/* =========================================
   PRESENTATION — Акцент v2.1 (СВЕТЛАЯ ВЕРСИЯ)
   Зависит от ../css/tokens.css
   ========================================= */

/* --- BASE RESET (портируем из main.css) --- */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-family: var(--font-sans);
    font-size: var(--text-body-base);
    color: var(--color-text-main);
    background: var(--gray-50);
    /* ← СВЕТЛЫЙ ФОН ВСЁЙ СТРАНИЦЫ */
    scroll-behavior: smooth;
}

body {
    min-height: 100vh;
    overflow-x: hidden;
}

h1,
h2,
h3 {
    color: var(--color-text-heading);
    font-weight: 700;
    margin-bottom: var(--space-4);
    letter-spacing: -0.02em;
}

p {
    margin-bottom: var(--space-4);
    line-height: 1.6;
}

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

/* --- HEADER (порт из main.css) --- */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--gray-900);
    /* шапка остаётся тёмной — контраст */
    border-bottom: 2px solid var(--color-primary-base);
    height: 64px;
    display: flex;
    align-items: center;
}

.header .wide-container {
    width: 100%;
    padding: 0 var(--container-padding);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    height: 40px;
    display: flex;
    align-items: center;
}

.logo img {
    height: 100%;
    width: auto;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--space-6);
}

.header-contacts {
    display: flex;
    align-items: center;
    gap: var(--space-6);
}

.header-contacts a {
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--gray-400);
    transition: color 0.2s;
}

.header-contacts a:hover {
    color: var(--white);
}

/* Кнопка «Вернуться» */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 24px;
    border-radius: var(--radius-sm);
    font-weight: 700;
    font-family: var(--font-sans);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-size: 12px;
    cursor: pointer;
    border: none;
    transition: all 0.2s ease-in-out;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--gray-600);
    color: var(--gray-400);
}

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

.btn-primary {
    background: var(--color-primary-base);
    color: var(--color-text-inverse);
}

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

/* --- SIDEBAR NAVIGATION --- */
.pres-sidebar {
    position: fixed;
    left: 0;
    top: 64px;
    width: 260px;
    height: calc(100vh - 64px);
    background: transparent;
    /* ← ПРОЗРАЧНЫЙ ФОН */
    border-right: 1px solid rgba(196, 30, 58, 0.12);
    z-index: 900;
    overflow-y: auto;
    padding: var(--space-4) 0;
    scrollbar-width: thin;
    scrollbar-color: var(--gray-400) transparent;
}

.pres-sidebar::-webkit-scrollbar {
    width: 4px;
}

.pres-sidebar::-webkit-scrollbar-track {
    background: transparent;
}

.pres-sidebar::-webkit-scrollbar-thumb {
    background: var(--gray-400);
    border-radius: 2px;
}

.pres-nav {
    list-style: none;
}

.pres-nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 20px;
    cursor: pointer;
    transition: all 0.25s ease;
    border-left: 3px solid transparent;
    text-decoration: none;
    background: rgba(255, 255, 255, 0.85);
    /* лёгкая подложка для читаемости */
}

.pres-nav-item:hover,
.pres-nav-item.active {
    background: rgba(255, 255, 255, 0.95);
    border-left-color: var(--color-primary-base);
}

.nav-num {
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 600;
    color: var(--color-primary-base);
    border: 1px solid var(--color-primary-base);
    border-radius: 2px;
    width: 28px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all 0.25s ease;
}

.pres-nav-item.active .nav-num {
    background: var(--color-primary-base);
    color: var(--white);
}

.nav-label {
    font-size: 12px;
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    transition: color 0.25s ease;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.pres-nav-item.active .nav-label {
    color: var(--gray-900);
    font-weight: 600;
}

.pres-nav-item:hover .nav-label {
    color: var(--gray-800);
}

/* --- MAIN SCROLL CONTAINER --- */
.pres-main {
    margin-left: 260px;
    margin-top: 64px;
    height: calc(100vh - 64px);
    overflow-y: scroll;
    scroll-snap-type: y mandatory;
    background: var(--gray-50);
}

/* --- SECTION (полноэкранная) --- */
.pres-section {
    height: calc(100vh - 64px);
    scroll-snap-align: start;
    display: grid;
    grid-template-columns: 70% 30%;
    gap: 0;
    align-items: stretch;
    position: relative;
    border-bottom: 1px solid rgba(196, 30, 58, 0.08);
    /* Светлая граница */
}

/* Левая колонка — контент */
.pres-content {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: var(--space-8) var(--space-10) var(--space-8) var(--space-8);
    background: var(--white);
    /* ← СВЕТЛЫЙ ФОН КОНТЕНТА */
    position: relative;
    overflow: hidden;
}

/* Номер секции в углу */
.pres-slide-num {
    position: absolute;
    top: var(--space-6);
    left: var(--space-8);
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-primary-base);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    display: flex;
    align-items: center;
    gap: 12px;
}

.pres-slide-num::before {
    content: '';
    display: block;
    width: 32px;
    height: 2px;
    background: var(--color-primary-base);
}

/* Section Tag — порт из main.css */
.section-tag {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--color-primary-base);
    text-transform: uppercase;
    letter-spacing: 0.15em;
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.section-tag::before {
    content: '';
    display: block;
    width: 32px;
    height: 2px;
    background: var(--color-primary-base);
}

.pres-content h2 {
    font-size: var(--text-h2);
    line-height: 1.15;
    color: var(--gray-900);
    margin-bottom: var(--space-4);
    max-width: 640px;
}

.pres-content h2 em {
    color: var(--brand-red-500);
    font-style: normal;
}

.pres-content p {
    font-size: var(--text-body-lg);
    color: var(--gray-800);
    line-height: 1.7;
    max-width: 580px;
}

.pres-content .lead {
    font-size: 20px;
    color: var(--gray-900);
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: var(--space-6);
}

/* Списки в контенте */
.pres-list {
    list-style: none;
    margin: var(--space-4) 0;
}

.pres-list li {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 16px;
    font-size: 15px;
    color: var(--gray-800);
    line-height: 1.5;
}

.pres-list li::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--color-primary-base);
    border-radius: 1px;
    flex-shrink: 0;
    margin-top: 7px;
}

/* Цифры/статистика внутри секций */
.pres-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: var(--space-6);
    margin: var(--space-6) 0;
}

.pres-stat-val {
    font-family: var(--font-mono);
    font-size: 48px;
    font-weight: 700;
    color: var(--gray-900);
    line-height: 1;
}

.pres-stat-val span {
    color: var(--color-primary-base);
}

.pres-stat-label {
    font-size: 12px;
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-top: 8px;
}

/* Карточки внутри секций */
.pres-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: var(--space-4) 0;
}

.pres-card {
    border: 1px solid var(--gray-200);
    padding: var(--space-4);
    border-radius: var(--radius-sm);
    transition: border-color 0.3s;
}

.pres-card:hover {
    border-color: var(--color-primary-base);
}

.pres-card h4 {
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--gray-900);
}

.pres-card p {
    font-size: 13px;
    color: var(--gray-600);
    margin-bottom: 0;
    line-height: 1.5;
}

/* Шаги процесса */
.pres-steps {
    display: flex;
    gap: 24px;
    margin: var(--space-4) 0;
    counter-reset: step;
}

.pres-step {
    flex: 1;
    counter-increment: step;
    padding-top: 40px;
    position: relative;
}

.pres-step::before {
    content: counter(step, decimal-leading-zero);
    position: absolute;
    top: 0;
    left: 0;
    font-family: var(--font-mono);
    font-size: 24px;
    font-weight: 700;
    color: var(--color-primary-base);
}

.pres-step h4 {
    font-size: 14px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 6px;
}

.pres-step p {
    font-size: 13px;
    color: var(--gray-600);
    margin-bottom: 0;
    line-height: 1.5;
}

/* Тёмные секции (инверсия ОТКЛЮЧЕНА, заменяем на чуть другой светлый фон) */
.pres-section--dark .pres-content {
    background: var(--gray-50);
}

.pres-section--dark .pres-content h2,
.pres-section--dark .pres-content .lead {
    color: var(--gray-900);
}

.pres-section--dark .pres-content p,
.pres-section--dark .pres-content .pres-stat-label,
.pres-section--dark .pres-list li,
.pres-section--dark .pres-card p,
.pres-section--dark .pres-step p {
    color: var(--gray-800);
}

.pres-section--dark .pres-content h2 em,
.pres-section--dark .pres-slide-num,
.pres-section--dark .pres-step::before {
    color: var(--brand-red-500);
}

.pres-section--dark .pres-stat-val,
.pres-section--dark .pres-card h4,
.pres-section--dark .pres-step h4 {
    color: var(--gray-900);
}

.pres-section--dark .pres-card {
    border-color: var(--gray-200);
    background: var(--white);
}

.pres-section--dark .pres-card:hover {
    border-color: var(--color-primary-base);
}

/* --- ПРАВАЯ КОЛОНКА — ВИЗУАЛ (СВЕТЛЫЙ placeholder) --- */
.pres-visual {
    background: linear-gradient(160deg, #f8f9fa 0%, #e9ecef 100%);
    position: relative;
    overflow: hidden;
}

/* Тёмный (теперь красный) слабый overlay поверх визуала */
.pres-visual::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(196, 30, 58, 0.03) 0%, rgba(196, 30, 58, 0.08) 100%);
    z-index: 1;
}

/* Диагональные «трассировки» — CSS-only декор */
.pres-visual::after {
    content: '';
    position: absolute;
    inset: 0;
    background:
        linear-gradient(45deg,
            transparent 48%,
            rgba(196, 30, 58, 0.04) 49%,
            rgba(196, 30, 58, 0.04) 51%,
            transparent 52%),
        linear-gradient(-30deg,
            transparent 46%,
            rgba(134, 142, 150, 0.04) 47%,
            rgba(134, 142, 150, 0.04) 53%,
            transparent 54%);
    background-size: 80px 80px, 120px 120px;
    z-index: 2;
}

/* Номер секции внутри визуала (крупный) */
.pres-visual-num {
    position: absolute;
    bottom: var(--space-6);
    right: var(--space-6);
    font-family: var(--font-mono);
    font-size: 72px;
    font-weight: 700;
    color: rgba(196, 30, 58, 0.1);
    line-height: 1;
    z-index: 3;
}

/* Вариации визуалов — чтобы не все были одинаковые (СВЕТЛЫЕ) */
.pres-visual--alt1 {
    background:
        repeating-linear-gradient(90deg, transparent, transparent 59px, rgba(134, 142, 150, 0.05) 59px, rgba(134, 142, 150, 0.05) 60px),
        repeating-linear-gradient(0deg, transparent, transparent 59px, rgba(134, 142, 150, 0.05) 59px, rgba(134, 142, 150, 0.05) 60px),
        linear-gradient(135deg, #ffffff 0%, #e9ecef 50%, #f8f9fa 100%);
    background-size: 60px 60px, 60px 60px, 100% 100%;
}

.pres-visual--alt2 {
    background:
        repeating-linear-gradient(45deg, transparent, transparent 19px, rgba(196, 30, 58, 0.03) 19px, rgba(196, 30, 58, 0.03) 20px),
        linear-gradient(180deg, #f1f3f5 0%, #e9ecef 100%);
    background-size: 20px 20px, 100% 100%;
}

.pres-visual--alt3 {
    background:
        radial-gradient(circle at 70% 30%, rgba(196, 30, 58, 0.05) 0%, transparent 50%),
        repeating-linear-gradient(0deg, transparent, transparent 29px, rgba(206, 212, 218, 0.2) 29px, rgba(206, 212, 218, 0.2) 30px),
        repeating-linear-gradient(90deg, transparent, transparent 29px, rgba(206, 212, 218, 0.2) 29px, rgba(206, 212, 218, 0.2) 30px),
        linear-gradient(200deg, #f8f9fa 0%, #e9ecef 100%);
    background-size: 100% 100%, 30px 30px, 30px 30px, 100% 100%;
}

/* --- FADE-IN ANIMATIONS --- */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.25, 1, 0.5, 1), transform 0.8s cubic-bezier(0.25, 1, 0.5, 1);
}

.fade-in.active {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger children */
.pres-content>*:nth-child(1) {
    transition-delay: 0.05s;
}

.pres-content>*:nth-child(2) {
    transition-delay: 0.15s;
}

.pres-content>*:nth-child(3) {
    transition-delay: 0.25s;
}

.pres-content>*:nth-child(4) {
    transition-delay: 0.35s;
}

.pres-content>*:nth-child(5) {
    transition-delay: 0.45s;
}

/* --- RESPONSIVE --- */
@media (max-width: 1200px) {
    .pres-sidebar {
        width: 200px;
    }

    .pres-main {
        margin-left: 200px;
    }

    .nav-label {
        font-size: 11px;
    }
}

@media (max-width: 1024px) {
    .pres-sidebar {
        display: none;
    }

    .pres-main {
        margin-left: 0;
    }

    .pres-section {
        grid-template-columns: 1fr;
    }

    .pres-visual {
        position: absolute;
        inset: 0;
        opacity: 0.12;
        z-index: 0;
    }

    .pres-content {
        position: relative;
        z-index: 1;
        background: rgba(255, 255, 255, 0.97);
    }

    .pres-section--dark .pres-content {
        background: rgba(248, 249, 250, 0.97);
    }
}

@media (max-width: 768px) {
    .header-contacts {
        display: none;
    }

    .pres-content {
        padding: var(--space-6) var(--space-4);
    }

    .pres-content h2 {
        font-size: clamp(22px, 5vw, 32px);
    }

    .pres-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-4);
    }

    .pres-stat-val {
        font-size: 36px;
    }

    .pres-cards {
        grid-template-columns: 1fr;
    }

    .pres-steps {
        flex-direction: column;
        gap: 16px;
    }
}

@media (max-width: 480px) {
    .pres-content h2 {
        font-size: 22px;
    }

    .pres-content p {
        font-size: 15px;
    }

    .pres-slide-num {
        font-size: 10px;
        top: var(--space-4);
        left: var(--space-4);
    }
}

/* --- MASCOTS --- */
.pres-mascot-wrapper {
    position: absolute;
    bottom: 0;
    left: 70%;
    height: 33vh;
    z-index: 10;
    pointer-events: none;
}

.pres-mascot-wrapper .pres-mascot {
    height: 100%;
    width: auto;
    display: block;
    transform: translateX(-35%);
}

@media (max-width: 1024px) {
    .pres-mascot-wrapper {
        left: auto;
        right: var(--space-4);
        height: 25vh;
        opacity: 0.6;
    }
    .pres-mascot-wrapper .pres-mascot {
        transform: translateX(0);
    }
}

@media (max-width: 768px) {
    .pres-mascot-wrapper {
        display: none;
    }
}