/* senggack.xyz v2 — Zen Mixed-Media Tutorial Atelier
   palette: Paper Warm / Drafting Cream / Indigo Ink / Drafting Indigo /
            Wax-Pencil Brick / Aged Brass / Bone Page
   type:    Yeseva One (display) + JetBrains Mono (numerals/labels) +
            Lora (body) + Inter (UI captions)
*/

:root {
  --paper-warm:      #F5EFD9;
  --drafting-cream:  #E5D9B8;
  --indigo-ink:      #1F2C5C;
  --drafting-indigo: #3A4F8C;
  --wax-brick:       #A65A3A;
  --aged-brass:      #7E5A2C;
  --bone-page:       #E0D6C2;

  --shadow-paper: 4px 4px 8px rgba(126, 90, 44, 0.30);
  --shadow-paper-soft: 3px 3px 6px rgba(126, 90, 44, 0.22);

  --pad-x: 8vw;
  --stage-min-h: 100vh;

  --t-soft: 600ms cubic-bezier(0.22, 0.61, 0.36, 1);
  --t-slow: 1200ms cubic-bezier(0.22, 0.61, 0.36, 1);

  --font-display: "Yeseva One", "Lora", Georgia, serif;
  --font-body: "Lora", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", monospace;
  --font-ui: "Inter", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--paper-warm);
  color: var(--indigo-ink);
  font-family: var(--font-body);
  font-size: clamp(18px, 1.4vw, 21px);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

html {
  scroll-behavior: smooth;
}

body {
  overflow-x: hidden;
}

.page {
  scroll-snap-type: y mandatory;
  overflow-y: auto;
  height: 100vh;
  scroll-behavior: smooth;
  background:
    radial-gradient(ellipse at 12% 8%, rgba(31, 44, 92, 0.04), transparent 60%),
    radial-gradient(ellipse at 92% 92%, rgba(166, 90, 58, 0.06), transparent 55%),
    var(--paper-warm);
}

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

/* ============================== STAGE BASE ============================== */
.stage {
  position: relative;
  min-height: var(--stage-min-h);
  width: 100%;
  padding: 7vh var(--pad-x);
  scroll-snap-align: start;
  scroll-snap-stop: always;
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
}

.stage::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    repeating-linear-gradient(
      0deg,
      transparent 0 79px,
      rgba(31, 44, 92, 0.025) 79px 80px
    );
  opacity: 0.55;
  mix-blend-mode: multiply;
}

.stage::after {
  /* Subtle paper grain via radial speckle */
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(circle at 25% 30%, rgba(126, 90, 44, 0.05) 0 1px, transparent 1px),
    radial-gradient(circle at 75% 70%, rgba(126, 90, 44, 0.04) 0 1px, transparent 1px),
    radial-gradient(circle at 60% 18%, rgba(126, 90, 44, 0.04) 0 1px, transparent 1px);
  background-size: 9px 11px, 13px 15px, 21px 19px;
  opacity: 0.6;
  mix-blend-mode: multiply;
}

/* ============================== COVER STAGE ============================== */
.stage-cover {
  justify-content: space-between;
  padding-top: 9vh;
  padding-bottom: 7vh;
}

.cover-meta {
  display: flex;
  gap: 1.4rem;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--drafting-indigo);
  z-index: 3;
}

.meta-tag {
  position: relative;
  padding: 0.35rem 0.9rem;
  border: 1px solid rgba(31, 44, 92, 0.18);
  border-radius: 18px;
  background: rgba(245, 239, 217, 0.7);
  backdrop-filter: blur(1px);
}

.meta-tag.mono-tag {
  background: var(--indigo-ink);
  color: var(--bone-page);
  border-color: var(--indigo-ink);
}

.cover-collage {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
}

.paper-shape {
  position: absolute;
  opacity: 0;
}

.paper-triangle {
  width: clamp(160px, 22vw, 360px);
  top: 18vh;
  left: 6vw;
  transform: translate3d(-40px, -30px, 0) rotate(-8deg);
  transition: opacity var(--t-slow), transform var(--t-slow);
}

.paper-crane {
  width: clamp(120px, 14vw, 220px);
  bottom: 14vh;
  right: 10vw;
  transform: translate3d(40px, 40px, 0) rotate(12deg);
  transition: opacity var(--t-slow), transform var(--t-slow);
  transition-delay: 350ms;
}

.photo-card {
  position: absolute;
  border-radius: 2px;
  box-shadow: var(--shadow-paper);
  overflow: hidden;
  opacity: 0;
  filter: sepia(0.25) contrast(1.05);
  transition: opacity var(--t-slow), transform var(--t-slow);
  transition-delay: 200ms;
  background: var(--bone-page);
}

.photo-card svg { display: block; width: 100%; height: 100%; }

.photo-desk {
  top: 40vh;
  right: 14vw;
  width: clamp(220px, 26vw, 420px);
  height: clamp(150px, 18vw, 290px);
  transform: rotate(-2deg) translate3d(20px, 0, 0);
}

.schematic {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.schematic-cover {
  width: 100%;
  height: 100%;
}

.schem-line {
  stroke-dasharray: 1200;
  stroke-dashoffset: 1200;
  transition: stroke-dashoffset 1400ms ease-out;
  transition-delay: 500ms;
}

.schem-dot { opacity: 0; transition: opacity 600ms; transition-delay: 1500ms; }
.schem-label { opacity: 0; transition: opacity 600ms; transition-delay: 1700ms; }

.stage.in-view .schem-line { stroke-dashoffset: 0; }
.stage.in-view .schem-dot,
.stage.in-view .schem-label { opacity: 1; }

.stage.in-view .paper-shape {
  opacity: 1;
  transform: translate3d(0, 0, 0) rotate(0deg);
}
.stage.in-view .paper-triangle {
  transform: translate3d(0, 0, 0) rotate(-3deg);
}
.stage.in-view .paper-crane {
  transform: translate3d(0, 0, 0) rotate(6deg);
}
.stage.in-view .photo-card {
  opacity: 0.85;
  transform: rotate(-1.5deg) translate3d(0, 0, 0);
}

.cover-headline {
  position: relative;
  z-index: 3;
  font-family: var(--font-display);
  font-size: clamp(48px, 11vw, 168px);
  line-height: 0.96;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--indigo-ink);
  font-weight: 400;
}

.letters {
  display: inline-block;
}

.letters .ltr {
  display: inline-block;
  opacity: 0;
  transform: translateY(0.35em);
  transition: opacity 600ms ease, transform 600ms cubic-bezier(0.22, 0.61, 0.36, 1);
}

.letters .ltr.space { width: 0.32em; }

.letters .ltr.lit {
  opacity: 1;
  transform: translateY(0);
}

.cover-deck {
  position: relative;
  z-index: 3;
  font-family: var(--font-body);
  font-size: clamp(18px, 1.5vw, 22px);
  max-width: 56ch;
  color: var(--indigo-ink);
  line-height: 1.7;
  margin: 1.6rem 0 0;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 900ms ease 900ms, transform 900ms ease 900ms;
}

.cover-deck em {
  font-style: italic;
  color: var(--wax-brick);
}

.stage.in-view .cover-deck {
  opacity: 1;
  transform: translateY(0);
}

.cover-foot {
  z-index: 3;
  display: flex;
  gap: 1.2rem;
  align-items: center;
  margin-top: auto;
}

/* ============================== STEP STAGES ============================== */
.stage-step {
  align-items: stretch;
}

.step-grid {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr) minmax(0, 1fr);
  grid-template-rows: 1fr;
  gap: 2.8vw;
  align-items: stretch;
  width: 100%;
  height: 100%;
}

.step-numeral-wrap {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1.1rem;
  position: relative;
}

.step-tag {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--drafting-indigo);
  padding-bottom: 0.4rem;
  border-bottom: 1px solid rgba(31, 44, 92, 0.22);
  display: inline-block;
  width: max-content;
  max-width: 100%;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 600ms ease 200ms, transform 600ms ease 200ms;
}

.step-numeral {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(120px, 22vw, 280px);
  line-height: 0.9;
  letter-spacing: -0.04em;
  color: var(--indigo-ink);
  display: inline-block;
  transform-origin: left center;
  opacity: 0;
  transform: scale(0.96);
  transition: opacity 700ms ease 350ms, transform 700ms cubic-bezier(0.22, 1.4, 0.36, 1) 350ms;
}

.step-numeral-wrap:hover .step-numeral {
  transform: rotate(1deg) scale(1);
}

.step-emblem {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--wax-brick);
  text-transform: uppercase;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 600ms ease 600ms, transform 600ms ease 600ms;
}

.stage.in-view .step-tag,
.stage.in-view .step-emblem {
  opacity: 1;
  transform: translateY(0);
}

.stage.in-view .step-numeral {
  opacity: 1;
  transform: scale(1);
  animation: numeral-overshoot 900ms cubic-bezier(0.22, 1.4, 0.36, 1) 350ms 1;
}

@keyframes numeral-overshoot {
  0%   { transform: scale(0.96); }
  55%  { transform: scale(1.05); }
  100% { transform: scale(1); }
}

/* Visual: mixed-media composition area */
.step-visual {
  position: relative;
  min-height: 50vh;
  align-self: center;
  transition: transform 500ms ease, filter 500ms ease;
}

.step-visual .paper-shape,
.step-visual .photo-card {
  position: absolute;
}

.step-visual .schematic { position: absolute; inset: 0; pointer-events: none; }

/* Step 1 placement */
#step-01 .photo-card-step {
  top: 18%;
  left: 18%;
  width: 60%;
  height: 50%;
  transform: rotate(-2deg) translate3d(0, 0, 0);
}

#step-01 .paper-circle {
  top: 28%;
  right: 4%;
  width: 38%;
  transform: rotate(4deg);
}

/* Step 2 placement */
#step-02 .paper-crane-large {
  top: 20%;
  left: 12%;
  width: 56%;
  transform: rotate(-4deg);
}
#step-02 .photo-card-step-2 {
  bottom: 8%;
  right: 8%;
  width: 50%;
  height: 40%;
  transform: rotate(3deg);
}

/* Step 3 placement */
#step-03 .photo-card-step {
  top: 12%;
  right: 6%;
  width: 60%;
  height: 52%;
  transform: rotate(-3deg);
}

#step-03 .paper-half-circle {
  bottom: 10%;
  left: 6%;
  width: 50%;
  transform: rotate(-6deg);
}

/* Visual hover */
.step-visual:hover {
  transform: scale(1.04);
}

.step-visual:hover::before {
  content: "";
  position: absolute;
  inset: -10px;
  border: 1px solid rgba(31, 44, 92, 0.45);
  border-radius: 4px;
  pointer-events: none;
  animation: glow-in 220ms ease forwards;
}

@keyframes glow-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* Schematic hover highlight */
.step-visual:hover .schem-line {
  stroke: var(--wax-brick);
  filter: drop-shadow(0 0 4px rgba(166, 90, 58, 0.55));
}

/* Step text column */
.step-text {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1.1rem;
  max-width: 56ch;
}

.step-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(36px, 4.6vw, 68px);
  line-height: 1.05;
  margin: 0;
  color: var(--indigo-ink);
  letter-spacing: -0.005em;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 700ms ease 500ms, transform 700ms ease 500ms;
}

.step-lead,
.step-body {
  font-family: var(--font-body);
  font-size: clamp(17px, 1.25vw, 20px);
  line-height: 1.75;
  color: var(--indigo-ink);
  margin: 0;
  opacity: 0;
  transform: translateY(8px);
}

.step-lead { transition: opacity 600ms ease 700ms, transform 600ms ease 700ms; }
.step-body { transition: opacity 600ms ease 850ms, transform 600ms ease 850ms; }

.step-lead em {
  font-style: italic;
  color: var(--wax-brick);
}

.step-aside {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  opacity: 0;
  transition: opacity 600ms ease 1000ms;
}

.aside-rule {
  display: inline-block;
  height: 1px;
  width: 36px;
  background: var(--wax-brick);
}

.aside-text {
  font-family: var(--font-body);
  font-style: italic;
  font-size: 0.94em;
  color: var(--drafting-indigo);
}

.stage.in-view .step-title,
.stage.in-view .step-lead,
.stage.in-view .step-body {
  opacity: 1;
  transform: translateY(0);
}

.stage.in-view .step-aside {
  opacity: 1;
}

/* ============================== REFLECTION STAGES ============================== */
.stage-reflection {
  min-height: 64vh;
  align-items: center;
  justify-content: center;
  padding: 6vh var(--pad-x);
}

.stage-reflection::before,
.stage-reflection::after { opacity: 0; }

.aphorism {
  width: 70vw;
  max-width: 980px;
  height: auto;
}

.aphorism-stroke {
  stroke-dasharray: 2600;
  stroke-dashoffset: 2600;
  transition: stroke-dashoffset 1800ms ease-out;
}

.stage-reflection.in-view .aphorism-stroke {
  stroke-dashoffset: 0;
}

.aphorism-text {
  margin-top: 1rem;
  font-family: var(--font-body);
  font-style: italic;
  font-size: clamp(16px, 1.3vw, 20px);
  letter-spacing: 0.04em;
  color: var(--drafting-indigo);
  opacity: 0;
  transition: opacity 1200ms ease 600ms;
  text-align: center;
}

.stage-reflection.in-view .aphorism-text {
  opacity: 1;
}

/* ============================== DEMO STAGE ============================== */
.stage-demo {
  padding-top: 6vh;
  padding-bottom: 6vh;
}

.demo-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 4vw;
  align-items: center;
  width: 100%;
  height: 100%;
  position: relative;
  z-index: 2;
}

.demo-text {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
  max-width: 56ch;
}

.demo-stage {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 60vh;
}

.demo-frame {
  position: relative;
  width: min(56vh, 56vw);
  aspect-ratio: 1 / 1;
  background:
    radial-gradient(circle at 50% 50%, rgba(245, 239, 217, 1) 60%, rgba(224, 214, 194, 0.7) 100%);
  border: 1px solid rgba(31, 44, 92, 0.2);
  border-radius: 4px;
  box-shadow: var(--shadow-paper-soft);
  cursor: ew-resize;
  touch-action: pan-y;
  overflow: hidden;
  user-select: none;
}

.demo-crane {
  width: 100%;
  height: 100%;
  display: block;
}

#demo-crane-group {
  transition: transform 80ms linear;
}

.demo-hint {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--drafting-indigo);
  opacity: 0.7;
}

.mono-inline {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--wax-brick);
  font-variant-numeric: tabular-nums;
}

.demo-readout { color: var(--drafting-indigo); }

/* ============================== COLOPHON ============================== */
.stage-colophon {
  padding-top: 8vh;
  padding-bottom: 6vh;
}

.colophon-grid {
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 2.4rem;
  width: 100%;
  height: 100%;
  position: relative;
  z-index: 2;
}

.colophon-block {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  max-width: 60ch;
}

.colophon-grid-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 4vw;
  align-content: center;
}

.colophon-list {
  display: grid;
  grid-template-columns: minmax(140px, max-content) 1fr;
  column-gap: 1.2rem;
  row-gap: 0.5rem;
  margin: 0;
  font-family: var(--font-ui);
  font-size: 14px;
  color: var(--indigo-ink);
}

.colophon-list dt {
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 12px;
  color: var(--drafting-indigo);
  padding-top: 4px;
}

.colophon-list dd {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--indigo-ink);
}

.swatch {
  display: inline-block;
  width: 14px;
  height: 14px;
  border-radius: 3px;
  border: 1px solid rgba(31, 44, 92, 0.18);
  box-shadow: var(--shadow-paper-soft);
}

.colophon-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1.6rem;
  border-top: 1px solid rgba(31, 44, 92, 0.18);
  gap: 1rem;
  flex-wrap: wrap;
}

.colophon-note {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--drafting-indigo);
  margin: 0;
}

.begin-again {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.85rem 1.4rem;
  background: var(--indigo-ink);
  color: var(--paper-warm);
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border: none;
  border-radius: 28px;
  cursor: pointer;
  transition: transform 250ms ease, background 250ms ease;
  box-shadow: var(--shadow-paper-soft);
}

.begin-again:hover {
  transform: translateY(-2px);
  background: var(--drafting-indigo);
}

.begin-again-mark {
  font-size: 18px;
  transition: transform 300ms ease;
}

.begin-again:hover .begin-again-mark {
  transform: translateY(-3px);
}

/* ============================== STAGE RAIL ============================== */
.stage-rail {
  position: fixed;
  right: max(1vw, 14px);
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
  z-index: 50;
  padding: 0.8rem 0.6rem;
  background: rgba(245, 239, 217, 0.6);
  border: 1px solid rgba(31, 44, 92, 0.12);
  border-radius: 22px;
  backdrop-filter: blur(2px);
}

.rail-dot {
  position: relative;
  display: block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: transparent;
  border: 1px solid var(--drafting-indigo);
  text-decoration: none;
  transition: background 220ms ease, transform 220ms ease;
}

.rail-dot.rail-dot-min {
  width: 6px;
  height: 6px;
  margin-left: 2px;
  border-color: rgba(58, 79, 140, 0.5);
}

.rail-dot.active {
  background: var(--indigo-ink);
  border-color: var(--indigo-ink);
  transform: scale(1.15);
}

.rail-label {
  position: absolute;
  right: calc(100% + 12px);
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--indigo-ink);
  background: var(--paper-warm);
  padding: 0.2rem 0.55rem;
  border-radius: 12px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 200ms ease;
  border: 1px solid rgba(31, 44, 92, 0.16);
}

.rail-dot:hover .rail-label,
.rail-dot.active .rail-label {
  opacity: 1;
}

/* ============================== RESPONSIVE ============================== */
@media (max-width: 980px) {
  :root { --pad-x: 6vw; }

  .step-grid {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
    gap: 1.2rem;
  }

  .step-visual {
    min-height: 40vh;
    order: 2;
  }

  .step-numeral-wrap { order: 1; flex-direction: row; align-items: center; gap: 1rem; }
  .step-numeral { font-size: clamp(96px, 26vw, 200px); }
  .step-text { order: 3; }

  .demo-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .colophon-grid-inner { grid-template-columns: 1fr; }

  .stage-rail { display: none; }

  .cover-headline { font-size: clamp(54px, 16vw, 120px); }
}

@media (max-width: 540px) {
  :root { --pad-x: 5vw; }

  .meta-tag { font-size: 11px; padding: 0.28rem 0.7rem; }

  .step-numeral-wrap { flex-direction: column; align-items: flex-start; }
  .step-numeral { font-size: 32vw; }

  .photo-desk { width: 60vw; height: 36vw; }
}