:root {
  --bg: #0c1017;
  --bg-elev: #141b26;
  --ink: #e8eef6;
  --muted: #8b9bb0;
  --line: rgba(232, 238, 246, 0.12);
  --accent: #e08a3c;
  --accent-soft: rgba(224, 138, 60, 0.16);
  --good: #3d9a6a;
  --bad: #c45a5a;
  --font: "Outfit", system-ui, sans-serif;
  --serif: "Literata", Georgia, serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --rail: 5.5rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1.05rem;
  line-height: 1.5;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

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

h1,
h2,
h3 {
  margin: 0 0 0.85rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
}

h1 {
  font-size: clamp(2.2rem, 5.5vw, 4rem);
  max-width: 14ch;
}

h2 {
  font-size: clamp(1.7rem, 3.4vw, 2.75rem);
  max-width: 22ch;
}

h3 {
  font-size: 1.15rem;
}

p {
  margin: 0 0 1rem;
}

.kicker {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1rem;
}

.lede {
  font-family: var(--serif);
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: rgba(232, 238, 246, 0.82);
  max-width: 36rem;
  margin-bottom: 1.75rem;
}

.sub {
  color: var(--muted);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}

.note {
  color: var(--muted);
  font-size: 0.98rem;
  max-width: 44rem;
  margin-top: 1.5rem;
}

/* Rail */
.rail {
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: var(--rail);
  z-index: 20;
  display: none;
  flex-direction: column;
  align-items: center;
  padding: 1.25rem 0.5rem;
  border-right: 1px solid var(--line);
  background: rgba(12, 16, 23, 0.92);
  backdrop-filter: blur(10px);
}

.rail-brand {
  font-weight: 800;
  letter-spacing: 0.08em;
  font-size: 0.85rem;
  margin-bottom: 1.5rem;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
}

.rail-nav {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  flex: 1;
  justify-content: center;
}

.rail-dot {
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 50%;
  border: 0;
  padding: 0;
  background: rgba(232, 238, 246, 0.25);
  cursor: pointer;
  transition: transform 0.2s var(--ease), background 0.2s var(--ease);
}

.rail-dot.is-active {
  background: var(--accent);
  transform: scale(1.35);
}

.rail-hint {
  font-size: 0.65rem;
  color: var(--muted);
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

@media (min-width: 900px) {
  .rail {
    display: flex;
  }

  .deck {
    margin-left: var(--rail);
  }
}

/* Slides */
.deck {
  scroll-snap-type: y mandatory;
  height: 100svh;
  overflow-y: auto;
}

.slide {
  min-height: 100svh;
  scroll-snap-align: start;
  scroll-snap-stop: always;
  display: grid;
  align-items: center;
  padding: 3.5rem 1.25rem 4rem;
  position: relative;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(900px 420px at 100% 0%, rgba(224, 138, 60, 0.08), transparent 55%),
    var(--bg);
}

.slide-inner {
  max-width: 980px;
  margin: 0 auto;
  width: 100%;
  animation: rise 0.55s var(--ease) both;
}

.slide-hero {
  padding: 0;
  background: #000;
}

.hero-bg {
  position: absolute;
  inset: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.55;
  transform: scale(1.06);
  animation: drift 16s var(--ease) infinite alternate;
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(8, 12, 18, 0.92) 0%, rgba(8, 12, 18, 0.55) 55%, rgba(8, 12, 18, 0.35) 100%),
    linear-gradient(180deg, rgba(8, 12, 18, 0.2) 0%, rgba(8, 12, 18, 0.85) 100%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding: 5rem 1.25rem 4rem;
  max-width: 980px;
  margin: 0 auto;
}

@keyframes drift {
  from {
    transform: scale(1.06) translate(0, 0);
  }
  to {
    transform: scale(1.12) translate(-1%, -1%);
  }
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-cta,
.end-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.9rem;
  padding: 0.7rem 1.2rem;
  font: inherit;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.2s var(--ease), background 0.2s var(--ease), border-color 0.2s var(--ease);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-accent {
  background: var(--accent);
  color: #1a1008;
}

.btn-line {
  border-color: rgba(232, 238, 246, 0.35);
  background: transparent;
  color: var(--ink);
}

.btn-line:hover {
  border-color: #fff;
}

.split {
  display: grid;
  gap: 1.75rem;
  margin-top: 1.5rem;
}

.split.tight {
  margin-top: 1.75rem;
}

@media (min-width: 800px) {
  .split {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 2.5rem;
    align-items: start;
  }
}

.ticks {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.65rem;
}

.ticks li {
  position: relative;
  padding-left: 1.15rem;
  color: rgba(232, 238, 246, 0.88);
}

.ticks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.45rem;
  height: 0.45rem;
  background: var(--accent);
}

.ticks.bad li::before {
  background: var(--bad);
}

.ticks.good li::before {
  background: var(--good);
}

.layers {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-top: 1.5rem;
}

.layers article {
  background: var(--bg-elev);
  padding: 1.35rem 1.25rem;
}

.layers span {
  display: block;
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--accent);
  margin-bottom: 0.5rem;
  font-weight: 700;
}

.layers p {
  color: var(--muted);
  margin: 0;
  font-size: 0.95rem;
}

@media (min-width: 800px) {
  .layers {
    grid-template-columns: repeat(4, 1fr);
  }
}

.method-grid {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.75rem;
  counter-reset: none;
}

.method-grid li {
  padding: 1rem 1.1rem;
  background: var(--bg-elev);
  border-left: 3px solid var(--accent);
  font-size: 1.05rem;
}

.method-grid strong {
  color: var(--accent);
  margin-right: 0.65rem;
  font-variant-numeric: tabular-nums;
}

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

.callout {
  background: var(--accent-soft);
  border: 1px solid rgba(224, 138, 60, 0.35);
  padding: 1.35rem 1.25rem;
}

.callout-label {
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.callout p:last-child {
  margin: 0;
  color: rgba(232, 238, 246, 0.9);
}

.two-cols {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

@media (min-width: 800px) {
  .two-cols {
    grid-template-columns: 1fr 1fr;
  }
}

.panel {
  background: var(--bg-elev);
  border: 1px solid var(--line);
  padding: 1.4rem 1.25rem;
}

.panel h3 {
  margin-bottom: 0.75rem;
}

.panel p {
  color: rgba(232, 238, 246, 0.82);
}

.meta {
  margin: 1rem 0 0 !important;
  font-size: 0.85rem !important;
  color: var(--accent) !important;
  font-weight: 600;
}

.flow {
  display: grid;
  gap: 0.5rem;
  margin: 1.5rem 0 0.5rem;
}

@media (min-width: 800px) {
  .flow {
    grid-template-columns: repeat(5, 1fr);
  }
}

.flow-step {
  background: var(--bg-elev);
  border: 1px solid var(--line);
  padding: 1rem 0.85rem;
  font-size: 0.92rem;
  font-weight: 600;
  display: grid;
  gap: 0.45rem;
}

.flow-step span {
  width: 1.5rem;
  height: 1.5rem;
  display: grid;
  place-items: center;
  background: var(--accent);
  color: #1a1008;
  font-size: 0.8rem;
}

.seg-table {
  margin-top: 1.5rem;
  border: 1px solid var(--line);
}

.seg-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.35rem;
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--line);
  background: var(--bg-elev);
}

.seg-row:last-child {
  border-bottom: 0;
}

.seg-row.head {
  background: transparent;
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 600;
}

@media (min-width: 800px) {
  .seg-row {
    grid-template-columns: 1.2fr 1.1fr 0.7fr 1.2fr;
    gap: 1rem;
    align-items: center;
  }

  .risks .seg-row {
    grid-template-columns: 1fr 1.1fr 1.4fr;
  }
}

.phases {
  display: grid;
  gap: 1rem;
  margin-top: 1.5rem;
}

@media (min-width: 800px) {
  .phases {
    grid-template-columns: repeat(3, 1fr);
  }
}

.phases article {
  background: var(--bg-elev);
  border-top: 3px solid var(--accent);
  padding: 1.35rem 1.2rem;
}

.phase-num {
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.phases ul {
  margin: 0.85rem 0 0;
  padding: 0 0 0 1.1rem;
  color: var(--muted);
  display: grid;
  gap: 0.4rem;
  font-size: 0.95rem;
}

.plain {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.plain th,
.plain td {
  text-align: left;
  padding: 0.75rem 0.5rem;
  border-bottom: 1px solid var(--line);
}

.plain th {
  color: var(--muted);
  font-weight: 600;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.kpi-stack {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.kpi {
  background: var(--bg-elev);
  border: 1px solid var(--line);
  padding: 1.1rem;
  display: grid;
  gap: 0.25rem;
}

.kpi strong {
  font-size: 1.45rem;
  letter-spacing: -0.03em;
  color: var(--accent);
}

.kpi span {
  color: var(--muted);
  font-size: 0.85rem;
}

.next-steps {
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1rem;
  counter-reset: step;
}

.next-steps li {
  counter-increment: step;
  position: relative;
  padding: 1.2rem 1.2rem 1.2rem 3.5rem;
  background: var(--bg-elev);
  border: 1px solid var(--line);
}

.next-steps li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 1rem;
  top: 1.2rem;
  font-weight: 800;
  color: var(--accent);
  font-size: 0.95rem;
}

.next-steps strong {
  display: block;
  margin-bottom: 0.25rem;
}

.progress {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  height: 3px;
  z-index: 30;
  background: rgba(255, 255, 255, 0.06);
}

.progress-bar {
  height: 100%;
  width: 0;
  background: var(--accent);
  transition: width 0.25s var(--ease);
}

@media (min-width: 900px) {
  .progress {
    left: var(--rail);
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .hero-bg img,
  .slide-inner {
    animation: none !important;
  }

  .deck {
    scroll-snap-type: none;
  }
}

@media print {
  .rail,
  .progress,
  .hero-cta,
  .end-cta {
    display: none !important;
  }

  .deck {
    margin: 0;
    height: auto;
    overflow: visible;
    scroll-snap-type: none;
  }

  .slide {
    min-height: auto;
    page-break-after: always;
    border: 0;
    padding: 2rem;
    background: #fff;
    color: #111;
  }

  .kicker,
  .accent,
  .meta,
  .phase-num,
  .kpi strong,
  .layers span {
    color: #b45a10 !important;
  }

  .panel,
  .layers article,
  .seg-row,
  .phases article,
  .flow-step,
  .kpi,
  .next-steps li {
    background: #f4f4f4;
    color: #111;
    border-color: #ddd;
  }

  .hero-bg {
    display: none;
  }

  .slide-hero {
    background: #111;
    color: #fff;
    padding: 2rem;
  }
}