/* TAISK Ledger: petrol ink on drafting paper, hairlines instead of shadows. */

:root {
  --bg: #f6f8f9;
  --surface: #ffffff;
  --ink: #161e22;
  --ink-soft: #35424a;
  --muted: #5d696f;
  --primary: #145752;
  --primary-ink: #0f4743;
  --live: #deedec;
  --accent: #e9f1f1;
  --border: #d9dfe2;
  --border-strong: #c3ccd0;
  --radius-control: 0.5rem;
  --radius-card: 0.75rem;
  --radius-panel: 1rem;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --font: "Instrument Sans", "Inter", system-ui, -apple-system, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, monospace;
  --topbar-h: 76px;
  --controls-h: 104px;
  --shadow-shot: 0 18px 44px -28px rgba(18, 32, 38, 0.3), 0 2px 6px rgba(18, 32, 38, 0.05);
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: var(--primary); text-underline-offset: 2px; }
button { font: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
  border-radius: 4px;
}

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.skip {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 60;
  background: var(--ink);
  color: #fff;
  padding: 10px 18px;
  border-radius: var(--radius-control);
  text-decoration: none;
  transition: top 0.18s var(--ease);
}
.skip:focus-visible { top: 12px; }

.icon {
  width: 18px;
  height: 18px;
  flex: none;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ---------- Top bar ---------- */

.topbar {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 30;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid var(--border);
}

.topbar__inner {
  height: var(--topbar-h);
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand { display: flex; align-items: center; border-radius: 6px; }
.brand img { height: 34px; width: auto; }

.topbar__rule {
  width: 1px;
  height: 26px;
  background: var(--border);
}

.topbar__titles { min-width: 0; }
.topbar__kicker {
  margin: 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--primary);
}
.topbar__doc {
  margin: 1px 0 0;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-soft);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.topbar__right {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 16px;
}

.counter {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.ghostbtn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 38px;
  padding: 0 14px;
  border: 1px solid var(--border);
  background: var(--surface);
  border-radius: var(--radius-control);
  font-size: 13.5px;
  font-weight: 500;
  color: var(--ink-soft);
  cursor: pointer;
  transition: border-color 0.16s var(--ease), background 0.16s var(--ease);
}
.ghostbtn:hover { border-color: var(--border-strong); background: var(--accent); }
.ghostbtn .icon { width: 16px; height: 16px; }

.rail {
  height: 3px;
  background: var(--border);
  overflow: hidden;
}
.rail__fill {
  display: block;
  height: 100%;
  width: 0;
  background: var(--primary);
  transition: width 0.45s var(--ease);
}

/* ---------- Stage ---------- */

main {
  padding-top: var(--topbar-h);
  padding-bottom: calc(var(--controls-h) + 8px);
  min-height: 100vh;
  min-height: 100dvh;
}

.slide { display: none; }
.js .slide { animation: slideIn 0.4s var(--ease) both; }
.slide.is-active { display: block; }

@keyframes slideIn {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: none; }
}

.slide__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 44px 40px 56px;
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: 56px;
  align-items: center;
  align-content: safe center;
  min-height: calc(100vh - var(--topbar-h) - var(--controls-h) - 40px);
  min-height: calc(100dvh - var(--topbar-h) - var(--controls-h) - 40px);
}

/* ---------- Copy column ---------- */

.eyebrow {
  margin: 0 0 14px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--primary);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
}

h1, h2, h3 { letter-spacing: -0.022em; text-wrap: balance; }

h1.display {
  margin: 0 0 22px;
  font-size: clamp(2.35rem, 4.15vw, 3.85rem);
  line-height: 1.02;
  font-weight: 600;
}
.display--sm { font-size: clamp(2.1rem, 4vw, 3rem); }

h2 {
  margin: 0 0 16px;
  font-size: clamp(1.85rem, 3.15vw, 2.7rem);
  line-height: 1.1;
  font-weight: 600;
  max-width: 15ch;
}

h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 600;
}

.lead {
  margin: 0 0 26px;
  font-size: 1.075rem;
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 46ch;
}

.tasks {
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  counter-reset: task;
  display: grid;
  gap: 14px;
  max-width: 48ch;
}

.tasks li {
  position: relative;
  counter-increment: task;
  padding-left: 40px;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--ink-soft);
}

.tasks li::before {
  content: counter(task);
  position: absolute;
  left: 0;
  top: 1px;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--surface);
  border: 1px solid var(--border-strong);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--primary);
}

.ui {
  display: inline-block;
  padding: 1px 7px 2px;
  border-radius: 6px;
  background: var(--accent);
  border: 1px solid #d3e4e3;
  color: var(--primary-ink);
  font-size: 0.925em;
  font-weight: 500;
  white-space: nowrap;
}

.tip {
  margin: 0;
  padding: 14px 18px;
  border-left: 3px solid var(--primary);
  background: var(--live);
  border-radius: 0 var(--radius-control) var(--radius-control) 0;
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 50ch;
}
.tip__label {
  display: inline-block;
  margin-right: 8px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--primary);
}

/* ---------- Screenshot column ---------- */

.shot {
  margin: 0;
  min-width: 0;
}

.shot__btn {
  display: block;
  width: 100%;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  background: var(--surface);
  overflow: hidden;
  cursor: zoom-in;
  box-shadow: var(--shadow-shot);
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), border-color 0.25s var(--ease);
}
.shot__btn:hover {
  transform: translateY(-2px);
  border-color: var(--border-strong);
  box-shadow: 0 26px 56px -30px rgba(18, 32, 38, 0.38), 0 2px 8px rgba(18, 32, 38, 0.06);
}
.shot__btn img {
  width: 100%;
  height: auto;
  max-height: min(60vh, 560px);
  object-fit: contain;
  object-position: center;
  background: var(--surface);
}

.shot figcaption {
  margin-top: 12px;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.02em;
  color: var(--muted);
}
.shot__hint { color: var(--primary); }

/* ---------- Cover ---------- */

.cover {
  grid-template-columns: minmax(0, 1.04fr) minmax(0, 1fr);
  gap: 56px;
}

.cover__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 34px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  height: 30px;
  padding: 0 13px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  font-size: 12.5px;
  color: var(--muted);
}
.chip .icon { width: 14px; height: 14px; }

.cover__actions { margin-bottom: 20px; }

.hint {
  margin: 0;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.02em;
  color: var(--muted);
}

kbd {
  display: inline-block;
  min-width: 20px;
  padding: 1px 6px;
  border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  border-radius: 5px;
  background: var(--surface);
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-soft);
  text-align: center;
}

.cover__thumbs {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.thumb {
  margin: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius-control);
  background: var(--surface);
  overflow: hidden;
  transition: transform 0.28s var(--ease), border-color 0.28s var(--ease);
}
.thumb:hover { transform: translateY(-3px); border-color: var(--border-strong); }
.thumb img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: top center;
  border-bottom: 1px solid var(--border);
}
.thumb figcaption {
  padding: 8px 10px 10px;
  font-size: 11.5px;
  line-height: 1.3;
  color: var(--muted);
  display: flex;
  gap: 7px;
}
.thumb figcaption b {
  font-family: var(--mono);
  font-weight: 500;
  color: var(--primary);
}
.thumb--end {
  grid-column: span 2;
  display: grid;
  place-items: center;
  background: var(--accent);
  border-style: dashed;
  min-height: 84px;
}
.thumb--end figcaption {
  color: var(--primary);
  font-family: var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 10.5px;
}

/* ---------- Done ---------- */

.slide--done .slide__inner,
.done {
  grid-template-columns: minmax(0, 1fr);
  justify-items: start;
  max-width: 780px;
  min-height: auto;
  row-gap: 0;
  padding-block: clamp(36px, 7vh, 80px);
}

.recap {
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.recap a {
  display: inline-block;
  padding: 7px 13px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--ink-soft);
  font-size: 13.5px;
  text-decoration: none;
  transition: border-color 0.16s var(--ease), color 0.16s var(--ease);
}
.recap a:hover { border-color: var(--primary); color: var(--primary-ink); }

.done__panel {
  width: 100%;
  margin-bottom: 26px;
  padding: 20px 22px;
  border: 1px solid var(--border);
  border-radius: var(--radius-panel);
  background: var(--surface);
}
.done__panel p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--muted);
  max-width: 54ch;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  border-radius: var(--radius-control);
  border: 1px solid transparent;
  cursor: pointer;
  font-weight: 500;
  transition: background 0.16s var(--ease), border-color 0.16s var(--ease), color 0.16s var(--ease), opacity 0.16s var(--ease);
}

.btn--lg {
  height: 52px;
  padding: 0 26px;
  font-size: 1rem;
}

.btn--primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 10px 24px -14px rgba(20, 87, 82, 0.7);
}
.btn--primary:hover { background: var(--primary-ink); }

.btn--ghost {
  background: var(--surface);
  border-color: var(--border);
  color: var(--ink-soft);
  height: 44px;
  padding: 0 18px;
  font-size: 0.95rem;
}
.btn--ghost:hover { border-color: var(--border-strong); background: var(--accent); }

/* ---------- Controls ---------- */

.controls {
  position: fixed;
  inset: auto 0 0 0;
  z-index: 30;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-top: 1px solid var(--border);
  padding: 12px 0 8px;
}

.controls__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 20px;
}

.btn--nav {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  height: 56px;
  padding: 0 18px;
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-card);
  color: var(--ink-soft);
  justify-self: start;
  text-align: left;
}
.btn--nav:hover:not(:disabled) { border-color: var(--primary); color: var(--primary-ink); }
.btn--nav:disabled { opacity: 0.42; cursor: default; }
.btn--nav .icon { width: 20px; height: 20px; }

.btn__label {
  display: grid;
  line-height: 1.15;
}
.btn__label small {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--muted);
}
.btn__label span {
  font-size: 14.5px;
  font-weight: 500;
  color: inherit;
}
.btn--next { justify-self: end; text-align: right; }

.dots {
  display: flex;
  align-items: center;
  gap: 2px;
}

.dot {
  position: relative;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border: 0;
  background: none;
  cursor: pointer;
  border-radius: 50%;
}
.dot::after {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 999px;
  background: var(--border-strong);
  transition: width 0.22s var(--ease), background 0.22s var(--ease);
}
.dot:hover::after { background: var(--muted); }
.dot[aria-current="step"]::after {
  width: 24px;
  background: var(--primary);
}
.dot.is-visited::after { background: #a9bcc0; }

.dot__num {
  position: absolute;
  font-family: var(--mono);
  font-size: 10px;
  color: transparent;
}

.controls__hint {
  margin: 6px 0 0;
  text-align: center;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.03em;
  color: #8a969b;
}

/* ---------- Lightbox ---------- */

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 68px 4vw 4vh;
  background: rgba(11, 20, 24, 0.9);
  backdrop-filter: blur(4px);
  animation: fade 0.2s var(--ease);
}
.lightbox[hidden] { display: none; }
.lightbox img {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 40px 90px -40px rgba(0, 0, 0, 0.8);
  object-fit: contain;
}
.lightbox__close {
  position: absolute;
  top: 18px;
  right: 22px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 42px;
  padding: 0 16px;
  border-radius: var(--radius-control);
  border: 1px solid rgba(255, 255, 255, 0.24);
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  font-size: 0.9rem;
  cursor: pointer;
}
.lightbox__close:hover { background: rgba(255, 255, 255, 0.2); }

@keyframes fade { from { opacity: 0; } to { opacity: 1; } }

/* ---------- Overview ---------- */

.overview {
  position: fixed;
  inset: 0;
  z-index: 45;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(11, 20, 24, 0.55);
  backdrop-filter: blur(6px);
  animation: fade 0.2s var(--ease);
}
.overview[hidden] { display: none; }

.overview__panel {
  width: min(1000px, 100%);
  max-height: 88vh;
  overflow: auto;
  background: var(--bg);
  border-radius: var(--radius-panel);
  border: 1px solid var(--border);
  box-shadow: 0 40px 90px -40px rgba(0, 0, 0, 0.5);
}

.overview__head {
  position: sticky;
  top: 0;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 22px;
  background: rgba(246, 248, 249, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.overview__head h2 {
  margin: 0;
  font-size: 1.15rem;
  max-width: none;
}

.overview__grid {
  margin: 0;
  padding: 22px;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(224px, 1fr));
  gap: 14px;
  counter-reset: card;
}

.overview__grid button {
  counter-increment: card;
  width: 100%;
  padding: 0;
  text-align: left;
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  background: var(--surface);
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease);
}
.overview__grid button:hover { transform: translateY(-2px); border-color: var(--primary); }
.overview__grid button[aria-current="step"] { border-color: var(--primary); box-shadow: 0 0 0 2px var(--live); }
.overview__grid img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: top center;
  border-bottom: 1px solid var(--border);
  background: #fff;
}
.overview__grid .card__text {
  padding: 11px 13px 14px;
  display: grid;
  gap: 2px;
}
.overview__grid .card__num {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--primary);
}
.overview__grid .card__title {
  font-size: 13.5px;
  font-weight: 500;
  line-height: 1.3;
  color: var(--ink);
}

/* ---------- Responsive ---------- */

@media (max-width: 1024px) {
  .slide__inner,
  .cover {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
    padding: 32px 28px 48px;
    min-height: 0;
  }
  .shot { order: 2; }
  .copy { order: 1; }
  h2 { max-width: none; }
  .shot__btn img { max-height: none; }
  .cover__thumbs { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .cover__thumbs .thumb:nth-child(7) { display: none; }
  .cover__thumbs .thumb--end { display: none; }
  .topbar__titles { display: none; }
  .topbar__rule { display: none; }
}

@media (max-width: 780px) {
  :root { --topbar-h: 64px; --controls-h: 92px; }
  .brand img { height: 28px; }
  .topbar__inner { padding: 0 18px; gap: 12px; }
  .counter { font-size: 11px; }
  .ghostbtn__label { display: none; }
  .ghostbtn { padding: 0 12px; }

  main { padding-bottom: calc(var(--controls-h) + 16px); }
  .slide__inner { padding: 26px 20px 40px; gap: 26px; }
  h1.display { font-size: clamp(2.2rem, 9vw, 3rem); }
  h2 { font-size: clamp(1.6rem, 7vw, 2.1rem); }
  .lead { font-size: 1rem; margin-bottom: 22px; }
  .tasks { gap: 12px; margin-bottom: 22px; }
  .tasks li { font-size: 0.95rem; padding-left: 36px; }
  .cover__thumbs { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
  .cover__thumbs .thumb:nth-child(7) { display: block; }

  .controls { padding: 10px 0 6px; }
  .controls__inner {
    padding: 0 14px;
    grid-template-columns: 1fr 1fr;
    grid-template-areas: "dots dots" "prev next";
    gap: 10px;
  }
  .dots {
    grid-area: dots;
    justify-content: center;
    order: -1;
  }
  #prev { grid-area: prev; }
  #next { grid-area: next; }
  .btn--nav { height: 52px; width: 100%; justify-content: center; text-align: center; }
  .btn--next { justify-self: stretch; }
  .btn--nav .icon { order: -1; }
  .btn--next .icon { order: 2; }
  .controls__hint { display: none; }
  .lightbox { padding: 64px 12px 12px; }
  .overview { padding: 10px; }
  .overview__grid { padding: 14px; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
  .js .slide { animation: none; }
}

@media print {
  .topbar, .controls, .lightbox, .overview { display: none !important; }
  main { padding: 0; }
  .slide { display: block !important; page-break-after: always; }
  .slide__inner { min-height: 0; grid-template-columns: 1fr; }
}