.tutorial-page {
  background:
    linear-gradient(90deg, transparent 0 49.9%, var(--color-border-faint) 49.9% 50%, transparent 50%),
    radial-gradient(circle at 82% 9%, var(--color-warning-soft), transparent 28%),
    var(--color-bg);
}

.tutorial-hero {
  min-height: calc(680px - var(--header-height));
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(420px, 0.78fr);
  align-items: center;
  gap: clamp(42px, 7vw, 104px);
}

.tutorial-hero-copy {
  min-width: 0;
}

.tutorial-hero-copy .kicker {
  margin-bottom: 24px;
}

.tutorial-hero-copy h1 {
  max-width: 8em;
}

.tutorial-hero-copy .lead {
  margin: 26px 0 0;
}

.tutorial-hero-copy .button-row {
  margin-top: 30px;
}

.tutorial-thread {
  min-width: 0;
  padding: clamp(30px, 5vw, 64px);
  position: relative;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  background:
    repeating-linear-gradient(0deg, transparent 0 29px, var(--color-border-faint) 29px 30px),
    repeating-linear-gradient(90deg, transparent 0 29px, var(--color-border-faint) 29px 30px),
    var(--color-panel);
  box-shadow: var(--shadow-device);
  transform: rotate(0.4deg);
}

.tutorial-thread::before,
.tutorial-thread::after {
  position: absolute;
  z-index: -1;
  content: "";
  border: 1px solid var(--color-border);
  background: var(--color-panel-secondary);
}

.tutorial-thread::before {
  inset: 10px -9px -9px 10px;
}

.tutorial-thread::after {
  inset: 20px -17px -17px 20px;
  opacity: 0.45;
}

.thread-heading {
  margin-bottom: clamp(54px, 8vw, 92px);
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
}

.thread-heading span {
  color: var(--color-accent-dark);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.thread-heading strong {
  font-family: var(--font-display);
  font-size: clamp(25px, 3vw, 38px);
}

.thread-track {
  display: flex;
  align-items: center;
}

.thread-knot {
  width: 24px;
  height: 24px;
  flex: 0 0 auto;
  border: 6px solid var(--color-panel);
  border-radius: var(--radius-pill);
  box-shadow: 0 0 0 2px var(--color-border);
}

.thread-knot.is-accent {
  background: var(--color-accent);
}

.thread-knot.is-warning {
  background: var(--color-warning);
}

.thread-knot.is-success {
  background: var(--color-success);
  box-shadow: 0 0 0 2px var(--color-success), 0 0 0 9px var(--color-success-soft);
}

.thread-line {
  height: 4px;
  flex: 1;
  background:
    repeating-linear-gradient(90deg, var(--color-accent) 0 12px, var(--color-warning) 12px 24px);
}

.thread-labels {
  margin-top: 22px;
  display: flex;
  justify-content: space-between;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
}

.tutorial-document {
  padding-bottom: var(--section-space);
}

.tutorial-document .toc-tabs {
  width: 100%;
}

.tutorial-flow {
  width: 100%;
  max-width: var(--reading-width);
  margin-inline: auto;
  padding-top: clamp(42px, 7vw, 78px);
}

.tutorial-flow > .callout:first-child {
  margin-top: 0;
}

.tutorial-stage {
  padding-top: clamp(62px, 9vw, 108px);
  position: relative;
}

.tutorial-stage + .tutorial-stage {
  border-top: 1px solid var(--color-border);
}

.stage-heading {
  margin-bottom: 30px;
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}

.stage-mark {
  width: 24px;
  height: 24px;
  margin-top: 6px;
  position: relative;
  border: 2px solid var(--color-accent);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  box-shadow: 0 0 0 7px var(--color-accent-soft);
}

.stage-mark::after {
  width: 8px;
  height: 8px;
  position: absolute;
  inset: 6px;
  content: "";
  border-radius: var(--radius-pill);
  background: var(--color-accent);
}

.stage-label {
  margin-bottom: 7px;
  color: var(--color-accent-dark);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.stage-heading h2 {
  margin-bottom: 0;
  font-size: clamp(31px, 4vw, 45px);
}

.tutorial-stage > p,
.platform-instruction p,
.completion-panel p {
  color: var(--color-text-muted);
}

.tutorial-stage > p {
  font-size: 1.04rem;
  line-height: 1.85;
}

.stage-action {
  margin-top: 30px;
  padding-top: 22px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 22px;
  border-top: 1px dashed var(--color-border);
}

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

.platform-instructions {
  margin-top: 38px;
  display: grid;
  gap: 20px;
}

.platform-instruction {
  min-width: 0;
  padding: clamp(24px, 4vw, 38px);
  position: relative;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xs);
  background:
    linear-gradient(115deg, var(--color-paper-glow), transparent),
    var(--color-panel);
  box-shadow: 6px 6px 0 var(--color-panel-secondary);
}

.platform-instruction::after {
  width: 110px;
  height: 4px;
  position: absolute;
  right: -18px;
  bottom: 18px;
  content: "";
  background: repeating-linear-gradient(90deg, var(--color-accent) 0 14px, var(--color-warning) 14px 28px);
  transform: rotate(-4deg);
}

.platform-heading {
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 15px;
}

.platform-heading h3 {
  margin-bottom: 0;
  font-family: var(--font-body);
  font-size: 1.25rem;
}

.platform-glyph {
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  color: var(--color-panel);
  border-radius: var(--radius-sm);
  background: var(--color-accent-dark);
  box-shadow: 4px 4px 0 var(--color-warning-soft);
}

.platform-glyph svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.verification-list {
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
  list-style: none;
}

.verification-list li {
  padding: 17px 18px 17px 44px;
  position: relative;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  background: var(--color-panel);
}

.verification-list li::before {
  position: absolute;
  top: 17px;
  left: 17px;
  color: var(--color-success);
  content: "✓";
  font-weight: 800;
}

.verification-list strong {
  color: var(--color-text);
}

.completion-panel {
  margin-top: 44px;
  padding: clamp(28px, 5vw, 48px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 34px;
  border: 1px solid var(--color-border);
  border-left: 6px solid var(--color-success);
  border-radius: var(--radius-xs);
  background:
    repeating-linear-gradient(90deg, transparent 0 24px, var(--color-border-faint) 24px 25px),
    var(--color-panel);
  box-shadow: var(--shadow-card);
}

.completion-panel h3 {
  margin-top: 18px;
}

.completion-panel p {
  margin-bottom: 0;
}

.completion-panel .button-row {
  max-width: 190px;
}

.completion-panel .button {
  width: 100%;
}

@media (max-width: 900px) {
  .tutorial-hero {
    min-height: auto;
    grid-template-columns: 1fr;
  }

  .tutorial-thread {
    width: min(100%, 620px);
    transform: none;
  }

  .completion-panel {
    grid-template-columns: 1fr;
  }

  .completion-panel .button-row {
    max-width: none;
  }
}

@media (max-width: 640px) {
  .tutorial-hero {
    gap: 52px;
  }

  .tutorial-thread {
    padding: 24px 18px;
  }

  .tutorial-thread::before,
  .tutorial-thread::after {
    display: none;
  }

  .thread-heading {
    margin-bottom: 48px;
  }

  .thread-heading strong {
    font-size: 24px;
  }

  .thread-knot {
    width: 18px;
    height: 18px;
    border-width: 4px;
  }

  .thread-line {
    height: 3px;
  }

  .thread-labels {
    font-size: 0.62rem;
  }

  .tutorial-flow {
    padding-top: 38px;
  }

  .tutorial-stage {
    padding-top: 68px;
  }

  .stage-heading {
    grid-template-columns: 22px minmax(0, 1fr);
    gap: 13px;
  }

  .stage-mark {
    width: 19px;
    height: 19px;
    margin-top: 7px;
    box-shadow: 0 0 0 5px var(--color-accent-soft);
  }

  .stage-mark::after {
    width: 7px;
    height: 7px;
    inset: 4px;
  }

  .platform-instruction {
    padding: 22px 18px;
    box-shadow: 4px 4px 0 var(--color-panel-secondary);
  }

  .platform-instruction::after {
    display: none;
  }

  .stage-action {
    align-items: stretch;
  }

  .stage-action .button {
    width: 100%;
  }

  .completion-panel {
    padding: 24px 18px;
    box-shadow: 5px 5px 0 var(--color-panel-secondary);
  }
}