/* =====================================================================
   ROUND 4 · motion spec
   ===================================================================== */

/* ------------------------------------------------------------ 2. one daylight for the whole page
   light.js writes the paper, desk and sun values from page progress. Every
   ground reads them, so the whole page lives in one continuous light: warm
   morning at the top, a muted evening at the bottom. */
html, body { background: var(--desk); transition: none; }
.ch--white { background: var(--white); }
.ch--greige { background: var(--greige); }
.ch--ink { background: var(--ink-bg); }
.daylight {
  position: fixed; inset: 0; z-index: 45; pointer-events: none; mix-blend-mode: soft-light; opacity: var(--glow, 0.5);
  background:
    radial-gradient(60vmax 46vmax at var(--sunx, 15%) var(--suny, 10%), var(--sun, rgb(255 200 120)) 0%, transparent 70%),
    linear-gradient(to bottom, var(--sky-top, transparent), var(--sky-bottom, transparent));
}
/* the paper-toned washes follow the same light */
.hero__wash { background:
  linear-gradient(90deg, color-mix(in srgb, var(--white) 94%, transparent) 0%, color-mix(in srgb, var(--white) 86%, transparent) 36%, color-mix(in srgb, var(--white) 20%, transparent) 62%, transparent 78%),
  linear-gradient(to top, color-mix(in srgb, var(--white) 90%, transparent) 0%, transparent 22%); }
.stick { background: color-mix(in srgb, var(--white) 94%, transparent); }
@media (max-width: 860px) {
  .hero__wash { background: linear-gradient(to bottom, color-mix(in srgb, var(--white) 95%, transparent) 0%, color-mix(in srgb, var(--white) 90%, transparent) 50%, color-mix(in srgb, var(--white) 35%, transparent) 72%, color-mix(in srgb, var(--white) 10%, transparent) 100%); }
}

/* ------------------------------------------------------------ 1. hero: words out of blur, a slow breathing background */
.hero__h .wd { overflow: visible; padding: 0; margin: 0; }
.hero__h .wd__i { opacity: 0; filter: blur(8px); transform: translateY(24px);
  transition: opacity 900ms cubic-bezier(0.22, 1, 0.36, 1), filter 900ms cubic-bezier(0.22, 1, 0.36, 1), transform 900ms cubic-bezier(0.22, 1, 0.36, 1);
  transition-delay: calc(var(--i, 0) * 40ms); }
.hero__h.is-in .wd__i { opacity: 1; filter: blur(0); transform: none; }
.hero__bg img { animation: heroFade 1400ms ease-out both, bgBreath 20s ease-in-out 1400ms infinite alternate; }
@keyframes heroFade { from { opacity: 0; } to { opacity: 1; } }
@keyframes bgBreath { from { scale: 1; } to { scale: 1.06; } }

/* ------------------------------------------------------------ 3. the program sticks; 01 → 07 */
.prog { position: relative; height: calc(7 * 58svh + 100svh); margin-top: 8px; }
.prog__stage { position: sticky; top: 0; height: 100svh; display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: clamp(24px, 4vw, 64px); align-items: center; }
.prog__side { display: grid; gap: 10px; align-content: center; }
.prog__num { font-family: var(--sc-font-mono); font-weight: 500; font-size: clamp(6rem, 3rem + 10vw, 13rem); line-height: 0.82; letter-spacing: -0.08em; color: var(--acc); font-variant-numeric: tabular-nums; }
.prog__week { display: grid; grid-template-columns: repeat(7, 1fr); gap: 5px; max-width: 280px; margin-top: 14px; }
.prog__week i { display: block; height: 4px; border-radius: 2px; background: rgb(28 25 22 / 0.13); position: relative; overflow: hidden; }
.prog__week i::after { content: ""; position: absolute; inset: 0; background: var(--acc); transform: scaleX(0); transform-origin: 0 50%; transition: transform 500ms cubic-bezier(0.22, 1, 0.36, 1); }
.prog__week span.is-on i::after { transform: none; }
.prog__of { font-family: var(--sc-font-mono); font-size: 0.74rem; letter-spacing: 0.06em; color: var(--soft); text-transform: uppercase; }
.prog .lessons { position: relative; display: block; height: min(78svh, 640px); margin: 0; padding: 0; }
.prog .lesson { position: absolute; inset: 0; padding: 0; border: 0; display: grid; align-content: center; gap: 0;
  opacity: 0; transform: translateY(18px); visibility: hidden;
  transition: opacity 420ms cubic-bezier(0.22, 1, 0.36, 1), transform 420ms cubic-bezier(0.22, 1, 0.36, 1), visibility 0s 420ms; }
.prog .lesson.is-active { opacity: 1; transform: none; visibility: visible; transition-delay: 60ms, 60ms, 0s; }
.prog .lesson:last-child { display: grid; grid-template-columns: none; }
.prog .lesson__img { margin-bottom: 20px; max-height: 44svh; aspect-ratio: 16 / 9; }
.prog .lesson h4 { font-size: clamp(1.4rem, 1.1rem + 1.2vw, 2.2rem); }
.prog .lesson p { max-width: 58ch; }

/* ------------------------------------------------------------ 4. counting numbers: monospace */
.cnt { font-family: var(--sc-font-mono); font-variant-numeric: tabular-nums; letter-spacing: -0.04em; }
.proof__n .cnt { font-weight: 400; }
.buy__price { font-family: var(--sc-font-mono); font-weight: 500; letter-spacing: -0.05em; }

/* ------------------------------------------------------------ 5. buttons: magnetic, accent rises from below */
.btn { position: relative; overflow: hidden; isolation: isolate; background: #1C1916; border-color: #1C1916; color: #F7F2EC;
  transform: translate3d(var(--bx, 0px), var(--by, 0px), 0) scale(var(--press, 1));
  transition: transform 240ms cubic-bezier(0.22, 1, 0.36, 1), color 300ms, border-color 300ms; }
.btn::before { content: ""; position: absolute; inset: 0; z-index: -1; background: var(--acc);
  transform: scaleY(0); transform-origin: 50% 100%; transition: transform 300ms cubic-bezier(0.22, 1, 0.36, 1); }
.btn:hover, .btn:focus-visible { background: #1C1916; border-color: var(--acc-edge); }
.btn:hover::before, .btn:focus-visible::before { transform: scaleY(1); }
.btn:active { --press: 0.97; }
.ch--ink .btn { background: #EFEAE3; color: #1C1916; border-color: #EFEAE3; }
.ch--ink .btn .tag { border-left-color: rgb(28 25 22 / 0.3); }
.ch--ink .btn:hover, .ch--ink .btn:focus-visible { background: #EFEAE3; color: #F7F2EC; border-color: #B0525C; }
.ch--ink .btn:hover .tag { border-left-color: rgb(247 242 236 / 0.34); }
.buy .btn { background: #1C1916; color: #F7F2EC; border-color: #1C1916; }
.buy .btn .tag { border-left-color: rgb(247 242 236 / 0.34); }

/* ------------------------------------------------------------ 6. a hairline grows at the top of each chapter */
.ch:not(.hero):not(.facts)::before { content: ""; position: absolute; left: var(--gut); right: var(--gut); top: clamp(26px, 3.4vw, 52px); height: 1px; z-index: 1;
  background: var(--line-strong); transform: scaleX(0); transform-origin: 0 50%; transition: transform 1400ms cubic-bezier(0.22, 1, 0.36, 1); }
@media (min-width: 1300px) { .ch:not(.hero):not(.facts)::before { left: calc((100% - 1240px) / 2 + var(--gut)); right: calc((100% - 1240px) / 2 + var(--gut)); } }
.ch.is-seen::before { transform: scaleX(1) !important; }

@media (prefers-reduced-motion: reduce) {
  .hero__h .wd__i { opacity: 1; filter: none; transform: none; transition: none; }
  .hero__bg img { animation: none; }
  .prog { height: auto; }
  .prog__stage { position: static; height: auto; display: block; }
  .prog__side { display: none; }
  .prog .lessons { height: auto; display: grid; gap: 40px; }
  .prog .lesson { position: static; opacity: 1; transform: none; visibility: visible; }
  .btn, .btn::before { transition: none; }
  .ch::before { transform: none !important; transition: none; }
}

@media (max-width: 860px) {
  .prog { height: calc(7 * 62svh + 100svh); }
  .prog__stage { grid-template-columns: 1fr; align-content: start; gap: 8px; padding-top: 10svh; }
  .prog__side { grid-template-columns: auto 1fr; align-items: end; gap: 4px 14px; }
  .prog__side .label { display: none; }
  .prog__num { font-size: 5rem; grid-row: span 2; }
  .prog__week { margin: 0; max-width: none; }
  .prog .lessons { height: 64svh; }
  .prog .lesson { align-content: start; }
  .prog .lesson__img { max-height: 24svh; margin-bottom: 12px; }
  .prog .lesson h4 { font-size: 1.3rem; }
  .prog .lesson p { font-size: 0.95rem; line-height: 1.55; }
}

.btn:active { transform: translate3d(var(--bx, 0px), var(--by, 0px), 0) scale(0.97); }