/* ============================================
   ALVEON Brand Strategy — Design System
   ============================================ */

:root {
    /* Colors */
    --color-black: #0A0A0A;
    --color-dark: #111111;
    --color-dark-2: #1A1A1A;
    --color-dark-3: #222222;
    --color-gray: #6B6B6B;
    --color-gray-light: #9A9A9A;
    --color-gray-lighter: #B0B0B0;
    --color-border: #222222;
    --color-border-light: #333333;
    --color-white: #EAEAEA;
    --color-white-bright: #FAFAFA;
    --color-accent: #C8FF00;
    --color-accent-dim: rgba(200, 255, 0, 0.08);
    --color-accent-mid: rgba(200, 255, 0, 0.15);
    --color-red-dim: rgba(255, 80, 80, 0.08);
    --color-red: #FF5050;
    --color-green-dim: rgba(80, 255, 120, 0.08);
    --color-green: #50FF78;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.8125rem;
    --font-size-base: 0.9375rem;
    --font-size-md: 1.0625rem;
    --font-size-lg: 1.25rem;
    --font-size-xl: 1.5rem;
    --font-size-2xl: 2rem;
    --font-size-3xl: 2.5rem;

    /* Spacing */
    --space-xs: 0.375rem;
    --space-sm: 0.75rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    --space-4xl: 6rem;

    /* Layout */
    --sidebar-width: 280px;
    --content-max: 720px;
    --content-padding: 3rem;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
}

/* ============================================
   Reset & Base
   ============================================ */

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 2rem;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: 400;
    line-height: 1.7;
    color: var(--color-gray-lighter);
    background-color: var(--color-black);
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-white-bright);
}

::selection {
    background-color: var(--color-accent);
    color: var(--color-black);
}

/* ============================================
   Mobile Header
   ============================================ */

.mobile-header {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 200;
    height: 56px;
    background-color: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    padding: 0 var(--space-lg);
    align-items: center;
    justify-content: space-between;
}

.mobile-header__logo {
    font-size: var(--font-size-lg);
    font-weight: 800;
    letter-spacing: 0.08em;
    color: var(--color-white-bright);
}

.mobile-header__toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px 4px;
}

.mobile-header__toggle span {
    display: block;
    width: 20px;
    height: 1.5px;
    background-color: var(--color-white);
    transition: transform var(--transition-base), opacity var(--transition-base);
}

.mobile-header__toggle--open span:nth-child(1) {
    transform: rotate(45deg) translate(4px, 4px);
}

.mobile-header__toggle--open span:nth-child(2) {
    opacity: 0;
}

.mobile-header__toggle--open span:nth-child(3) {
    transform: rotate(-45deg) translate(4px, -4px);
}

/* ============================================
   Sidebar
   ============================================ */

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background-color: var(--color-dark);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    z-index: 150;
    overflow-y: auto;
}

.sidebar__header {
    padding: var(--space-xl) var(--space-lg);
    border-bottom: 1px solid var(--color-border);
    flex-shrink: 0;
}

.sidebar__logo {
    display: block;
    font-size: var(--font-size-xl);
    font-weight: 800;
    letter-spacing: 0.08em;
    color: var(--color-white-bright);
}

.sidebar__subtitle {
    display: block;
    font-size: var(--font-size-xs);
    font-weight: 500;
    color: var(--color-gray);
    letter-spacing: 0.05em;
    margin-top: var(--space-xs);
}

.sidebar__nav {
    flex: 1;
    padding: var(--space-md) 0;
    overflow-y: auto;
}

.sidebar__link {
    display: block;
    padding: var(--space-sm) var(--space-lg);
    font-size: var(--font-size-sm);
    font-weight: 400;
    color: var(--color-gray) !important;
    text-decoration: none;
    transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
    border-left: 2px solid transparent;
    line-height: 1.4;
    white-space: nowrap;
}

.sidebar__link:hover {
    color: var(--color-white) !important;
    background-color: var(--color-accent-dim);
}

.sidebar__link--active {
    color: var(--color-white-bright) !important;
    border-left-color: var(--color-accent);
    background-color: var(--color-accent-dim);
}

.sidebar__num {
    display: inline-block;
    width: 24px;
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--color-gray);
    font-variant-numeric: tabular-nums;
}

.sidebar__link--active .sidebar__num {
    color: var(--color-accent);
}

.sidebar__footer {
    padding: var(--space-lg);
    border-top: 1px solid var(--color-border);
    flex-shrink: 0;
}

.sidebar__badge {
    display: inline-block;
    font-size: 0.625rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-accent);
    border: 1px solid var(--color-accent);
    padding: 2px 8px;
}

.sidebar__version {
    display: block;
    font-size: var(--font-size-xs);
    color: var(--color-gray);
    margin-top: var(--space-sm);
}

.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.6);
    z-index: 140;
}

/* ============================================
   Main Content
   ============================================ */

.content {
    margin-left: var(--sidebar-width);
    padding: var(--space-4xl) var(--content-padding) var(--space-3xl);
    max-width: calc(var(--content-max) + var(--content-padding) * 2 + var(--sidebar-width));
}

/* ============================================
   Chapter
   ============================================ */

.chapter {
    padding-bottom: var(--space-4xl);
    margin-bottom: var(--space-4xl);
    border-bottom: 1px solid var(--color-border);
    scroll-margin-top: 2rem;
}

.chapter:last-child {
    border-bottom: none;
    margin-bottom: var(--space-2xl);
}

.chapter__header {
    margin-bottom: var(--space-2xl);
}

.chapter__number {
    display: block;
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.15em;
    color: var(--color-accent);
    margin-bottom: var(--space-sm);
    font-variant-numeric: tabular-nums;
}

.chapter__title {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    color: var(--color-white-bright);
}

.chapter__lead {
    font-size: var(--font-size-md);
    color: var(--color-white);
    line-height: 1.8;
    margin-bottom: var(--space-lg);
}

/* ============================================
   Typography within chapters
   ============================================ */

.chapter h2 {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-white-bright);
    letter-spacing: -0.01em;
    margin-top: var(--space-3xl);
    margin-bottom: var(--space-lg);
}

.chapter h2:first-of-type {
    margin-top: 0;
}

.chapter h3 {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-white);
    margin-top: var(--space-2xl);
    margin-bottom: var(--space-md);
}

.chapter p {
    margin-bottom: var(--space-md);
    max-width: var(--content-max);
}

.chapter p:last-child {
    margin-bottom: 0;
}

/* ============================================
   Quote Block
   ============================================ */

.quote-block {
    border-left: 3px solid var(--color-accent);
    padding: var(--space-lg) var(--space-xl);
    margin: var(--space-xl) 0;
    background-color: var(--color-accent-dim);
    font-size: var(--font-size-md);
    font-style: italic;
    color: var(--color-white);
    line-height: 1.8;
    max-width: var(--content-max);
}

/* ============================================
   Callout
   ============================================ */

.callout {
    padding: var(--space-lg) var(--space-xl);
    margin: var(--space-lg) 0;
    background-color: var(--color-dark-2);
    border: 1px solid var(--color-border-light);
    max-width: var(--content-max);
}

.callout p {
    font-size: var(--font-size-base);
    color: var(--color-gray-lighter);
    line-height: 1.7;
    margin-bottom: 0;
}

/* ============================================
   Definition List
   ============================================ */

.def-list {
    margin: var(--space-xl) 0;
    max-width: var(--content-max);
}

.def-list__item {
    padding: var(--space-lg) 0;
    border-bottom: 1px solid var(--color-border);
}

.def-list__item:first-child {
    padding-top: 0;
}

.def-list__item:last-child {
    border-bottom: none;
}

.def-list__item dt {
    font-size: var(--font-size-base);
    font-weight: 700;
    color: var(--color-white-bright);
    margin-bottom: var(--space-xs);
}

.def-list__item dd {
    font-size: var(--font-size-base);
    color: var(--color-gray-lighter);
    line-height: 1.7;
}

.def-list__item--alert {
    padding: var(--space-lg);
    margin-top: var(--space-md);
    background-color: var(--color-red-dim);
    border: 1px solid rgba(255, 80, 80, 0.2);
    border-bottom: 1px solid rgba(255, 80, 80, 0.2);
}

.def-list__item--alert dt {
    color: var(--color-red);
}

/* ============================================
   Do / Don't Comparison
   ============================================ */

.do-dont {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1px;
    margin: var(--space-lg) 0;
    max-width: var(--content-max);
    background-color: var(--color-border);
}

.do-dont__col {
    padding: var(--space-lg);
}

.do-dont__col--do {
    background-color: var(--color-green-dim);
}

.do-dont__col--dont {
    background-color: var(--color-red-dim);
}

.do-dont__label {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    margin-bottom: var(--space-md);
}

.do-dont__col--do .do-dont__label {
    color: var(--color-green);
}

.do-dont__col--dont .do-dont__label {
    color: var(--color-red);
}

.do-dont__col p {
    font-size: var(--font-size-sm);
    color: var(--color-gray-lighter);
    line-height: 1.7;
    font-style: italic;
    margin-bottom: 0;
}

/* ============================================
   Tag (inline label)
   ============================================ */

.tag {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: 600;
    letter-spacing: 0.08em;
    color: var(--color-gray);
    background-color: var(--color-dark-3);
    padding: 2px 10px;
    margin-left: var(--space-sm);
    vertical-align: middle;
    font-style: normal;
    text-transform: uppercase;
}

/* ============================================
   Audience Card
   ============================================ */

.audience-card {
    padding: var(--space-xl);
    margin: var(--space-xl) 0;
    border: 1px solid var(--color-border-light);
    background-color: var(--color-dark-2);
    max-width: var(--content-max);
}

.audience-card__title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-white-bright);
    margin-bottom: var(--space-sm);
}

.audience-card__desc {
    color: var(--color-gray-lighter);
    margin-bottom: var(--space-lg);
}

.audience-card__sub {
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-top: var(--space-lg);
    margin-bottom: var(--space-sm);
}

.audience-card p {
    margin-bottom: 0;
}

/* ============================================
   Fact Table
   ============================================ */

.fact-table {
    width: 100%;
    max-width: var(--content-max);
    border-collapse: collapse;
    margin: var(--space-lg) 0;
}

.fact-table thead th {
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-gray);
    text-align: left;
    padding: var(--space-sm) var(--space-md);
    border-bottom: 2px solid var(--color-border-light);
}

.fact-table tbody td {
    font-size: var(--font-size-sm);
    color: var(--color-gray-lighter);
    padding: var(--space-sm) var(--space-md);
    border-bottom: 1px solid var(--color-border);
    vertical-align: top;
    line-height: 1.6;
}

.fact-table tbody td:first-child {
    width: 200px;
    color: var(--color-white);
    white-space: nowrap;
}

.fact-table tbody tr:last-child td {
    border-bottom: none;
}

.fact-table tbody td strong {
    color: var(--color-white);
    font-weight: 600;
}

/* LinkedIn icon link */
.linkedin-link {
    display: inline-flex;
    align-items: center;
    vertical-align: middle;
    margin-left: 4px;
    color: var(--color-gray) !important;
    transition: color var(--transition-fast);
}

.linkedin-link:hover {
    color: var(--color-white-bright) !important;
}

.linkedin-icon {
    width: 14px;
    height: 14px;
}

/* ============================================
   Roadmap Phase
   ============================================ */

.roadmap-phase {
    display: grid;
    grid-template-columns: 120px 1fr;
    gap: var(--space-xl);
    margin: var(--space-xl) 0;
    max-width: var(--content-max);
}

.roadmap-phase__marker {
    text-align: right;
    padding-top: var(--space-xs);
}

.roadmap-phase__year {
    display: block;
    font-size: var(--font-size-2xl);
    font-weight: 800;
    color: var(--color-white-bright);
    letter-spacing: -0.02em;
    line-height: 1;
}

.roadmap-phase__tag {
    display: inline-block;
    margin-top: var(--space-sm);
    font-size: 0.625rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--color-accent);
    border: 1px solid var(--color-accent);
    padding: 2px 8px;
}

.roadmap-phase__tag--highlight {
    background-color: var(--color-accent);
    color: var(--color-black);
}

.roadmap-phase__body {
    border-left: 1px solid var(--color-border-light);
    padding-left: var(--space-xl);
    padding-bottom: var(--space-xl);
}

.roadmap-phase__body h3 {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-white);
    margin-top: 0;
    margin-bottom: var(--space-md);
}

.roadmap-phase__body > p {
    margin-bottom: var(--space-lg);
}

.roadmap-phase__meta {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
    padding: var(--space-lg);
    background-color: var(--color-dark-2);
    border: 1px solid var(--color-border);
}

.roadmap-phase__meta strong {
    display: block;
    font-size: var(--font-size-xs);
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-xs);
}

.roadmap-phase__meta p {
    font-size: var(--font-size-sm);
    color: var(--color-gray-lighter);
    line-height: 1.6;
    margin-bottom: 0;
}

/* ============================================
   Footer
   ============================================ */

.footer {
    margin-left: var(--sidebar-width);
    border-top: 1px solid var(--color-border);
    padding: var(--space-lg) var(--content-padding);
}

.footer__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--content-max);
}

.footer__logo {
    font-size: var(--font-size-sm);
    font-weight: 800;
    letter-spacing: 0.08em;
    color: var(--color-gray);
}

.footer__meta {
    font-size: var(--font-size-xs);
    color: var(--color-gray);
}

/* ============================================
   Reveal Animations
   ============================================ */

.reveal {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.reveal--visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Responsive — Tablet & smaller (< 1024px)
   ============================================ */

@media (max-width: 1023px) {
    :root {
        --sidebar-width: 260px;
        --content-padding: 2rem;
    }
}

/* ============================================
   Responsive — Mobile (< 768px)
   ============================================ */

@media (max-width: 767px) {
    .mobile-header {
        display: flex;
    }

    .sidebar {
        transform: translateX(-100%);
        transition: transform var(--transition-base);
        width: 280px;
    }

    .sidebar--open {
        transform: translateX(0);
    }

    .sidebar-overlay--visible {
        display: block;
    }

    .content {
        margin-left: 0;
        padding: calc(56px + var(--space-2xl)) var(--space-lg) var(--space-2xl);
        max-width: none;
    }

    .footer {
        margin-left: 0;
        padding: var(--space-lg);
    }

    .footer__inner {
        flex-direction: column;
        gap: var(--space-sm);
        text-align: center;
    }

    .chapter__title {
        font-size: var(--font-size-2xl);
    }

    .do-dont {
        grid-template-columns: 1fr;
    }

    .roadmap-phase {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }

    .roadmap-phase__marker {
        text-align: left;
        display: flex;
        align-items: center;
        gap: var(--space-md);
    }

    .roadmap-phase__body {
        border-left: none;
        padding-left: 0;
    }

    .roadmap-phase__meta {
        grid-template-columns: 1fr;
    }

    .fact-table tbody td:first-child {
        white-space: normal;
        width: auto;
        min-width: 120px;
    }

    .chapter {
        padding-bottom: var(--space-3xl);
        margin-bottom: var(--space-3xl);
    }
}