:root {
  --accent: #0071e3;
  --accent-deep: #0058b0;
  --ink: #1d1d1f;
  --paper: #f5f5f7;
  --muted: #6e6e73;
  --line: rgba(29, 29, 31, .14);
}

body {
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "PingFang SC", "Noto Sans SC Variable", sans-serif;
}

.tutorial-container {
  width: min(1080px, calc(100vw - 80px));
  margin: 0 auto;
}

.tutorial-hero {
  overflow: hidden;
  padding: 96px 0 88px;
  background:
    radial-gradient(circle at 82% 14%, rgba(0, 113, 227, .15), transparent 34%),
    linear-gradient(180deg, #fff 0%, #f5f5f7 100%);
}

.tutorial-breadcrumb {
  margin-bottom: 56px;
  color: var(--muted);
  font-size: 12px;
}

.tutorial-breadcrumb a:hover { color: var(--accent); }

.tutorial-kicker {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .09em;
}

.tutorial-hero h1 {
  max-width: none;
  margin: 0;
  font-size: clamp(52px, 7vw, 82px);
  line-height: 1;
  letter-spacing: -.065em;
}

.tutorial-hero h1 span {
  display: block;
  margin-top: 18px;
  font-size: .48em;
  line-height: 1.12;
  letter-spacing: -.045em;
}

.tutorial-lead {
  max-width: 760px;
  margin: 28px 0 0;
  color: #424245;
  font-size: clamp(18px, 2.1vw, 24px);
  line-height: 1.6;
  letter-spacing: -.018em;
}

.tutorial-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 32px;
}

.tutorial-meta span {
  padding: 8px 12px;
  border-radius: 999px;
  color: #424245;
  background: rgba(0, 0, 0, .055);
  font-size: 12px;
  font-weight: 600;
}

.tutorial-section {
  padding: 92px 0;
  border-top: 1px solid var(--line);
}

.tutorial-section-white { background: #fff; }

.tutorial-section-head {
  max-width: 760px;
  margin-bottom: 44px;
}

.tutorial-section-index {
  margin: 0 0 15px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .09em;
}

.tutorial-section h2 {
  margin: 0;
  font-size: clamp(36px, 5vw, 60px);
  line-height: 1.08;
  letter-spacing: -.05em;
}

.tutorial-section-lead {
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.8;
}

.video-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  align-items: stretch;
  gap: 18px;
}

.video-stage {
  min-height: 760px;
  display: grid;
  place-items: center;
  padding: 24px;
  border-radius: 32px;
  background: #09090b;
  box-shadow: 0 28px 80px rgba(0, 0, 0, .16);
}

.video-stage video {
  display: block;
  width: auto;
  max-width: 100%;
  height: min(720px, 78vh);
  max-height: 720px;
  border-radius: 20px;
  background: #000;
}

.video-chapters {
  display: flex;
  flex-direction: column;
  padding: 28px;
  border-radius: 32px;
  background: #fff;
}

.video-chapters h3 {
  margin: 0 0 8px;
  font-size: 24px;
  letter-spacing: -.035em;
}

.video-chapters > p {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

.chapter-list {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.chapter-button {
  width: 100%;
  min-height: 62px;
  display: grid;
  grid-template-columns: 50px 1fr;
  align-items: center;
  gap: 12px;
  padding: 0;
  color: var(--ink);
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--line);
  text-align: left;
  cursor: pointer;
  transition: color .16s ease, transform 90ms ease-out;
}

.chapter-button:hover { color: var(--accent); }
.chapter-button:active { transform: scale(.98); }
.chapter-button span { color: var(--accent); font-size: 11px; font-variant-numeric: tabular-nums; }
.chapter-button strong { font-size: 14px; }

.video-note {
  margin: auto 0 0;
  padding-top: 24px;
  color: var(--muted);
  font-size: 11px;
  line-height: 1.7;
}

.quick-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.quick-card {
  min-height: 260px;
  padding: 30px;
  border-radius: 26px;
  background: var(--paper);
}

.quick-card > span {
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
}

.quick-card h3 {
  margin: 70px 0 12px;
  font-size: 23px;
  line-height: 1.22;
  letter-spacing: -.035em;
}

.quick-card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.mode-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.mode-card {
  padding: 34px;
  border-radius: 28px;
  background: #fff;
}

.mode-card-dark {
  color: #f5f5f7;
  background: #1d1d1f;
}

.mode-card .mode-label {
  margin: 0 0 36px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
}

.mode-card h3 {
  margin: 0 0 24px;
  font-size: clamp(28px, 3vw, 38px);
  letter-spacing: -.045em;
}

.mode-card ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: mode;
}

.mode-card li {
  counter-increment: mode;
  display: grid;
  grid-template-columns: 36px 1fr;
  gap: 12px;
  padding: 17px 0;
  border-top: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.75;
}

.mode-card li::before {
  content: counter(mode, decimal-leading-zero);
  color: var(--accent);
  font-size: 11px;
  font-weight: 700;
}

.mode-card-dark li { border-color: rgba(255, 255, 255, .14); }
.mode-card-dark li div { color: #d2d2d7; }

.copy-steps {
  min-height: 46px;
  margin-top: 24px;
  padding: 0 17px;
  color: #fff;
  background: var(--accent);
  border: 0;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 650;
  cursor: pointer;
  transition: transform 90ms ease-out, background-color .16s ease;
}

.copy-steps:hover { background: #0077ed; }
.copy-steps:active { transform: scale(.97); }

.copy-status {
  min-height: 18px;
  margin: 10px 0 0;
  color: var(--accent);
  font-size: 12px;
}

.transcript-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.transcript-list li {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 28px;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.transcript-list time {
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.transcript-list p {
  margin: 0;
  color: #424245;
  font-size: 15px;
  line-height: 1.8;
}

.tutorial-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 36px;
  padding: 38px;
  border-radius: 30px;
  color: #f5f5f7;
  background: #1d1d1f;
}

.tutorial-cta h2 {
  font-size: clamp(30px, 4vw, 48px);
}

.tutorial-cta p {
  margin: 12px 0 0;
  color: #a1a1a6;
  font-size: 13px;
  line-height: 1.8;
}

.tutorial-actions {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 10px;
}

.tutorial-action {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 17px;
  border-radius: 999px;
  color: #fff;
  background: var(--accent);
  font-size: 13px;
  font-weight: 650;
  transition: transform 90ms ease-out, background-color .16s ease;
}

.tutorial-action-secondary {
  color: #2997ff;
  background: rgba(41, 151, 255, .12);
}

.tutorial-action:hover { background: #0077ed; }
.tutorial-action-secondary:hover { background: rgba(41, 151, 255, .2); }
.tutorial-action:active { transform: scale(.97); }

.tutorial-foot {
  padding: 34px max(24px, calc((100vw - 1080px) / 2));
  color: #86868b;
  background: #161618;
  font-size: 11px;
  line-height: 1.8;
}

.tutorial-foot-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 12px;
  color: #d2d2d7;
}

.tutorial-foot a:hover { color: #fff; }

@media (max-width: 900px) {
  .video-layout { grid-template-columns: 1fr; }
  .video-stage { min-height: 680px; }
  .video-chapters { min-height: 0; }
  .video-note { margin-top: 24px; }
  .quick-grid { grid-template-columns: 1fr; }
  .quick-card { min-height: 210px; }
  .quick-card h3 { margin-top: 48px; }
}

@media (max-width: 680px) {
  .tutorial-container { width: calc(100vw - 40px); }
  .tutorial-hero { padding: 72px 0 62px; }
  .tutorial-breadcrumb { margin-bottom: 42px; }
  .tutorial-hero h1 { font-size: clamp(48px, 14vw, 64px); }
  .tutorial-lead { font-size: 18px; }
  .tutorial-section { padding: 70px 0; }
  .video-stage { min-height: 0; padding: 12px; border-radius: 24px; }
  .video-stage video { width: 100%; height: auto; max-height: none; border-radius: 16px; }
  .video-chapters { padding: 24px; border-radius: 24px; }
  .mode-grid { grid-template-columns: 1fr; }
  .mode-card { padding: 27px 24px; }
  .transcript-list li { grid-template-columns: 58px 1fr; gap: 14px; }
  .tutorial-cta { align-items: flex-start; flex-direction: column; padding: 30px 24px; }
  .tutorial-actions { width: 100%; align-items: stretch; flex-direction: column; }
  .tutorial-action { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  .chapter-button,
  .copy-steps,
  .tutorial-action { transition-duration: .01ms !important; }
}