--white);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
    padding: 20px 24px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    gap: 20px;
    z-index: 200;
    animation: slideUp 0.5s ease;
}
.cookie.hidden { display: none; }
.cookie p { font-size: 0.9rem; flex: 1; margin: 0; }

@keyframes slideUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ================= ПЛАВНЫЕ ПОЯВЛЕНИЯ ================= */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ================= АДАПТИВ ================= */
@media (max-width: 1024px) {
    .problem__grid,
    .how__steps,
    .features__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer__top {
        grid-template-columns: 1fr 1fr;
    }
    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .hero__visual { height: 380px; max-width: 500px; margin: 0 auto; width: 100%; }
}

@media (max-width: 720px) {
    .nav { display: none; }
    .header__inner { padding: 14px 20px; }
    .hero { padding: 60px 0 80px; }
    .hero__buttons { flex-direction: column; }
    .hero__buttons .btn { width: 100%; }
    .hero__stats { gap: 20px; }
    
    .problem, .how, .features, .audience, .faq, .cta { padding: 70px 0; }
    
    .audience__grid {
        grid-template-columns: 1fr;
    }
    .audience__card { padding: 32px 24px; }
    
    .cta__box { padding: 40px 24px; }
    
    .footer__top {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    
    .cookie {
        flex-direction: column;
        text-align: center;
        gap: 12px;
        left: 10px;
        right: 10px;
        bottom: 10px;
    }
    
    h1 { font-size: 2rem; }
    h2 { font-size: 1.6rem; }
    
    .card-float { width: 200px; }
    .card-float--1 { left: 0; }
    .card-float--2 { right: 0; top: 140px; }
    .card-float--3 { left: 20px; bottom: 0; }
}

@media (max-width: 480px) {
    .problem__grid,
    .how__steps,
    .features__grid {
        grid-template-columns: 1fr;
    }
    .hero__visual { height: 340px; }
    .card-float { width: 180px; padding: 16px; }
}