* { box-sizing: border-box; }

html {
    scroll-behavior: smooth;
    scroll-snap-type: y proximity;
}

html, body {
    margin: 0;
    min-height: 100%;
}

body {
    background: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-body);
    font-weight: var(--body-weight);
    letter-spacing: var(--body-tracking);
    line-height: 1.55;
}

a {
    color: inherit;
    text-decoration-thickness: 1px;
    text-underline-offset: 0.2em;
}

/* —— Shell —— */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 40;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    flex-wrap: wrap;
    padding: 12px 16px;
    background: color-mix(in oklab, var(--bg-color) 82%, transparent);
    border-bottom: 1px solid transparent;
    backdrop-filter: blur(12px);
    transition: border-color 0.25s ease, background 0.25s ease;
}

.header-tools {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-left: auto;
}

.lang-switch {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: color-mix(in oklab, var(--card-bg) 70%, transparent);
}

.lang-switch a {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    text-decoration: none;
    padding: 6px 10px;
    border-radius: 999px;
    opacity: 0.65;
    white-space: nowrap;
}

.lang-switch a[aria-current="page"] {
    opacity: 1;
    background: color-mix(in oklab, var(--overlay-color) 22%, transparent);
    color: var(--text-color);
}

.series-chip {
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--muted);
    white-space: nowrap;
}

.site-header.is-scrolled {
    border-bottom-color: var(--line);
    background: color-mix(in oklab, var(--bg-color) 92%, black);
}

.brand-lockup {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.brand-lockup img,
.brand-lockup svg {
    width: 36px;
    height: auto;
    overflow: visible;
}

.brand-name {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.78rem;
}

.progress {
    position: absolute;
    left: 0;
    bottom: 0;
    height: 2px;
    width: 0%;
    background: linear-gradient(90deg, var(--logo-color), var(--overlay-color));
    transition: width 0.08s linear;
}

.nav-dots {
    display: none;
    gap: 8px;
    align-items: center;
}

.nav-dots a {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: color-mix(in oklab, var(--text-color) 28%, transparent);
    text-indent: -9999px;
    overflow: hidden;
    transition: background 0.2s ease, transform 0.2s ease;
}

.nav-dots a[aria-current="true"] {
    background: var(--overlay-color);
    transform: scale(1.25);
}

/* —— Slides —— */
.deck {
    padding-top: 64px;
}

.slide {
    min-height: calc(100vh - 64px);
    scroll-snap-align: start;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px 72px;
}

.slide-inner {
    width: 100%;
    max-width: 720px;
    display: flex;
    flex-direction: column;
    gap: 22px;
}

.slide-tall {
    min-height: auto;
    padding-top: 48px;
    padding-bottom: 88px;
    align-items: flex-start;
}

.kicker {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0;
}

.display {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    margin: 0;
    line-height: 1.08;
}

.h1 { font-size: clamp(2rem, 6.5vw, 2.85rem); }
.h2 { font-size: clamp(1.45rem, 4vw, 1.9rem); }

.lede,
.body {
    margin: 0;
    font-size: 1.05rem;
    line-height: 1.7;
    max-width: 40ch;
}

.lede { opacity: 0.92; }
.body { opacity: 0.88; color: color-mix(in oklab, var(--text-color) 92%, transparent); }

.muted { color: var(--muted); }

.panel {
    background: var(--card-bg);
    border: 1px solid var(--line);
    border-radius: 20px;
    padding: 28px 24px;
}

.panel-tight { padding: 20px; }

/* —— Cover —— */
.cover {
    text-align: center;
    align-items: center;
}

.cover .logo-hero {
    width: min(148px, 42vw);
    height: auto;
    margin: 0 auto 8px;
    overflow: visible;
}

.cover .lede {
    margin: 0 auto;
    text-align: center;
}

.scroll-hint {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    margin-top: 12px;
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--muted);
    text-decoration: none;
}

.scroll-hint .chevron {
    width: 10px;
    height: 10px;
    border-right: 1.5px solid var(--overlay-color);
    border-bottom: 1.5px solid var(--overlay-color);
    transform: rotate(45deg);
    animation: bob 1.6s ease-in-out infinite;
}

@keyframes bob {
    0%, 100% { transform: translateY(0) rotate(45deg); opacity: 0.55; }
    50% { transform: translateY(5px) rotate(45deg); opacity: 1; }
}

/* —— Timeline —— */
.timeline {
    display: grid;
    gap: 12px;
}

@media (min-width: 720px) {
    .timeline {
        grid-template-columns: repeat(3, 1fr);
        gap: 14px;
    }
}

.timeline-act {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 18px 16px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: color-mix(in oklab, var(--card-bg) 70%, black);
    min-height: 100%;
}

.timeline-act .era {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--overlay-color);
    margin: 0;
}

.timeline-act .act-title {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.82rem;
    margin: 0;
}

.timeline-act .act-sub {
    margin: 0;
    font-size: 0.88rem;
    opacity: 0.85;
    line-height: 1.45;
}

.milestone-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.milestone {
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    padding: 6px 10px;
    border-radius: 999px;
    border: 1px solid var(--line);
    color: var(--muted);
}

.analogy {
    margin: 0;
    padding: 14px 16px;
    border-left: 2px solid var(--logo-color);
    font-size: 0.95rem;
    line-height: 1.6;
    opacity: 0.92;
}

.analogy strong {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--logo-color);
    font-weight: 500;
    margin-bottom: 6px;
}

.takeaway {
    margin: 0;
    padding: 18px 20px;
    border: 1px solid color-mix(in oklab, var(--overlay-color) 40%, transparent);
    border-radius: 20px;
    background: color-mix(in oklab, var(--overlay-color) 8%, var(--card-bg));
    font-size: 1.05rem;
    line-height: 1.55;
}

/* —— Type cards —— */
.type-grid {
    display: grid;
    gap: 12px;
}

@media (min-width: 720px) {
    .type-grid.two { grid-template-columns: 1fr 1fr; }
}

.type-card {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 18px 16px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
}

.type-card .type-code {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--overlay-color);
    margin: 0;
}

.type-card h3 {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.88rem;
    margin: 0;
}

.type-card p {
    margin: 0;
    font-size: 0.92rem;
    opacity: 0.88;
    line-height: 1.55;
}

.type-card .type-note {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0;
}

/* —— Day-to-day —— */
.use-grid {
    display: grid;
    gap: 12px;
}

@media (min-width: 720px) {
    .use-grid { grid-template-columns: 1fr 1fr; }
}

.use-block {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: color-mix(in oklab, var(--card-bg) 70%, black);
}

.use-block h3 {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.78rem;
    margin: 0;
}

.use-block ul {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.use-block li {
    position: relative;
    padding-left: 1.1em;
    font-size: 0.9rem;
    opacity: 0.88;
    line-height: 1.4;
}

.use-block li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.55em;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--overlay-color);
}

/* —— Tools —— */
.tool-grid {
    display: grid;
    gap: 12px;
}

@media (min-width: 720px) {
    .tool-grid { grid-template-columns: 1fr 1fr; }
}

.tool-card {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 18px 16px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
    text-decoration: none;
    transition: border-color 0.2s ease, background 0.2s ease;
}

.tool-card:hover {
    border-color: color-mix(in oklab, var(--overlay-color) 50%, transparent);
    background: color-mix(in oklab, var(--overlay-color) 6%, var(--card-bg));
}

.tool-card .tool-name {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.82rem;
    margin: 0;
}

.tool-card .tool-vendor {
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0;
}

.tool-card .tool-analogy {
    margin: 0;
    font-size: 0.9rem;
    opacity: 0.88;
    line-height: 1.5;
}

.tool-card .tool-link {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--overlay-color);
    margin-top: auto;
}

/* —— Labs —— */
.lab {
    display: flex;
    flex-direction: column;
    gap: 14px;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
}

.lab-note {
    margin: 0;
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.04em;
    color: var(--muted);
}

.seg {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.seg-btn,
.btn {
    appearance: none;
    border: 1px solid rgba(128, 128, 128, 0.35);
    background: transparent;
    color: var(--text-color);
    border-radius: 12px;
    padding: 10px 12px;
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: clamp(0.58rem, 1.6vw, 0.68rem);
    letter-spacing: 0.03em;
    text-transform: uppercase;
    opacity: 0.75;
    transition: opacity 0.2s ease, border-color 0.2s ease, background 0.2s ease;
    white-space: normal;
    text-align: center;
    line-height: 1.25;
    max-width: 100%;
}

.seg-btn.is-active,
.btn:hover:not(:disabled) {
    opacity: 1;
    border-color: var(--text-color);
    background: rgba(128, 128, 128, 0.12);
}

.seg-btn.is-active {
    border-color: var(--overlay-color);
}

.btn {
    opacity: 1;
    border-color: color-mix(in oklab, var(--logo-color) 55%, transparent);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-ghost {
    border-color: rgba(128, 128, 128, 0.35);
}

.tool-rec {
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding: 16px;
    border: 1px solid color-mix(in oklab, var(--overlay-color) 40%, transparent);
    border-radius: 20px;
    background: color-mix(in oklab, var(--bg-color) 55%, black);
}

.tool-rec .rec-tool {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 1.05rem;
    margin: 0;
}

.tool-rec .rec-body {
    margin: 0;
    font-size: 0.95rem;
    line-height: 1.55;
    opacity: 0.9;
}

.sample-label {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0 0 8px;
}

/* —— Resources —— */
.resource-groups {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.resource-group h3 {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--overlay-color);
    margin: 0 0 10px;
}

.resource-list {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.resource-list a {
    display: flex;
    flex-direction: column;
    gap: 4px;
    padding: 12px 14px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
    text-decoration: none;
    transition: border-color 0.2s ease;
}

.resource-list a:hover {
    border-color: color-mix(in oklab, var(--overlay-color) 45%, transparent);
}

.resource-list .res-title {
    font-size: 0.95rem;
    opacity: 0.95;
}

.resource-list .res-meta {
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--muted);
}

/* —— Steps / recap —— */
.steps {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin: 0;
    padding: 0;
    list-style: none;
}

.steps li {
    display: grid;
    grid-template-columns: 36px 1fr;
    gap: 12px;
    align-items: start;
}

.steps .n {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.06em;
    color: var(--overlay-color);
    padding-top: 4px;
}

.steps strong {
    display: block;
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.82rem;
    margin-bottom: 4px;
}

.steps span {
    font-size: 0.95rem;
    opacity: 0.88;
}

.recap {
    margin: 0;
    padding-left: 1.2rem;
    text-align: left;
    max-width: 36ch;
    display: flex;
    flex-direction: column;
    gap: 8px;
    font-size: 0.98rem;
    opacity: 0.9;
}

.closing {
    text-align: center;
    align-items: center;
}

.closing .lede,
.closing .body {
    margin-inline: auto;
    text-align: center;
}

.footer-meta {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    letter-spacing: var(--mono-tracking);
    text-transform: uppercase;
    color: var(--muted);
    margin: 0;
}

.footer-meta a,
.connect-trigger {
    appearance: none;
    color: var(--overlay-color);
    text-decoration: none;
    background: transparent;
    border: none;
    border-bottom: 1px solid color-mix(in oklab, var(--overlay-color) 45%, transparent);
    border-radius: 0;
    padding: 0;
    margin: 0;
    font: inherit;
    letter-spacing: inherit;
    text-transform: inherit;
    opacity: 1;
    cursor: pointer;
}

.footer-meta a:hover,
.connect-trigger:hover,
.connect-trigger[aria-expanded="true"] {
    color: var(--text-color);
    border-bottom-color: color-mix(in oklab, var(--text-color) 45%, transparent);
}

.series-next {
    display: flex;
    flex-direction: column;
    gap: 6px;
    width: 100%;
    max-width: 36ch;
    margin-inline: auto;
    padding: 18px 20px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
    text-decoration: none;
    text-align: left;
    transition: border-color 0.2s ease;
}

a.series-next:hover {
    border-color: color-mix(in oklab, var(--overlay-color) 50%, transparent);
}

.series-next.is-soon {
    opacity: 0.78;
    border-style: dashed;
}

.series-next-kicker {
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--muted);
}

.series-next-title {
    font-family: var(--font-display);
    font-weight: var(--display-weight);
    letter-spacing: var(--display-tracking);
    text-transform: var(--display-transform);
    font-size: 0.88rem;
}

.series-next-url {
    font-family: var(--font-mono);
    font-size: 0.62rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--overlay-color);
}

.connect {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    width: 100%;
    max-width: 420px;
    margin-inline: auto;
}

.connect-panel {
    width: 100%;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: var(--card-bg);
    text-align: left;
}

.connect-panel[hidden] {
    display: none;
}

.connect-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
}

@media (min-width: 520px) {
    .connect-grid { grid-template-columns: repeat(3, 1fr); }
}

.connect-grid a {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 84px;
    padding: 12px 8px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: color-mix(in oklab, var(--bg-color) 55%, black);
    text-decoration: none;
    font-family: var(--font-mono);
    font-size: 0.58rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--muted);
    transition: border-color 0.2s ease, color 0.2s ease;
}

.connect-grid a:hover {
    border-color: color-mix(in oklab, var(--overlay-color) 50%, transparent);
    color: var(--text-color);
}

.connect-grid svg {
    width: 22px;
    height: 22px;
    color: var(--overlay-color);
}

/* —— Motion —— */
.reveal {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.is-in {
    opacity: 1;
    transform: none;
}

.timeline > .timeline-act {
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.45s ease, transform 0.45s ease;
}

.timeline.is-in > .timeline-act {
    opacity: 1;
    transform: none;
}

.timeline.is-in > .timeline-act:nth-child(1) { transition-delay: 0.05s; }
.timeline.is-in > .timeline-act:nth-child(2) { transition-delay: 0.15s; }
.timeline.is-in > .timeline-act:nth-child(3) { transition-delay: 0.25s; }

/* —— Consent —— */
.consent {
    position: fixed;
    left: 12px;
    right: 12px;
    bottom: 12px;
    z-index: 50;
    display: none;
    gap: 14px;
    align-items: flex-start;
    justify-content: space-between;
    flex-wrap: wrap;
    padding: 16px 18px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: color-mix(in oklab, var(--card-bg) 92%, black);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.35);
}

.consent.is-visible { display: flex; }

.consent p {
    margin: 0;
    flex: 1 1 220px;
    font-size: 0.88rem;
    line-height: 1.5;
    opacity: 0.9;
}

.consent-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

@media (min-width: 900px) {
    .nav-dots { display: flex; }
    .site-header { padding: 16px 28px; }
    .slide { padding: 48px 28px 80px; }
    .series-chip { display: inline; }
}

@media (max-width: 899px) {
    .series-chip { display: none; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .reveal,
    .timeline > .timeline-act,
    .scroll-hint .chevron {
        animation: none !important;
        transition: none !important;
        opacity: 1 !important;
        transform: none !important;
    }
}