:root {
  --black: #000;
  --ink: #111;
  --text: #1a1a1a;
  --muted: #555;
  --muted-2: #666;
  --line: #d8d8d8;
  --line-soft: #e3e3e3;
  --line-strong: #111;
  --bg-alt: #f5f5f5;
  --ph-bg: #e9e9e9;
  --ph-line: #c9c9c9;
  --font-sans: "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;
}

html {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  padding: 40px 24px;
  background: #e8e8e8;
  color: var(--text);
  font: 400 18px/1.55 var(--font-sans);
}

h1, h2, h3, h4, p, figure, dl, dd, dt, ul, ol {
  margin: 0;
}

ul, ol {
  padding: 0;
}

a {
  color: inherit;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:visited {
  color: inherit;
}

button {
  font: inherit;
}

.sheet {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  background: #fff;
  outline: 1px solid #c9c9c9;
}

/* Prototype legend */

.spec {
  background: #f2f2f2;
  border-bottom: 2px solid var(--line-strong);
}

.spec__bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding: 10px 24px;
  background: var(--ink);
  color: #fff;
  font: 400 10px/1.4 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.spec__title {
  font-weight: 700;
}

.spec__meta {
  color: #bdbdbd;
}

.spec__body {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  padding: 24px;
}

.spec__col {
  grid-column: span 4;
  min-width: 0;
}

.spec__col + .spec__col {
  border-left: 1px solid #d0d0d0;
  padding-left: 24px;
}

.spec__label {
  margin-bottom: 16px;
  color: var(--ink);
  font: 600 10px/1.4 var(--font-mono);
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.spec__hint {
  margin-top: 12px;
  color: #555;
  font: 400 11px/1.5 var(--font-mono);
}

.scale {
  display: flex;
  flex-direction: column;
}

.scale__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 2px 0;
  border-bottom: 1px solid #dcdcdc;
}

.scale__row:last-child {
  border-bottom: 0;
}

.scale__sample {
  color: var(--black);
  font-weight: 600;
  line-height: 0.95;
  letter-spacing: -0.03em;
}

.scale__sample--h1 { font-size: 64px; }
.scale__sample--h2 { font-size: 40px; }
.scale__sample--h3 { font-size: 24px; }
.scale__sample--h4 { font-size: 20px; }
.scale__sample--lead { font-size: 20px; font-weight: 400; }
.scale__sample--body { font-size: 18px; font-weight: 400; }
.scale__sample--small { font-size: 15px; font-weight: 400; }

.scale__sample--mono {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: 0;
}

.scale__meta {
  color: #555;
  font: 400 9px/1.3 var(--font-mono);
  letter-spacing: 0.03em;
  white-space: nowrap;
}

.spec-list > div {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 6px 0;
  border-bottom: 1px solid #dcdcdc;
}

.spec-list dt {
  color: #555;
  font: 400 10px/1.4 var(--font-mono);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.spec-list dd {
  color: var(--black);
  font: 600 11px/1.4 var(--font-mono);
  text-align: right;
  white-space: nowrap;
}

.mini-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 4px;
  height: 30px;
  margin-top: 16px;
}

.mini-grid span {
  background: #cfcfcf;
}

.ph-legend {
  display: flex;
  flex-direction: column;
  gap: 7px;
  list-style: none;
}

.ph-legend li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-bottom: 7px;
  border-bottom: 1px solid #dcdcdc;
}

.ph-legend li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.ph-legend__icon {
  display: flex;
  flex: none;
  align-items: center;
  justify-content: center;
  width: 44px;
}

.ph-legend__shape {
  display: block;
  border: 1px solid #bdbdbd;
  background: #dedede;
}

.ph-legend__shape--photo { width: 24px; height: 30px; }
.ph-legend__shape--shot { width: 40px; height: 25px; }
.ph-legend__shape--vector { width: 32px; height: 26px; }
.ph-legend__shape--icon { width: 26px; height: 26px; }

.ph-legend__name {
  color: var(--ink);
  font: 600 10px/1.3 var(--font-mono);
  letter-spacing: 0.04em;
}

.ph-legend__meta {
  margin-left: auto;
  color: #555;
  font: 400 9px/1.3 var(--font-mono);
  white-space: nowrap;
}

.spec__foot {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 16px;
  padding: 10px 24px;
  border-top: 1px solid #d0d0d0;
  background: #ececec;
  color: #555;
  font: 400 10px/1.4 var(--font-mono);
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.spec__foot-label {
  color: var(--ink);
  font-weight: 600;
}

.spec__foot-sample {
  color: #333;
}

/* Page and visible grid */

.page {
  position: relative;
  background: #fff;
}

.guides {
  position: absolute;
  top: 0;
  right: 24px;
  bottom: 0;
  left: 24px;
  z-index: 1;
  pointer-events: none;
}

.guides__cols {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  height: 100%;
}

.guides__cols span {
  border-right: 1px solid #e0e0e0;
  border-left: 1px solid #e0e0e0;
}

.block {
  border-top: 1px solid var(--line);
  background: #fff;
}

.block--hero {
  border-top: 0;
}

.block--alt {
  background: var(--bg-alt);
}

.block__inner {
  position: relative;
  z-index: 2;
  padding: 96px 24px;
}

.block__label {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 10px;
  padding-bottom: 12px;
  margin-bottom: 48px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font: 400 11px/1.4 var(--font-mono);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.block__number {
  color: var(--ink);
  font-weight: 700;
}

.block__number::after {
  content: " /";
  color: #999;
}

.block__code {
  color: var(--ink);
  font-weight: 700;
  letter-spacing: 0.08em;
}

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

.block__spec {
  margin-left: auto;
  color: var(--muted-2);
  font-size: 10px;
  white-space: nowrap;
}

/* Type */

.h1 {
  color: var(--black);
  font-size: 64px;
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -0.03em;
}

.h2 {
  color: var(--black);
  font-size: 40px;
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.h3 {
  color: var(--black);
  font-size: 24px;
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.lead {
  font-size: 20px;
  line-height: 1.45;
}

.small {
  font-size: 15px;
  line-height: 1.5;
}

.micro {
  color: var(--muted-2);
  font: 400 10px/1.4 var(--font-mono);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.micro--invert {
  color: #b5b5b5;
}

/* Shared layout */

.section-head {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  align-items: start;
  margin-bottom: 48px;
}

.section-head > .h2 {
  grid-column: span 12;
}

.section-head--icon > .h2 {
  grid-column: span 9;
}

.section-head--icon > .ph {
  grid-column: span 3;
}

.btn {
  appearance: none;
  -webkit-appearance: none;
  display: inline-block;
  padding: 17px 26px;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: var(--ink);
  color: #fff;
  font: 600 17px/1.2 var(--font-sans);
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

.btn:focus-visible {
  outline: 2px solid currentColor;
  outline-offset: 3px;
}

.btn--invert {
  border-color: #fff;
  background: #fff;
  color: var(--ink);
}

.btn:visited {
  color: #fff;
}

.btn--invert:visited {
  color: var(--ink);
}

.sticky-cta {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 90;
  border-bottom: 1px solid var(--ink);
  background: #fff;
}

.sticky-cta[hidden] {
  display: none;
}

.sticky-cta__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 24px;
}

.sticky-cta__title {
  color: var(--ink);
  font-size: 18px;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.sticky-cta__btn {
  padding: 10px 16px;
  font-size: 14px;
}

/* Placeholders */

.ph {
  margin: 0;
}

.ph__box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 1px solid var(--ph-line);
  background: var(--ph-bg);
  color: #333;
}

.ph__type {
  color: #222;
  font: 600 10px/1.2 var(--font-mono);
  letter-spacing: 0.04em;
}

.ph__meta {
  color: #555;
  font: 400 10px/1.3 var(--font-mono);
  letter-spacing: 0.02em;
}

.ph__caption {
  margin-top: 8px;
  color: #666;
  font: 400 10px/1.4 var(--font-mono);
}

.ph--vector .ph__box {
  aspect-ratio: 5 / 4;
}

.ph--shot .ph__box {
  aspect-ratio: 16 / 10;
}

.ph--photo .ph__box {
  aspect-ratio: 4 / 5;
}

.ph--icon .ph__box {
  width: 96px;
  height: 96px;
  gap: 6px;
}

.ph--icon .ph__type {
  font-size: 8px;
  letter-spacing: 0.04em;
}

.ph--icon .ph__meta {
  font-size: 8px;
}

/* 01. Hero */

.hero {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  align-items: start;
}

.hero__copy {
  grid-column: span 7;
}

.hero__copy .h1 {
  max-width: 660px;
}

.hero__lead {
  max-width: 590px;
  margin-top: 28px;
}

.hero__audience {
  max-width: 590px;
  margin-top: 24px;
  color: var(--muted);
}

.hero__action {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: 44px;
}

.hero__visual {
  grid-column: span 5;
}

/* 02. Audience */

.audience {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.audience__col {
  grid-column: span 6;
  padding-top: 24px;
  border-top: 1px solid var(--line-strong);
}

.audience .h3 {
  margin-bottom: 24px;
}

.marker-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding-left: 22px;
  list-style: square outside;
  font-size: 18px;
  line-height: 1.55;
}

.marker-list li::marker {
  color: #444;
}

.marker-list--no {
  list-style-type: circle;
  color: #444;
}

/* 03. Scenarios */

.scenario-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.scenario-group {
  grid-column: span 6;
  padding: 28px 28px 32px;
  background: #fafafa;
}

.scenario-group .h3 {
  padding-bottom: 16px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.scenario p {
  font-size: 18px;
  line-height: 1.55;
}

.scenario strong {
  font-weight: 600;
}

.scenario + .scenario {
  padding-top: 24px;
  margin-top: 24px;
  border-top: 1px solid var(--line-soft);
}

/* 04. Process */

.steps {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  list-style: none;
  counter-reset: step;
}

.steps li {
  grid-column: span 4;
  padding-top: 20px;
  border-top: 1px solid var(--line-strong);
  counter-increment: step;
}

.steps li::before {
  content: "0" counter(step);
  display: block;
  margin-bottom: 24px;
  color: var(--ink);
  font: 600 32px/1 var(--font-mono);
  letter-spacing: -0.04em;
}

.steps .h3 {
  margin-bottom: 16px;
}

.steps p {
  font-size: 18px;
  line-height: 1.55;
}

.note {
  max-width: 820px;
  padding-top: 24px;
  margin-top: 48px;
  border-top: 1px solid #b5b5b5;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.5;
}

/* 05. Proof */

.proof-intro {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  margin-bottom: 48px;
}

.proof-intro .h3 {
  grid-column: span 4;
}

.proof-intro p {
  grid-column: span 8;
  font-size: 18px;
  line-height: 1.55;
}

.projects .h3 {
  margin-bottom: 8px;
}

.projects__intro {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.5;
}

.project-list {
  margin-top: 24px;
  border-top: 1px solid var(--line-strong);
  list-style: none;
}

.project {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  align-items: center;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.project:last-child {
  border-bottom: 0;
}

.project__shot {
  grid-column: span 3;
}

.project__body {
  grid-column: span 9;
}

.project__name {
  margin-bottom: 8px;
  color: var(--black);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.35;
}

.project__desc {
  max-width: 620px;
  color: #444;
  font-size: 15px;
  line-height: 1.5;
}

.project__link {
  display: inline-block;
  margin-top: 10px;
  color: var(--ink);
  font: 400 12px/1.4 var(--font-mono);
}

.proof-statement {
  max-width: 860px;
  padding-top: 28px;
  margin-top: 40px;
  border-top: 1px solid var(--line-strong);
  color: var(--muted);
  font-size: 15px;
  font-weight: 400;
  line-height: 1.5;
}

.experience {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  align-items: start;
  margin-bottom: 48px;
}

.experience > .h3 {
  grid-column: span 4;
}

.experience > p {
  grid-column: span 8;
  font-size: 18px;
  line-height: 1.55;
}

/* 06. Limits */

.limits {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.limits p {
  grid-column: span 4;
  padding-top: 24px;
  border-top: 1px solid var(--line-strong);
  font-size: 18px;
  line-height: 1.55;
}

.limits strong {
  font-weight: 600;
}

/* 07. FAQ */

.faq {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  column-gap: 24px;
  row-gap: 0;
}

.faq__item {
  grid-column: span 6;
  padding: 24px 0 32px;
  border-top: 1px solid var(--line-strong);
}

.faq dt {
  color: var(--black);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.35;
}

.faq dd {
  max-width: 520px;
  margin-top: 12px;
  color: #333;
  font-size: 18px;
  line-height: 1.55;
}

/* 08. About */

.about {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
  align-items: start;
}

.about__text {
  grid-column: span 8;
  max-width: 700px;
  font-size: 18px;
  line-height: 1.55;
}

.block--about {
  position: relative;
  overflow: hidden;
}

.about__photo {
  position: absolute;
  right: 24px;
  bottom: 0;
  width: 300px;
}

.about__photo--mobile {
  display: none;
}

.about__figure {
  position: relative;
  width: 100%;
  aspect-ratio: 4 / 5;
  overflow: hidden;
}

.about__figure::before {
  content: "";
  position: absolute;
  top: 8%;
  left: 50%;
  width: 30%;
  aspect-ratio: 1;
  border-radius: 50%;
  background: #d8d8d8;
  transform: translateX(-50%);
}

.about__figure::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 84%;
  height: 68%;
  border-radius: 50% 50% 0 0;
  background: #d8d8d8;
  transform: translateX(-50%);
}

.about__photo-label {
  position: absolute;
  top: 50%;
  left: 50%;
  z-index: 1;
  transform: translate(-50%, -50%);
}

/* 09. Final CTA */

.block--cta {
  position: relative;
  z-index: 2;
  border-top: 1px solid var(--ink);
  background: var(--ink);
  color: #fff;
}

.block--cta .block__inner {
  padding-top: 112px;
  padding-bottom: 112px;
}

.block--cta .block__label {
  border-bottom-color: #3a3a3a;
  color: #9a9a9a;
}

.block--cta .block__number,
.block--cta .block__code {
  color: #fff;
}

.block--cta .block__number::after {
  color: #777;
}

.block--cta .block__role,
.block--cta .block__spec {
  color: #9a9a9a;
}

.block--cta .h2 {
  max-width: 900px;
  color: #fff;
}

.cta__lead {
  max-width: 680px;
  margin-top: 24px;
  color: #c7c7c7;
}

.cta__action {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: 40px;
}

/* Prototype-only clean mode */

.mode-toggle__input {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.mode-bar {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 100;
  display: flex;
  align-items: center;
  max-width: calc(100vw - 32px);
  padding: 10px 14px;
  border: 1px solid var(--ink);
  background: #fff;
  color: var(--ink);
  font: 400 10px/1.2 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.mode-bar__label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.mode-bar__mark {
  position: relative;
  display: block;
  flex: none;
  width: 12px;
  height: 12px;
  border: 1px solid currentColor;
}

#clean-mode:checked ~ .mode-bar .mode-bar__mark::after {
  content: "";
  position: absolute;
  inset: 2px;
  background: currentColor;
}

#clean-mode:focus-visible ~ .mode-bar .mode-bar__label {
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}

#clean-mode:checked ~ .sheet .spec {
  visibility: hidden;
  height: 0;
  min-height: 0;
  overflow: hidden;
  border-bottom: 0;
}

#clean-mode:checked ~ .sheet .guides,
#clean-mode:checked ~ .sheet .ph__meta,
#clean-mode:checked ~ .sheet .ph__caption,
#clean-mode:checked ~ .sheet .tech-note {
  visibility: hidden;
}

#clean-mode:checked ~ .sheet .block__label {
  visibility: hidden;
  height: 0;
  padding: 0;
  margin: 0;
  border: 0;
  overflow: hidden;
}

@media (max-width: 900px) {
  body {
    padding: 0;
  }

  .mode-bar {
    right: 16px;
    bottom: 16px;
  }

  .sticky-cta__inner {
    padding: 10px 20px;
  }

  .sticky-cta__title {
    font-size: 16px;
  }

  .sticky-cta__btn {
    padding: 9px 12px;
    font-size: 13px;
  }

  .about__photo {
    display: none;
  }

  .about__photo--mobile {
    display: block;
    position: relative;
    right: auto;
    bottom: auto;
    width: 100%;
    max-width: 300px;
    margin-top: 8px;
  }

  .about {
    margin-bottom: -64px;
  }

  .sheet {
    outline: 0;
  }

  .spec__bar {
    padding: 10px 20px;
  }

  .spec__body {
    grid-template-columns: 1fr;
    gap: 0;
    padding: 20px;
  }

  .spec__col {
    grid-column: auto;
    padding: 20px 0;
    border-top: 1px solid #d0d0d0;
  }

  .spec__col:first-child {
    padding-top: 0;
    border-top: 0;
  }

  .spec__col + .spec__col {
    padding-left: 0;
    border-left: 0;
  }

  .spec__foot {
    padding: 12px 20px;
  }

  .guides {
    right: 20px;
    left: 20px;
  }

  .block__inner {
    padding: 64px 20px;
  }

  .block--cta .block__inner {
    padding-top: 80px;
    padding-bottom: 80px;
  }

  .hero,
  .audience,
  .scenario-grid,
  .steps,
  .proof-intro,
  .project,
  .experience,
  .limits,
  .faq,
  .about,
  .section-head {
    grid-template-columns: 1fr;
  }

  .hero > *,
  .audience > *,
  .scenario-grid > *,
  .steps > *,
  .proof-intro > *,
  .project > *,
  .experience > *,
  .limits > *,
  .faq > *,
  .about > *,
  .section-head > * {
    grid-column: 1 / -1;
  }

  .hero__visual {
    max-width: 420px;
  }

  .project__shot {
    max-width: 320px;
  }

  .section-head {
    margin-bottom: 32px;
  }
}

@media (max-width: 640px) {
  .h1 {
    font-size: 42px;
  }

  .hero__copy .h1 {
    font-size: min(42px, 10.2vw);
  }

  .h2 {
    font-size: 30px;
  }

  .h3 {
    font-size: 21px;
  }

  .lead {
    font-size: 18px;
  }

  .block__inner {
    padding: 48px 20px;
  }

  .block--cta .block__inner {
    padding: 64px 20px;
  }

  .about {
    margin-bottom: -48px;
  }

  .hero__action,
  .cta__action {
    align-items: flex-start;
  }
}