/* ─────────────────────────────────────────────────────────────────────────
   Scroll-driven iPhone — shared component (2026-09-09)
   Markup:
     <section class="ph-track" data-ph-track>
       <div class="ph-sticky">
         <div class="ph-head"> …headline (+ .ph-lede paragraph) … </div>
         <div class="ph-copy"> <ol class="ph-caps"><li class="ph-cap" data-ph-cap>…</li>…</ol> …CTA… </div>
         <div class="ph-stage">
           <div class="ph-device" aria-hidden="true">
             <span class="ph-btn ph-btn-action"></span><span class="ph-btn ph-btn-up"></span>
             <span class="ph-btn ph-btn-down"></span><span class="ph-btn ph-btn-power"></span>
             <div class="ph-screen"><div class="ph-strip"><img class="ph-shot" …>×N</div></div>
           </div>
           <ol class="ph-dots"><li class="ph-dot" data-ph-dot></li>×N</ol>
         </div>
       </div>
     </section>
   The page scroll drives the strip: the section is (N-1) × --ph-step taller than the
   sticky viewport; phone.js maps progress → screen index. No inline styles needed.
   Per-site tokens: --ph-w (device width), --ph-body (titanium gradient), --ph-step,
   --ph-top, and the caption/dot colors below.
   ───────────────────────────────────────────────────────────────────────── */

.ph-track {
  --ph-n: 1;
  --ph-step: 70vh;                 /* scroll distance per screen change */
  --ph-w: 300px;                   /* device width incl. body */
  --ph-body: linear-gradient(155deg, #b9bbc0 0%, #6c6e73 20%, #3f4044 48%, #75777c 78%, #b3b5ba 100%);
  --ph-cap: currentColor;
  --ph-cap-dim: color-mix(in oklab, currentColor 45%, transparent);
  --ph-dot: currentColor;
  position: relative;
  height: calc(100vh + (var(--ph-n) - 1) * var(--ph-step));
  height: calc(100svh + (var(--ph-n) - 1) * var(--ph-step));
}
.ph-track.ph-static { height: auto; }

.ph-sticky {
  position: sticky;
  top: 0;
  height: 100vh;
  height: 100svh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-rows: auto auto;
  align-content: center;
  column-gap: 64px;
  row-gap: 24px;
  box-sizing: border-box;
  overflow: hidden;
}
.ph-head  { grid-area: 1 / 1 / 2 / 2; align-self: end; }
.ph-copy  { grid-area: 2 / 1 / 3 / 2; align-self: start; }
.ph-stage { grid-area: 1 / 2 / 3 / 3; align-self: center; }
.ph-track.ph-static .ph-sticky { position: static; height: auto; }

.ph-stage {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

/* ── the device ─────────────────────────────────────────────────────── */
.ph-device {
  --w: var(--ph-w);
  position: relative;
  width: var(--w);
  aspect-ratio: 71.5 / 149.6;
  padding: calc(var(--w) * 0.03);
  box-sizing: border-box;
  border-radius: calc(var(--w) * 0.17);
  background: var(--ph-body);
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.35),
    inset 0 0 0 calc(var(--w) * 0.011) rgba(10, 10, 12, 0.85),
    /* Contact shadow, deliberately contained: a wider blur with a large negative
       spread paints a near-uniform haze across the whole stage column that the
       sticky box then cuts off with a hard vertical edge. */
    0 calc(var(--w) * 0.06) calc(var(--w) * 0.12) calc(var(--w) * -0.05) rgba(0, 0, 0, 0.45),
    0 calc(var(--w) * 0.02) calc(var(--w) * 0.04) calc(var(--w) * -0.02) rgba(0, 0, 0, 0.30);
}
.ph-screen {
  position: relative;
  width: 100%;
  height: 100%;
  border-radius: calc(var(--w) * 0.142);
  overflow: hidden;
  background: #000;
  transform: translateZ(0);           /* keeps the rounded clip on Safari during transforms */
}
/* Dynamic Island */
.ph-screen::before {
  content: "";
  position: absolute;
  z-index: 3;
  top: calc(var(--w) * 0.032);
  left: 50%;
  width: calc(var(--w) * 0.30);
  height: calc(var(--w) * 0.088);
  transform: translateX(-50%);
  border-radius: 999px;
  background: #000;
}
/* glass edge */
.ph-screen::after {
  content: "";
  position: absolute;
  z-index: 3;
  inset: 0;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.07);
  pointer-events: none;
}
.ph-strip {
  position: absolute;
  inset: 0;
  will-change: transform;
  /* Discrete steps (see phone.js): glide between screens, never hold a
     scroll-scrubbed fractional position — that was the visible seam. */
  transition: transform 0.34s cubic-bezier(0.22, 0.61, 0.36, 1);
}
.ph-shot {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
  user-select: none;
  -webkit-user-drag: none;
}

/* side buttons (proportions of the 16 Pro body) */
.ph-btn {
  position: absolute;
  width: calc(var(--w) * 0.012);
  background: linear-gradient(90deg, #4a4b4f, #9c9ea3 55%, #6b6d72);
  border-radius: 2px;
}
.ph-btn-action, .ph-btn-up, .ph-btn-down { left: calc(var(--w) * -0.011); border-radius: 2px 0 0 2px; }
.ph-btn-power { right: calc(var(--w) * -0.011); border-radius: 0 2px 2px 0; background: linear-gradient(270deg, #4a4b4f, #9c9ea3 55%, #6b6d72); }
.ph-btn-action { top: 18.5%; height: 4.2%; }
.ph-btn-up     { top: 25.5%; height: 7%; }
.ph-btn-down   { top: 34%;   height: 7%; }
.ph-btn-power  { top: 28%;   height: 11.5%; }

/* ── captions + dots ────────────────────────────────────────────────── */
.ph-caps { list-style: none; margin: 0; padding: 0; display: grid; }
.ph-cap {
  grid-area: 1 / 1;                 /* stacked; the active one is visible */
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.35s ease, transform 0.35s ease;
  color: var(--ph-cap);
  pointer-events: none;
}
.ph-cap.is-active { opacity: 1; transform: none; pointer-events: auto; }
.ph-track.ph-static .ph-cap { position: static; opacity: 1; transform: none; grid-area: auto; }

.ph-dots { list-style: none; margin: 0; padding: 0; display: flex; gap: 8px; }
.ph-dot {
  width: 6px; height: 6px; border-radius: 999px;
  background: var(--ph-dot); opacity: 0.25;
  transition: opacity 0.3s ease, transform 0.3s ease;
}
.ph-dot.is-active { opacity: 1; transform: scale(1.35); }
.ph-track.ph-static .ph-dots { display: none; }

/* ── phone-width layout: phone on top, copy below, both inside the sticky box ── */
@media (max-width: 860px) {
  .ph-sticky {
    grid-template-columns: 1fr;
    grid-template-rows: auto minmax(0, 1fr) auto;
    align-content: stretch;
    row-gap: 14px;
    padding: 14px 20px 18px;
  }
  .ph-head  { grid-area: 1 / 1 / 2 / 2; align-self: start; }
  .ph-stage { grid-area: 2 / 1 / 3 / 2; align-self: center; }
  .ph-copy  { grid-area: 3 / 1 / 4 / 2; align-self: end; }
  .ph-lede  { display: none; }
  /* the phone takes what the viewport leaves after ~300px of headline + caption + CTA */
  .ph-track { --ph-w: clamp(170px, calc((100svh - 310px) * 0.478), 280px); --ph-step: 55vh; }
  .ph-stage { gap: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  .ph-cap, .ph-dot, .ph-strip { transition: none; }
}