:root {
    color-scheme: light;
    --bg: #f8fafc;
    --text: #0f172a;
    --muted: #526173;
    --primary: #1e3a8a;
    --primary-dark: #152d6b;
    --accent: #14b8a6;
    --accent-dark: #0f766e;
    --card: #ffffff;
    --border: #e2e8f0;
    --shadow: 0 24px 48px rgba(15, 23, 42, 0.08);
}

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

body {
    font-family: 'Noto Sans', system-ui, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
}

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

a {
    color: inherit;
    text-decoration: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.25rem;
}

.section {
    padding: 5rem 0;
}

.section-head {
    text-align: center;
    margin-bottom: 3rem;
}

.section-head h2 {
    font-family: 'Noto Serif', serif;
    font-size: clamp(1.75rem, 2.6vw, 2.5rem);
    margin-bottom: 0.75rem;
}

.section-head p {
    color: var(--muted);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 40;
    background: rgba(248, 250, 252, 0.9);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(226, 232, 240, 0.8);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.02em;
}

.logo-icon {
    width: 2.5rem;
    height: 2.5rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 0.85rem;
    background: linear-gradient(140deg, var(--primary), var(--accent));
    color: white;
    font-weight: 800;
}

.nav {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    font-weight: 600;
}

.nav a {
    color: var(--muted);
    transition: color 0.2s ease;
}

.nav a:hover {
    color: var(--text);
}

.nav a.active {
    color: var(--primary);
    position: relative;
}

.nav a.active::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: -0.4rem;
    height: 2px;
    background: var(--accent);
    border-radius: 999px;
}

.nav-toggle {
    display: none;
    align-items: center;
    justify-content: center;
    width: 2.7rem;
    height: 2.7rem;
    flex-direction: column;
    gap: 0.28rem;
    border: 1px solid var(--border);
    border-radius: 0.8rem;
    background: #ffffff;
    cursor: pointer;
    box-shadow: 0 6px 16px rgba(15, 23, 42, 0.08);
    transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.nav-toggle span {
    width: 1.15rem;
    height: 2px;
    border-radius: 999px;
    background: var(--text);
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle.open span:first-child {
    transform: translateY(6px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.open span:last-child {
    transform: translateY(-6px) rotate(-45deg);
}

.nav-toggle:hover {
    border-color: rgba(30, 58, 138, 0.35);
    box-shadow: 0 10px 20px rgba(15, 23, 42, 0.12);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.85rem 1.75rem;
    border-radius: 999px;
    font-weight: 600;
    border: 1px solid transparent;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 10px 20px rgba(30, 58, 138, 0.2);
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-outline {
    border-color: var(--border);
    color: var(--text);
    background: white;
}

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

.btn-ghost {
    border-color: transparent;
    color: var(--primary);
}

.nav-cta {
    background: var(--primary);
    color: white;
    padding: 0.55rem 1.25rem;
    box-shadow: 0 10px 20px rgba(30, 58, 138, 0.2);
}

.nav-cta:hover {
    background: var(--primary-dark);
}

.hero {
    position: relative;
    padding: 6rem 0 5rem;
    overflow: hidden;
    background:
        linear-gradient(120deg, rgba(248, 250, 252, 0.95), rgba(248, 250, 252, 0.7)),
        url('../img/hero.png') center/cover no-repeat,
        radial-gradient(circle at top, rgba(20, 184, 166, 0.08), transparent 60%);
}

.hero-glow {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 80% 20%, rgba(30, 58, 138, 0.16), transparent 50%);
    pointer-events: none;
}

.hero-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 3rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content h1 {
    font-family: 'Noto Serif', serif;
    font-size: clamp(1.9rem, 2.6vw, 2.5rem);
    line-height: 1.1;
    margin-bottom: 1rem;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    padding: 0.35rem 0.9rem;
    border-radius: 999px;
    background: rgba(20, 184, 166, 0.12);
    color: var(--accent-dark);
    font-weight: 700;
    font-size: 0.8rem;
    margin-bottom: 1rem;
}

.lead {
    font-size: 1.1rem;
    color: var(--muted);
    margin-bottom: 2rem;
}

.hero-meta {
    display: grid;
    gap: 1rem;
    margin-bottom: 2rem;
}

.meta-item {
    background: white;
    padding: 0.9rem 1.1rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
}

.meta-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--muted);
}

.meta-value {
    display: block;
    font-weight: 600;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 1.75rem;
}

.trust-line {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--muted);
    font-size: 0.9rem;
}

.trust-logos {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.trust-logos img {
    height: 62px;
    filter: grayscale(20%);
}

.hero-card {
    background: white;
    border-radius: 1.5rem;
    padding: 2rem;
    box-shadow: var(--shadow);
    border: 1px solid rgba(226, 232, 240, 0.8);
}

.hero-card-header p {
    color: var(--muted);
    font-size: 0.9rem;
}

.hero-card-header h3 {
    font-size: 1.5rem;
    margin-top: 0.25rem;
}

.hero-points {
    list-style: none;
    margin: 1.5rem 0;
    display: grid;
    gap: 0.75rem;
}

.hero-points li {
    padding-left: 1.5rem;
    position: relative;
}

.hero-points li::before {
    content: '';
    width: 0.6rem;
    height: 0.6rem;
    background: var(--accent);
    border-radius: 50%;
    position: absolute;
    left: 0;
    top: 0.5rem;
}

.hero-card-footer {
    display: grid;
    gap: 1rem;
}

.small {
    color: var(--muted);
    font-size: 0.8rem;
}

.strong {
    font-weight: 600;
}

.split {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 3rem;
    align-items: center;
}

.about {
    background: white;
}

.about h2 {
    font-family: 'Noto Serif', serif;
    font-size: clamp(1.8rem, 2.4vw, 2.4rem);
    margin-bottom: 1rem;
}

.about p {
    color: var(--muted);
    margin-bottom: 1.5rem;
}

.chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.chips span {
    padding: 0.5rem 0.9rem;
    border-radius: 999px;
    background: rgba(30, 58, 138, 0.08);
    color: var(--primary);
    font-weight: 600;
    font-size: 0.85rem;
}

.feature-grid {
    display: grid;
    gap: 1rem;
}

.feature-card {
    background: var(--bg);
    padding: 1.5rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
}

.feature-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.audience-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
}

.audience-item {
    padding: 1.25rem;
    border-radius: 1rem;
    background: white;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    font-weight: 600;
    text-align: center;
    align-items: center;
    display: flex;
    justify-content: center;
}

.program {
    background: linear-gradient(180deg, #ffffff, #f1f5f9);
}

.timeline {
    display: grid;
    gap: 1rem;
    max-width: 860px;
    margin: 0 auto;
}

.timeline-item {
    display: grid;
    grid-template-columns: 130px 1fr;
    gap: 1.5rem;
    padding: 1.25rem 1.5rem;
    background: white;
    border-radius: 1rem;
    border: 1px solid var(--border);
    position: relative;
    box-shadow: var(--shadow);
    transition:
        transform 0.28s ease,
        box-shadow 0.28s ease,
        border-color 0.28s ease,
        background-color 0.28s ease;
    overflow: hidden;
}

.timeline-item::after {
    content: '';
    position: absolute;
    inset: 0 auto 0 0;
    width: 4px;
    background: linear-gradient(180deg, var(--accent), var(--accent-dark));
    opacity: 0;
    transition: opacity 0.28s ease;
}

.timeline-item.break {
    background: rgba(20, 184, 166, 0.08);
}

.timeline-item:hover {
    transform: translateY(-4px);
    border-color: rgba(20, 184, 166, 0.35);
    box-shadow: 0 16px 28px rgba(15, 23, 42, 0.14);
    background: #ffffff;
}

.timeline-item:hover::after {
    opacity: 1;
}

.timeline-item:hover .time {
    color: var(--accent-dark);
}

.timeline-item .content h3 {
    margin: 0;
    font-size: 1.1rem;
    line-height: 1.6;
    font-weight: normal;
    color: var(--text);
}

.timeline-item .time {
    font-size: 1rem;
    font-weight: 700;
    color: var(--primary);
    white-space: nowrap;
}

.tag {
    display: inline-block;
    padding: 0.2rem 0.6rem;
    border-radius: 999px;
    background: rgba(20, 184, 166, 0.12);
    color: var(--accent-dark);
    font-size: 0.75rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.speaker {
    position: relative;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    overflow: hidden;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.speaker .split {
    align-items: center;
    gap: 2.5rem;
    padding: clamp(1.25rem, 2vw, 2rem);
    border-radius: 1.5rem;
    border: 1px solid var(--border);
    background: #ffffff;
    box-shadow: 0 14px 32px rgba(15, 23, 42, 0.06);
}

.speaker-photo {
    height: clamp(360px, 42vw, 520px);
    width: 100%;
    max-width: 460px;
    margin: 0 auto;
    border-radius: 1.25rem;
    border: 1px solid rgba(30, 58, 138, 0.12);
    background-image:
        url('../img/kasatkin_bg_without.png'),
        radial-gradient(120% 90% at 50% 80%, rgba(20, 184, 166, 0.16) 0%, rgba(20, 184, 166, 0) 65%),
        linear-gradient(180deg, #f8fbff 0%, #eef3f8 100%);
    background-size: contain, 100% 100%, 100% 100%;
    background-repeat: no-repeat, no-repeat, no-repeat;
    background-position: center bottom, center, center;
    box-shadow: inset 0 -14px 20px rgba(15, 23, 42, 0.06);
    position: relative;
    overflow: hidden;
}

.speaker-photo::before {
    content: none;
}

.speaker-photo::after {
    content: none;
}

.speaker-info h2 {
    font-family: 'Noto Serif', serif;
    font-size: clamp(1.4rem, 2.4vw, 1.6rem);
    margin-bottom: 0.5rem;
}

.speaker-info {
    max-width: 640px;
}

.speaker-role {
    color: var(--accent-dark);
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.speaker-bullets {
    display: grid;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    color: var(--muted);
}

.speaker-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.speaker-stats .stat {
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary);
    display: block;
}

.stat-label {
    font-size: 0.85rem;
    color: var(--muted);
}

.organizers {
    background: var(--bg);
}

.organizers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.5rem;
}

.organizer-card {
    background: white;
    padding: 2rem;
    border-radius: 1.25rem;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
}

.organizer-card.highlight {
    border: 1px solid rgba(20, 184, 166, 0.3);
    background: linear-gradient(140deg, rgba(20, 184, 166, 0.08), white);
}

.organizer-logo {
    height: 66px;
    margin-bottom: 1.25rem;
}

.organizer-card h3 {
    margin-bottom: 0.75rem;
}

.organizer-card p {
    color: var(--muted);
    margin-bottom: 1rem;
}

.organizer-card ul {
    list-style: none;
    display: grid;
    gap: 0.5rem;
}

.organizer-card ul li {
    position: relative;
    padding-left: 1.2rem;
}

.organizer-card ul li::before {
    content: '';
    width: 0.5rem;
    height: 0.5rem;
    background: var(--accent);
    border-radius: 50%;
    position: absolute;
    left: 0;
    top: 0.5rem;
}

.cta {
    background: radial-gradient(circle at top left, rgba(30, 58, 138, 0.3), transparent 60%),
        linear-gradient(140deg, var(--primary), var(--accent-dark));
    color: white;
    padding: 4rem 0;
}

.cta-inner {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    align-items: center;
    gap: 2rem;
}

.cta h2 {
    font-family: 'Noto Serif', serif;
    font-size: clamp(1.8rem, 2.4vw, 2.4rem);
    margin-bottom: 0.75rem;
}

.cta p {
    color: rgba(255, 255, 255, 0.8);
}

.mobile-cta {
    display: none;
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 1rem;
    background: rgba(248, 250, 252, 0.96);
    border-top: 1px solid var(--border);
    z-index: 35;
}

.back-to-top {
    position: fixed;
    right: 1.5rem;
    bottom: 1.5rem;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background: var(--primary);
    color: white;
    font-size: 1.1rem;
    font-weight: 700;
    box-shadow: var(--shadow);
    cursor: pointer;
    opacity: 0;
    transform: translateY(10px);
    pointer-events: none;
    transition: all 0.2s ease;
    z-index: 36;
}

.back-to-top.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(6px);
    align-items: center;
    justify-content: center;
    z-index: 50;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: white;
    border-radius: 1.5rem;
    width: min(620px, 92vw);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.modal-header {
    background: linear-gradient(120deg, var(--primary), var(--accent));
    color: white;
    padding: 1.5rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-subtitle {
    color: rgba(255, 255, 255, 0.75);
    font-size: 0.9rem;
}

.modal-close {
    background: none;
    border: none;
    color: white;
    font-size: 1.8rem;
    cursor: pointer;
}

.modal-body {
    padding: 2rem;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.form-group {
    display: grid;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.form-group label {
    font-weight: 600;
    font-size: 0.9rem;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.7rem 1rem;
    border-radius: 0.8rem;
    border: 1px solid var(--border);
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus {
    outline: 2px solid rgba(30, 58, 138, 0.3);
    border-color: var(--primary);
}

.consent {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.9rem;
    color: var(--muted);
    margin-top: 1rem;
}

.consent a {
    color: var(--primary);
    text-decoration: underline;
    text-underline-offset: 2px;
}

.form-buttons {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.form-error {
    margin-top: 0.85rem;
    color: #b91c1c;
    font-size: 0.88rem;
    font-weight: 600;
}

.form-buttons .btn:disabled {
    opacity: 0.65;
    cursor: not-allowed;
    pointer-events: none;
}

.success {
    text-align: center;
    padding: 2rem 0;
}

.success-icon {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background: rgba(20, 184, 166, 0.2);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.site-footer {
    position: relative;
    padding: 3.5rem 0 2rem;
    background:
        radial-gradient(circle at 12% 0%, rgba(20, 184, 166, 0.08), transparent 36%),
        radial-gradient(circle at 90% 100%, rgba(30, 58, 138, 0.08), transparent 42%),
        linear-gradient(180deg, #f8fbff 0%, #eef4fb 100%);
    color: var(--text);
    border-top: 1px solid var(--border);
}

.footer-shell {
    border: 1px solid rgba(148, 163, 184, 0.22);
    border-radius: 1.5rem;
    padding: clamp(1.2rem, 2vw, 2rem);
    background: rgba(255, 255, 255, 0.86);
    box-shadow: 0 16px 36px rgba(15, 23, 42, 0.08);
}

.footer-brand {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.footer-logo .logo-text {
    color: var(--text);
    font-size: 1.15rem;
}

.footer-brand p {
    max-width: 620px;
    color: var(--muted);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 0.9rem;
    margin-bottom: 1.4rem;
}

.footer-card {
    border: 1px solid rgba(148, 163, 184, 0.28);
    border-radius: 1rem;
    padding: 1rem;
    background: #ffffff;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.05);
}

.footer-grid h4 {
    color: var(--primary);
    margin-bottom: 0.45rem;
    font-size: 0.95rem;
}

.footer-card p {
    color: var(--muted);
    line-height: 1.55;
    font-size: 0.95rem;
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    border-top: 1px solid rgba(148, 163, 184, 0.35);
    padding-top: 1rem;
    font-size: 0.9rem;
    color: var(--muted);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.9rem;
}

.footer-links a {
    color: var(--primary);
    padding: 0.15rem 0;
    border-bottom: 1px solid transparent;
    transition: color 0.2s ease, border-color 0.2s ease;
}

.footer-links a:hover {
    color: var(--accent-dark);
    border-color: rgba(15, 118, 110, 0.35);
}

@media (max-width: 900px) {
    .site-header {
        background: rgba(255, 255, 255, 0.95);
        border-bottom: 1px solid rgba(226, 232, 240, 0.95);
    }

    .header-inner {
        min-height: 4.2rem;
        padding: 0.7rem 0;
    }

    .logo-text {
        font-size: 1.35rem;
    }

    .nav {
        position: fixed;
        left: 0.75rem;
        right: 0.75rem;
        top: calc(4.2rem + 0.55rem);
        background: white;
        border-radius: 1rem;
        border: 1px solid var(--border);
        box-shadow: 0 20px 40px rgba(15, 23, 42, 0.16);
        padding: 0.9rem;
        display: grid;
        gap: 0.3rem;
        max-height: calc(100vh - 6rem);
        overflow-y: auto;
        transform: translateY(-14px) scale(0.98);
        opacity: 0;
        visibility: hidden;
        pointer-events: none;
        transition: transform 0.2s ease, opacity 0.2s ease, visibility 0.2s ease;
        z-index: 55;
    }

    .nav.open {
        transform: translateY(0) scale(1);
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
    }

    .nav a {
        padding: 0.75rem 0.7rem;
        border-radius: 0.7rem;
    }

    .nav a:hover,
    .nav a.active {
        background: #f1f5f9;
    }

    .nav-toggle {
        display: flex;
        margin-right: 0.2rem;
    }

    .nav-cta {
        width: 100%;
        justify-content: center;
    }

    .mobile-cta {
        display: block;
    }

    .hero {
        padding-top: 4rem;
    }

    .timeline-item {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 600px) {
    body {
        padding-bottom: 5rem;
    }

    .site-header {
        backdrop-filter: blur(10px);
    }

    .hero {
        padding: 3.5rem 0 4rem;
    }

    .hero-content h1 {
        font-size: clamp(1.7rem, 5.8vw, 2.4rem);
    }

    .lead {
        font-size: 1rem;
    }

    .hero-meta {
        gap: 0.75rem;
    }

    .meta-item {
        padding: 0.75rem 1rem;
    }

    .trust-line {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }

    .hero-card {
        padding: 1.5rem;
    }

    .section {
        padding: 4rem 0;
    }

    .section-head {
        text-align: left;
    }

    .audience-grid {
        grid-template-columns: 1fr;
    }

    .timeline-item {
        padding: 1rem;
        gap: 0.75rem;
    }

    .timeline-item .time {
        font-size: 0.9rem;
    }

    .speaker-photo {
        height: 340px;
        background-position: center bottom;
        max-width: 380px;
    }

    .speaker .split {
        padding: 1rem;
        gap: 1.5rem;
    }

    .speaker-stats {
        grid-template-columns: 1fr 1fr;
    }

    .cta-inner {
        text-align: left;
    }

    .hero-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .form-buttons {
        flex-direction: column;
    }

    .footer-grid {
        grid-template-columns: 1fr;
    }

    .footer-brand {
        flex-direction: column;
        align-items: flex-start;
    }

    .footer-bottom {
        flex-direction: column;
        align-items: flex-start;
    }
}