/* =====================================================================
   BreakThrough Education — Lesson V4 "Vonk" (js/lesson-v4.js)
   The premium study experience: a cinematic dark cover, then a warm
   editorial paper canvas. A week is a JOURNEY of stations (Lees, Vrae,
   Taal, Woorde, Skryf, Mondeling, Oefeninge, Verslag); each station is
   one or more focused "moments" (one activity per screen).
   Root: #lv4Ov  ·  namespace: v4-  ·  body class: lesson-open
   Every screen sets --v4a (station accent). Global .oef-* is restyled
   ONLY scoped under #lv4Ov. Mobile-first (360px+).
   ===================================================================== */

body.lesson-open { overflow: hidden; }

#lv4Ov:focus { outline: none; }   /* open() moves focus to the dialog root */
#lv4Ov {
  position: fixed; inset: 0; z-index: 4000;
  height: 100vh; height: 100dvh;
  background: #f7f5f0;
  color: #1b2032;
  font-family: var(--font, "Baloo 2", "Segoe UI", system-ui, sans-serif);
  --v4a: #1b2032;
  --v4-ink: #1b2032;
  --v4-mut: #667085;
  --v4-line: #eae6db;
  --v4-card: #fffefb;
  --v4-serif: "Lora", "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  --v4-kick: "Quicksand", "Segoe UI", sans-serif;
  display: flex; flex-direction: column;
}

/* =================== top chrome =================== */
.v4-hd {
  flex: none; position: relative; z-index: 6;
  padding-top: env(safe-area-inset-top, 0px);
  background: rgba(247, 245, 240, .88);
  -webkit-backdrop-filter: blur(16px) saturate(1.5);
  backdrop-filter: blur(16px) saturate(1.5);
  border-bottom: 1px solid var(--v4-line);
  transition: background .5s;
}
#lv4Ov.v4-dark .v4-hd {                       /* over the dark cover the chrome goes glassy-dark */
  background: rgba(16, 19, 34, .55);
  border-bottom-color: rgba(255,255,255,.08);
}
.v4-top {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 14px 8px;
  max-width: 980px; margin: 0 auto;
}
.v4-close {
  flex: none; width: 40px; height: 40px; border-radius: 50%;
  border: 1px solid var(--v4-line); background: var(--v4-card); color: var(--v4-ink);
  font-family: inherit; font-size: 1.5rem; line-height: 1; padding: 0 0 3px;
  display: grid; place-items: center; cursor: pointer;
  transition: transform .15s cubic-bezier(.22,.61,.36,1), box-shadow .15s;
}
.v4-close:hover { transform: translateX(-2px); box-shadow: 0 4px 14px rgba(20,25,45,.1); }
#lv4Ov.v4-dark .v4-close { background: rgba(255,255,255,.08); border-color: rgba(255,255,255,.14); color: #fff; }
.v4-tmid { flex: 1; min-width: 0; text-align: center; }
.v4-ttitle {
  font-weight: 800; font-size: 1rem; letter-spacing: -.01em;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.v4-tsub {
  font-family: var(--v4-kick); font-weight: 700;
  text-transform: uppercase; letter-spacing: .14em;
  font-size: .6rem; color: var(--v4-mut); margin-top: 1px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
#lv4Ov.v4-dark .v4-ttitle { color: #fff; }
#lv4Ov.v4-dark .v4-tsub { color: rgba(255,255,255,.6); }
.v4-pts {
  flex: none; font-weight: 800; font-size: .88rem;
  background: var(--v4-card); border: 1px solid var(--v4-line); border-radius: 999px;
  padding: 7px 13px; box-shadow: 0 2px 8px rgba(20,25,45,.05);
}
#lv4Ov.v4-dark .v4-pts { background: rgba(255,255,255,.08); border-color: rgba(255,255,255,.14); color: #fff; }
.v4-pts-n { display: inline-block; min-width: 1ch; }
.v4-pts.v4-pop { animation: v4PtsPop .5s cubic-bezier(.34,1.56,.64,1); }
@keyframes v4PtsPop { 30% { transform: scale(1.18); } }

/* ---- the journey trail (stations) ---- */
.v4-trail {
  display: flex; gap: 6px; align-items: stretch;
  max-width: 980px; margin: 0 auto;
  padding: 2px 14px 10px;
  overflow-x: auto; scrollbar-width: none; -webkit-overflow-scrolling: touch;
}
.v4-trail::-webkit-scrollbar { display: none; }
.v4-st {
  flex: none; display: flex; align-items: center; gap: 6px;
  border: 1px solid var(--v4-line); background: var(--v4-card);
  border-radius: 999px; padding: 5px 12px 5px 7px;
  font-family: inherit; font-weight: 700; font-size: .74rem; color: var(--v4-mut);
  cursor: pointer; white-space: nowrap;
  transition: border-color .2s, color .2s, box-shadow .2s, transform .15s;
}
.v4-st:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(20,25,45,.08); }
.v4-st-ico {
  width: 22px; height: 22px; border-radius: 50%;
  display: grid; place-items: center; font-size: .72rem;
  background: #f0ede5; transition: background .2s;
}
.v4-st.on { border-color: var(--sta, var(--v4a)); color: var(--v4-ink); box-shadow: 0 4px 14px rgba(20,25,45,.08); }
.v4-st.on .v4-st-ico { background: var(--sta, var(--v4a)); color: #fff; }
.v4-st.done { color: var(--v4-ink); }
.v4-st.done .v4-st-ico { background: #dff5e8; }
.v4-st.done .v4-st-ico::after { content: "✓"; font-weight: 900; font-size: .7rem; color: #12996b; position: absolute; }
.v4-st.done .v4-st-emoji { visibility: hidden; }
.v4-st .v4-st-ico { position: relative; }
#lv4Ov.v4-dark .v4-st { background: rgba(255,255,255,.07); border-color: rgba(255,255,255,.12); color: rgba(255,255,255,.75); }
#lv4Ov.v4-dark .v4-st .v4-st-ico { background: rgba(255,255,255,.12); }
#lv4Ov.v4-dark .v4-st.on { border-color: rgba(255,255,255,.55); color: #fff; }

/* =================== scroll body =================== */
.v4-body {
  flex: 1; min-height: 0;
  overflow-y: auto; -webkit-overflow-scrolling: touch;
  overscroll-behavior: contain;
  scroll-behavior: smooth;
  background:
    radial-gradient(700px 340px at 85% -80px, color-mix(in srgb, var(--v4a) 7%, transparent), transparent 70%),
    #f7f5f0;
  transition: background .6s;
}
@supports not (background: color-mix(in srgb, red 5%, white)) {
  .v4-body { background: #f7f5f0; }
}
#lv4Ov.v4-dark .v4-body { background: transparent; }
#lv4Ov.v4-dark { background: #10131f; }
.v4-inner {
  position: relative;
  max-width: 760px; margin: 0 auto;
  padding: 26px 18px calc(120px + env(safe-area-inset-bottom, 0px));
}

/* entrance animation — each card staggers in */
.v4-in { animation: v4In .5s cubic-bezier(.22,.61,.36,1) both; animation-delay: var(--d, 0s); }
@keyframes v4In { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }

/* =================== shared atoms =================== */
.v4-card {
  background: var(--v4-card); border: 1px solid var(--v4-line);
  border-radius: 22px; padding: 26px 26px 24px;
  box-shadow: 0 1px 2px rgba(20,25,45,.04), 0 14px 40px -18px rgba(20,25,45,.12);
  margin-bottom: 18px; position: relative;
}
.v4-kick {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--v4-kick); font-weight: 700;
  text-transform: uppercase; letter-spacing: .15em; font-size: .64rem;
  color: var(--v4a); margin-bottom: 12px;
}
.v4-kick .v4-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--v4a); box-shadow: 0 0 0 4px color-mix(in srgb, var(--v4a) 15%, transparent); }
.v4-h2 {
  font-family: var(--v4-serif); font-weight: 700; letter-spacing: -.015em;
  font-size: 1.5rem; line-height: 1.25; margin: 0 0 10px;
}
.v4-serif { font-family: var(--v4-serif); font-size: 1.06rem; line-height: 1.78; margin: 0 0 4px; }
.v4-muted { color: var(--v4-mut); }
.v4-chip {
  display: inline-flex; align-items: center; gap: 6px;
  border-radius: 999px; padding: 4px 12px;
  font-weight: 700; font-size: .74rem;
  background: #f0ede5; color: #4b5265;
}
.v4-btn {
  border: none; border-radius: 999px; cursor: pointer;
  font-family: inherit; font-weight: 800; font-size: .95rem;
  padding: 13px 26px; color: #fff; background: var(--v4a);
  box-shadow: 0 8px 22px -8px color-mix(in srgb, var(--v4a) 70%, transparent);
  transition: transform .15s cubic-bezier(.22,.61,.36,1), box-shadow .2s, filter .2s;
}
.v4-btn:hover { filter: brightness(1.07); transform: translateY(-1px); }
.v4-btn:active { transform: translateY(1px); box-shadow: 0 4px 10px -6px color-mix(in srgb, var(--v4a) 70%, transparent); }
.v4-btn:disabled { background: #d9d4c8; color: #8a8fa0; box-shadow: none; cursor: default; transform: none; }
.v4-ghost {
  border: 1px solid var(--v4-line); background: var(--v4-card); color: var(--v4-ink);
  border-radius: 999px; padding: 10px 20px; font-family: inherit;
  font-weight: 700; font-size: .88rem; cursor: pointer;
  transition: border-color .2s, box-shadow .2s, transform .15s;
}
.v4-ghost:hover { border-color: #c9c3b4; box-shadow: 0 4px 14px rgba(20,25,45,.07); transform: translateY(-1px); }

/* narratable row (text + circular listen button) */
.v4-nrow { display: flex; gap: 10px; align-items: flex-start; margin-bottom: 8px; }
.v4-nrow .v4-nt { flex: 1; min-width: 0; }
.v4-say {
  flex: none; width: 34px; height: 34px; margin-top: 2px;
  border-radius: 50%; border: 1px solid var(--v4-line);
  background: var(--v4-card); font-size: .85rem; cursor: pointer;
  display: grid; place-items: center; color: var(--v4a);
  transition: transform .15s, box-shadow .2s, background .2s;
}
.v4-say:hover { transform: scale(1.08); box-shadow: 0 4px 12px rgba(20,25,45,.1); }
.v4-say.on { background: var(--v4a); color: #fff; border-color: var(--v4a); animation: v4Pulse 1.6s ease-in-out infinite; }
@keyframes v4Pulse { 50% { box-shadow: 0 0 0 8px color-mix(in srgb, var(--v4a) 18%, transparent); } }

/* the "why" explainer strip */
.v4-why {
  margin-top: 12px; padding: 12px 16px;
  background: #fbf7ea; border-left: 4px solid #eab308; border-radius: 0 12px 12px 0;
  font-size: .92rem; line-height: 1.6;
}

/* =================== COVER (cinematic dark) =================== */
.v4-cover { position: relative; z-index: 1; text-align: center; padding: 34px 8px 10px; color: #fff; }
.v4-cover-sky {
  position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none;
  /* fixed inside the scroller: the sky stays put while the route scrolls */
  background:
    radial-gradient(900px 500px at 15% -10%, rgba(124, 58, 237, .38), transparent 60%),
    radial-gradient(800px 520px at 95% 8%, rgba(6, 182, 212, .3), transparent 62%),
    radial-gradient(700px 500px at 50% 115%, rgba(217, 119, 6, .22), transparent 65%),
    #10131f;
}
.v4-cover-sky i {
  position: absolute; border-radius: 50%; background: #fff; opacity: .5;
  width: 3px; height: 3px;
  animation: v4Twinkle 3.4s ease-in-out infinite;
}
.v4-cover-sky i:nth-child(2) { animation-delay: .9s; }
.v4-cover-sky i:nth-child(3) { animation-delay: 1.7s; }
.v4-cover-sky i:nth-child(4) { animation-delay: 2.4s; }
.v4-cover-sky i:nth-child(5) { animation-delay: .4s; }
.v4-cover-sky i:nth-child(6) { animation-delay: 2.9s; }
@keyframes v4Twinkle { 50% { opacity: .12; transform: scale(.7); } }
.v4-wknum {
  font-family: var(--v4-serif); font-weight: 700;
  font-size: 1.05rem; letter-spacing: .32em; text-transform: uppercase;
  color: rgba(255,255,255,.55); margin-bottom: 18px;
}
.v4-hello {
  display: inline-flex; align-items: center; gap: 10px;
  background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.13);
  border-radius: 999px; padding: 6px 18px 6px 8px; margin-bottom: 24px;
  font-weight: 700; font-size: .9rem;
}
.v4-hello svg, .v4-hello img { width: 34px; height: 34px; border-radius: 50%; display: block; }
.v4-hero {
  font-family: var(--v4-serif); font-weight: 700; letter-spacing: -.02em;
  font-size: clamp(2rem, 6.5vw, 3.1rem); line-height: 1.14; margin: 0 0 18px;
  text-wrap: balance;
}
.v4-cover .v4-lede {
  font-family: var(--v4-serif); font-size: 1.08rem; line-height: 1.75;
  color: rgba(255,255,255,.82); max-width: 560px; margin: 0 auto;
}
.v4-cover .v4-nrow { max-width: 620px; margin: 0 auto 6px; text-align: left; }
.v4-cover .v4-say { background: rgba(255,255,255,.1); border-color: rgba(255,255,255,.2); color: #fff; }
.v4-cover-note {
  display: inline-flex; gap: 8px; align-items: center; margin-top: 16px;
  background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.12);
  border-radius: 12px; padding: 9px 16px; font-size: .84rem; color: rgba(255,255,255,.8);
}
/* what awaits this week — the route preview */
.v4-route { margin: 30px auto 0; max-width: 620px; text-align: left; }
.v4-route-t {
  font-family: var(--v4-kick); font-weight: 700; letter-spacing: .16em;
  text-transform: uppercase; font-size: .64rem; color: rgba(255,255,255,.55);
  margin-bottom: 10px; display: flex; justify-content: space-between; align-items: baseline;
}
.v4-route-i {
  display: flex; align-items: center; gap: 12px;
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.1);
  border-radius: 14px; padding: 10px 14px; margin-bottom: 8px;
  transition: background .2s;
}
.v4-route-i:hover { background: rgba(255,255,255,.1); }
.v4-route-ico {
  flex: none; width: 34px; height: 34px; border-radius: 10px;
  display: grid; place-items: center; font-size: 1rem;
  background: var(--sta, #444); color: #fff;
}
.v4-route-n { flex: 1; font-weight: 700; font-size: .92rem; }
.v4-route-m { font-size: .76rem; color: rgba(255,255,255,.55); font-weight: 700; }
.v4-route-i.done .v4-route-n { text-decoration: line-through; opacity: .6; }
.v4-route-i.done .v4-route-m::before { content: "✓ "; color: #4ade80; }
.v4-cover-cta { margin: 30px 0 8px; }
.v4-cover-cta .v4-btn {
  background: #fff; color: #10131f; font-size: 1.05rem; padding: 16px 40px;
  box-shadow: 0 10px 34px -8px rgba(255,255,255,.45);
}

/* goals (doelwitte) — checklist look */
.v4-goal-list { list-style: none; margin: 6px 0 0; padding: 0; counter-reset: v4goal; }
.v4-goal-list li {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 12px 0; border-bottom: 1px dashed var(--v4-line);
}
.v4-goal-list li:last-child { border-bottom: none; }
.v4-goal-list li::before {
  counter-increment: v4goal; content: counter(v4goal);
  flex: none; width: 26px; height: 26px; margin-top: 2px;
  border-radius: 50%; display: grid; place-items: center;
  background: color-mix(in srgb, var(--v4a) 12%, white); color: var(--v4a);
  font-weight: 800; font-size: .8rem;
}
.v4-goal-t { flex: 1; font-family: var(--v4-serif); font-size: 1.02rem; line-height: 1.65; }

/* =================== station intro =================== */
.v4-stintro { text-align: center; padding: 26px 10px 8px; }
.v4-stintro-ico {
  width: 72px; height: 72px; margin: 0 auto 18px;
  border-radius: 24px; display: grid; place-items: center; font-size: 2rem;
  background: var(--v4a); color: #fff;
  box-shadow: 0 16px 40px -12px color-mix(in srgb, var(--v4a) 65%, transparent);
  animation: v4Float 4.5s ease-in-out infinite;
}
@keyframes v4Float { 50% { transform: translateY(-6px); } }
.v4-stintro .v4-hero { color: var(--v4-ink); font-size: clamp(1.6rem, 5vw, 2.3rem); margin-bottom: 10px; }
.v4-stintro-what {
  font-family: var(--v4-serif); color: #444c60; font-size: 1.04rem; line-height: 1.7;
  max-width: 520px; margin: 0 auto 16px;
}
.v4-stintro-meta { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }

/* =================== LEES (reader) =================== */
.v4-readbar {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  margin-bottom: 14px;
}
.v4-fs { display: inline-flex; border: 1px solid var(--v4-line); border-radius: 999px; overflow: hidden; background: var(--v4-card); }
.v4-fs button {
  border: none; background: none; cursor: pointer; font-family: inherit;
  padding: 6px 13px; font-weight: 800; color: var(--v4-mut);
}
.v4-fs button:first-child { font-size: .74rem; border-right: 1px solid var(--v4-line); }
.v4-fs button:last-child { font-size: .95rem; }
.v4-fs button:hover { color: var(--v4-ink); background: #f5f2ea; }
.v4-reader { --v4fs: 1; }
.v4-reader .v4-serif { font-size: calc(1.08rem * var(--v4fs)); line-height: 1.85; }
.v4-reader .v4-nrow { margin-bottom: 14px; }
.v4-read-title {
  font-family: var(--v4-serif); font-weight: 700; letter-spacing: -.015em;
  font-size: calc(1.65rem * var(--v4fs)); line-height: 1.25; margin: 2px 0 6px;
}
.v4-gloss-hint {
  display: flex; gap: 8px; align-items: center;
  font-size: .8rem; color: var(--v4-mut); margin: 2px 0 16px;
}
/* teacher glossary words woven into the text (also .rt-pop so the app's
   tap-popup opens) get a warm dotted affordance */
#lv4Ov .rt-pop {
  border-bottom: 2px dotted #b3ad9c;                                     /* fallback */
  border-bottom: 2px dotted color-mix(in srgb, var(--v4a) 55%, transparent);
  cursor: pointer; border-radius: 2px;
  transition: background .15s;
}
#lv4Ov .rt-pop:hover { background: #f1eee4; background: color-mix(in srgb, var(--v4a) 10%, transparent); }
/* glossary rail at the end of the reading */
.v4-gloss-rail {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 10px; margin-top: 6px;
}
.v4-gloss-i {
  background: #faf8f2; border: 1px solid var(--v4-line); border-radius: 14px;
  padding: 12px 14px; font-size: .88rem; line-height: 1.5;
}
.v4-gloss-i b { display: block; font-size: .95rem; margin-bottom: 3px; color: var(--v4a); }
.v4-gloss-i span { color: #4b5265; }

/* =================== BEGRIP (questions) =================== */
/* how-questions-work legend */
.v4-legend { display: grid; gap: 10px; margin-top: 4px; }
.v4-legend-i {
  display: flex; gap: 12px; align-items: center;
  border: 1px solid var(--v4-line); border-radius: 14px; padding: 11px 14px;
  background: #faf8f2;
}
.v4-legend-i b { font-size: .9rem; }
.v4-legend-i p { margin: 0; font-size: .8rem; color: var(--v4-mut); }
.v4-lvl {
  flex: none; display: inline-flex; align-items: center; gap: 5px;
  border-radius: 999px; padding: 4px 12px; font-weight: 800; font-size: .72rem;
}
.v4-lvl.l1 { background: #e5f7ee; color: #0f8a5f; }
.v4-lvl.l3 { background: #fdf1de; color: #b45309; }
.v4-lvl.l5 { background: #f1eafe; color: #7c3aed; }
/* question progress dots */
.v4-qdots { display: flex; gap: 7px; justify-content: center; margin: 2px 0 16px; flex-wrap: wrap; }
.v4-qdot {
  width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--v4-line);
  background: var(--v4-card); font-family: inherit; font-weight: 800; font-size: .74rem;
  color: var(--v4-mut); cursor: pointer; display: grid; place-items: center;
  transition: transform .15s, box-shadow .2s;
}
.v4-qdot:hover { transform: scale(1.1); }
.v4-qdot.on { border-color: var(--v4a); color: var(--v4a); box-shadow: 0 0 0 4px color-mix(in srgb, var(--v4a) 14%, transparent); }
.v4-qdot.p { background: #12b76a; border-color: #12b76a; color: #fff; }
.v4-qdot.f { background: #f04438; border-color: #f04438; color: #fff; }
.v4-qdot.try { background: #fdf1de; border-color: #f3c88a; color: #b45309; }
.v4-q-top { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 14px; }
.v4-q-text { font-size: 1.18rem; line-height: 1.7; }
.v4-qpts { margin-left: auto; }
.v4-ta {
  width: 100%; min-height: 110px; resize: vertical;
  border: 1.5px solid var(--v4-line); border-radius: 16px;
  background: #fdfcf8; color: var(--v4-ink);
  font-family: var(--v4-serif); font-size: 1.02rem; line-height: 1.7;
  padding: 14px 16px; margin-top: 14px;
  transition: border-color .2s, box-shadow .2s;
}
.v4-ta:focus { outline: none; border-color: var(--v4a); box-shadow: 0 0 0 4px color-mix(in srgb, var(--v4a) 12%, transparent); }
.v4-ta.ok { border-color: #12b76a; background: #f4fcf8; }
.v4-ta.bad { border-color: #f04438; background: #fef5f4; }
.v4-q-act { display: flex; gap: 10px; align-items: center; margin-top: 14px; flex-wrap: wrap; }
.v4-fb { border-radius: 14px; padding: 13px 16px; margin-top: 14px; font-size: .95rem; line-height: 1.6; animation: v4In .35s cubic-bezier(.22,.61,.36,1); }
.v4-fb.ok { background: #e5f7ee; color: #0b6b4a; }
.v4-fb.bad { background: #fdeaea; color: #b42318; }
.v4-fb.warn { background: #fdf6e3; color: #92600a; }
.v4-memo {
  margin-top: 14px; padding: 14px 16px;
  background: #f4f7fd; border-left: 4px solid #4e7fff; border-radius: 0 14px 14px 0;
  font-size: .95rem; line-height: 1.65;
}
.v4-hint {
  display: flex; gap: 10px; align-items: center; margin-top: 12px;
  background: #fbf7ea; border: 1px dashed #e2ca7e; border-radius: 14px;
  padding: 11px 14px; font-size: .88rem;
}
.v4-hint button { margin-left: auto; flex: none; }

/* ---- slide-up text sheet (read the passage while answering) ---- */
.v4-sheet {
  position: absolute; inset: 0; z-index: 40; display: none;
  background: rgba(16,19,31,.45);
  -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px);
}
.v4-sheet.open { display: block; animation: v4FadeIn .25s; }
@keyframes v4FadeIn { from { opacity: 0; } }
.v4-sheet-panel {
  position: absolute; left: 0; right: 0; bottom: 0; top: 12%;
  background: #fdfcf8; border-radius: 26px 26px 0 0;
  box-shadow: 0 -18px 60px rgba(16,19,31,.35);
  display: flex; flex-direction: column;
  animation: v4SheetUp .38s cubic-bezier(.22,.61,.36,1);
}
@keyframes v4SheetUp { from { transform: translateY(6%); opacity: .4; } }
.v4-sheet-hd {
  flex: none; display: flex; align-items: center; gap: 10px;
  padding: 14px 20px 10px; border-bottom: 1px solid var(--v4-line);
}
.v4-sheet-hd b { flex: 1; font-family: var(--v4-serif); font-size: 1.05rem; }
.v4-sheet-x {
  flex: none; width: 34px; height: 34px; border-radius: 50%;
  border: 1px solid var(--v4-line); background: #fff; cursor: pointer;
  font-size: 1.1rem; line-height: 1; display: grid; place-items: center;
}
.v4-sheet-bd { flex: 1; overflow-y: auto; padding: 18px 22px 40px; -webkit-overflow-scrolling: touch; }
.v4-sheet-bd .v4-serif { font-size: 1rem; line-height: 1.8; margin-bottom: 14px; }
.v4-sheet-bd .v4-para-hl {
  background: #fdf6dd; border-radius: 10px; padding: 10px 12px;
  box-shadow: 0 0 0 2px #f0d98c;
}

/* =================== TAAL (concept + drills) =================== */
.v4-ex-rail { display: grid; gap: 10px; margin-top: 14px; }
.v4-ex {
  position: relative; background: #faf8f2; border: 1px solid var(--v4-line);
  border-radius: 14px; padding: 13px 16px 13px 40px;
  font-family: var(--v4-serif); font-size: .98rem; line-height: 1.6;
}
.v4-ex::before {
  content: "“"; position: absolute; left: 13px; top: 4px;
  font-family: var(--v4-serif); font-size: 1.9rem; color: var(--v4a); opacity: .55;
}
.v4-drill-q { font-size: 1.12rem; line-height: 1.7; }
.v4-try {
  margin-top: 12px; font-size: .84rem; color: var(--v4-mut);
  display: flex; gap: 8px; align-items: center;
}
.v4-selffb { border-radius: 12px; padding: 10px 14px; margin-top: 12px; font-size: .88rem; }
.v4-selffb.ok { background: #e5f7ee; color: #0b6b4a; }
.v4-selffb.try { background: #fdf6e3; color: #92600a; }
.v4-model { overflow: hidden; max-height: 0; transition: max-height .4s cubic-bezier(.22,.61,.36,1); }
.v4-model.open { max-height: 640px; }
.v4-model-in { padding-top: 4px; }

/* =================== WOORDE (flashcards + match) =================== */
.v4-deck { text-align: center; }
.v4-deck-meta {
  display: flex; justify-content: space-between; align-items: center;
  font-weight: 700; font-size: .82rem; color: var(--v4-mut); margin-bottom: 12px;
}
.v4-flash-wrap { perspective: 1200px; max-width: 460px; margin: 0 auto 16px; }
.v4-flash {
  position: relative; width: 100%; min-height: 240px; cursor: pointer;
  transform-style: preserve-3d; transition: transform .55s cubic-bezier(.4,.1,.2,1);
  border: none; background: none; padding: 0; font-family: inherit; display: block;
}
.v4-flash.flip { transform: rotateY(180deg); }
.v4-flash-f, .v4-flash-b {
  position: absolute; inset: 0; border-radius: 22px;
  -webkit-backface-visibility: hidden; backface-visibility: hidden;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 10px; padding: 26px;
}
.v4-flash-f {
  background: var(--v4a);                                                /* fallback */
  background: linear-gradient(150deg, color-mix(in srgb, var(--v4a) 88%, #000) 0%, var(--v4a) 60%, color-mix(in srgb, var(--v4a) 72%, #fff) 100%);
  color: #fff; box-shadow: 0 18px 44px -14px rgba(20,25,45,.35);
  box-shadow: 0 18px 44px -14px color-mix(in srgb, var(--v4a) 70%, transparent);
}
.v4-flash-b {
  background: var(--v4-card); border: 1px solid var(--v4-line);
  transform: rotateY(180deg);
  box-shadow: 0 14px 36px -16px rgba(20,25,45,.2);
}
.v4-flash-word { font-family: var(--v4-serif); font-weight: 700; font-size: 2rem; letter-spacing: -.01em; text-wrap: balance; }
.v4-flash-flip { font-size: .74rem; font-weight: 700; opacity: .75; letter-spacing: .08em; text-transform: uppercase; }
.v4-flash-en { font-weight: 800; font-size: 1.35rem; color: var(--v4-ink); }
.v4-flash-sin { font-family: var(--v4-serif); font-style: italic; font-size: .98rem; line-height: 1.6; color: #4b5265; }
.v4-flash .v4-say { position: absolute; top: 14px; right: 14px; z-index: 2; background: rgba(255,255,255,.16); border-color: rgba(255,255,255,.3); color: #fff; }
.v4-flash.flip .v4-say { visibility: hidden; }
.v4-deck-act { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }
.v4-deck-act .know { background: #12b76a; box-shadow: 0 8px 22px -8px rgba(18,183,106,.7); }
.v4-deck-act .again { background: #f79009; box-shadow: 0 8px 22px -8px rgba(247,144,9,.7); }
.v4-deck-done { padding: 30px 10px; }
.v4-deck-done .v4-stintro-ico { background: #12b76a; }
/* deck progress bar */
.v4-deckbar { height: 6px; border-radius: 3px; background: #ece8dd; overflow: hidden; margin-bottom: 16px; }
.v4-deckbar i { display: block; height: 100%; border-radius: 3px; background: var(--v4a); transition: width .4s cubic-bezier(.22,.61,.36,1); }

/* blitspas match game */
.v4-match { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 14px; }
.v4-mt {
  border: 1.5px solid var(--v4-line); border-radius: 14px;
  background: var(--v4-card); padding: 13px 12px;
  font-family: inherit; font-weight: 700; font-size: .9rem; color: var(--v4-ink);
  cursor: pointer; transition: border-color .15s, background .15s, transform .15s, opacity .3s;
  min-height: 52px;
}
.v4-mt:hover { transform: translateY(-1px); }
.v4-mt.sel { border-color: var(--v4a); background: color-mix(in srgb, var(--v4a) 9%, white); }
.v4-mt.hit { border-color: #12b76a; background: #e5f7ee; color: #0f8a5f; opacity: .55; pointer-events: none; }
.v4-mt.miss { animation: v4Shake .4s; border-color: #f04438; background: #fdeaea; }
@keyframes v4Shake { 20%, 60% { transform: translateX(-5px); } 40%, 80% { transform: translateX(5px); } }
.v4-match-done { text-align: center; padding: 16px 0 4px; font-weight: 800; font-size: 1.05rem; color: #0f8a5f; }

/* =================== SKRYF (studio) =================== */
.v4-checks { list-style: none; margin: 8px 0 0; padding: 0; }
.v4-checks li { border-bottom: 1px dashed var(--v4-line); }
.v4-checks li:last-child { border-bottom: none; }
.v4-checks label {
  display: flex; gap: 12px; align-items: flex-start; cursor: pointer;
  padding: 11px 2px; font-size: .95rem; line-height: 1.6;
}
.v4-checks input {
  appearance: none; -webkit-appearance: none; flex: none;
  width: 22px; height: 22px; margin-top: 2px; border-radius: 8px;
  border: 2px solid #cfc9ba; background: #fff; cursor: pointer;
  display: grid; place-items: center;
  transition: background .2s, border-color .2s;
}
.v4-checks input:checked { background: var(--v4a); border-color: var(--v4a); }
.v4-checks input:checked::after { content: "✓"; color: #fff; font-weight: 900; font-size: .8rem; }
.v4-checks input:checked + span { color: var(--v4-mut); text-decoration: line-through; }
.v4-studio-meta { display: flex; align-items: center; gap: 14px; margin: 16px 0 4px; }
.v4-ring { position: relative; width: 62px; height: 62px; flex: none; }
.v4-ring svg { transform: rotate(-90deg); }
.v4-ring .bg { stroke: #ece8dd; }
.v4-ring .fg { stroke: var(--v4a); transition: stroke-dashoffset .4s cubic-bezier(.22,.61,.36,1), stroke .3s; }
.v4-ring.met .fg { stroke: #12b76a; }
.v4-ring-n {
  position: absolute; inset: 0; display: grid; place-items: center;
  font-weight: 800; font-size: .82rem;
}
.v4-studio-target { font-size: .85rem; color: var(--v4-mut); font-weight: 700; }
.v4-studio-target .met { color: #0f8a5f; }
.v4-wta { min-height: 260px; }

/* =================== MONDELING (recorder) =================== */
.v4-rec { text-align: center; padding: 6px 0 2px; }
.v4-rec-btn {
  width: 84px; height: 84px; border-radius: 50%; border: none; cursor: pointer;
  background: #f04438; color: #fff; font-size: 1.7rem;
  box-shadow: 0 12px 34px -10px rgba(240,68,56,.65);
  transition: transform .2s, box-shadow .2s, background .2s;
  display: inline-grid; place-items: center;
}
.v4-rec-btn:hover { transform: scale(1.06); }
.v4-rec-btn.rec { animation: v4RecPulse 1.4s ease-in-out infinite; background: #b42318; }
@keyframes v4RecPulse { 50% { box-shadow: 0 0 0 16px rgba(240,68,56,.15); } }
.v4-rec-time { font-weight: 800; font-variant-numeric: tabular-nums; margin-top: 12px; font-size: 1.05rem; }
.v4-rec-note { font-size: .8rem; color: var(--v4-mut); margin-top: 10px; }
.v4-rec audio { width: 100%; margin-top: 14px; }

/* =================== OEFENINGE (BTOefening reskin) =================== */
.v4-oefhost { margin-top: 4px; }
#lv4Ov .oef { font-family: var(--font, "Baloo 2", sans-serif); }
#lv4Ov .oef-title { color: var(--v4-ink); font-weight: 800; letter-spacing: -.01em; }
#lv4Ov .oef-bubble { background: #fff; border-color: var(--v4-line); border-radius: 16px; }
#lv4Ov .oef-bubble::before { border-right-color: var(--v4-line); }
#lv4Ov .oef-bubble-t, #lv4Ov .oef-sin, #lv4Ov .oef-verdict, #lv4Ov .oef-q { color: var(--v4-ink); }
#lv4Ov .oef-word { color: var(--v4a); }
#lv4Ov .oef-line { border-color: var(--v4-line); }
#lv4Ov .oef-tile, #lv4Ov .oef-opt, #lv4Ov .oef-card {
  background: #fff; border-color: #e3ddcf; color: var(--v4-ink);
  box-shadow: 0 2px 8px rgba(20,25,45,.05);
}
#lv4Ov .oef-opt.sel, #lv4Ov .oef-card.sel { border-color: var(--v4a); background: color-mix(in srgb, var(--v4a) 8%, white); color: var(--v4-ink); }
#lv4Ov .oef-card-cap { color: var(--v4-mut); }
#lv4Ov .oef-say { border-radius: 50%; box-shadow: 0 4px 12px color-mix(in srgb, var(--v4a) 30%, transparent); }
#lv4Ov .oef-check {
  border-radius: 999px; background: var(--v4a); color: #fff;
  box-shadow: 0 8px 22px -8px color-mix(in srgb, var(--v4a) 70%, transparent);
}
#lv4Ov .oef-check:disabled { background: #e3ddcf; color: #9aa3af; box-shadow: none; }
#lv4Ov .oef-result { border-radius: 16px; }
#lv4Ov .oef-result.ok { background: #e5f7ee; }
#lv4Ov .oef-result.bad { background: #fdeaea; }
#lv4Ov .oef-why { color: var(--v4-ink); border-radius: 0 10px 10px 0; }
#lv4Ov .oef-next, #lv4Ov .oef-retry { border-radius: 999px; }
#lv4Ov .oef-oop-input { background: #fff; border-color: var(--v4-line); color: var(--v4-ink); }
#lv4Ov .oef-oop-input:focus { border-color: var(--v4a); }
#lv4Ov .oef-pas-item { background: #fff; border-color: #e3ddcf; color: var(--v4-ink); box-shadow: 0 2px 8px rgba(20,25,45,.04); }
#lv4Ov .oef-pas-item.sel { border-color: var(--v4a); background: color-mix(in srgb, var(--v4a) 8%, white); }
#lv4Ov .oef-pas-item.paired { border-color: #12b76a; background: #e5f7ee; }

/* =================== VERSLAG (week report) =================== */
.v4-report-hero { text-align: center; padding: 10px 0 4px; }
.v4-donut-wrap { display: flex; gap: 22px; align-items: center; justify-content: center; flex-wrap: wrap; margin: 8px 0 4px; }
.v4-donut { position: relative; width: 150px; height: 150px; flex: none; }
.v4-donut svg { transform: rotate(-90deg); }
.v4-donut circle { fill: none; stroke-width: 14; stroke-linecap: butt; }
.v4-donut-c {
  position: absolute; inset: 0; display: grid; place-items: center; text-align: center;
}
.v4-donut-c b { font-size: 1.7rem; font-weight: 800; display: block; line-height: 1.1; }
.v4-donut-c span { font-size: .68rem; font-weight: 700; color: var(--v4-mut); text-transform: uppercase; letter-spacing: .1em; }
.v4-rep-legend { display: grid; gap: 8px; min-width: 190px; }
.v4-rep-li {
  display: flex; align-items: center; gap: 10px;
  font-weight: 700; font-size: .88rem;
}
.v4-rep-li i { width: 12px; height: 12px; border-radius: 4px; flex: none; }
.v4-rep-li .n { margin-left: auto; font-weight: 800; }
.v4-levbars { display: grid; gap: 12px; margin-top: 6px; }
.v4-levbar-t { display: flex; justify-content: space-between; font-size: .82rem; font-weight: 700; margin-bottom: 5px; }
.v4-levbar { height: 10px; border-radius: 5px; background: #ece8dd; overflow: hidden; display: flex; }
.v4-levbar i { display: block; height: 100%; }
.v4-levbar .ok { background: #12b76a; }
.v4-levbar .bad { background: #f04438; }
.v4-again-list { display: grid; gap: 8px; margin-top: 4px; }
.v4-again-i {
  display: flex; gap: 10px; align-items: center; text-align: left;
  border: 1px solid var(--v4-line); border-radius: 14px; background: #faf8f2;
  padding: 11px 14px; font-family: inherit; font-size: .88rem; color: var(--v4-ink);
  cursor: pointer; transition: border-color .2s, transform .15s;
}
.v4-again-i:hover { border-color: #c9c3b4; transform: translateY(-1px); }
.v4-again-i .v4-lvl { margin-left: auto; flex: none; }
.v4-finish-cta { text-align: center; padding: 8px 0 20px; }
.v4-finish-cta .v4-btn { font-size: 1.05rem; padding: 16px 40px; }
.v4-finish-done {
  display: inline-flex; align-items: center; gap: 8px;
  background: #e5f7ee; color: #0f8a5f; border-radius: 999px;
  padding: 14px 34px; font-weight: 800; font-size: 1rem;
}
.v4-quiet { display: block; margin: 14px auto 0; border: none; background: none; color: var(--v4-mut); font-family: inherit; font-weight: 700; font-size: .88rem; cursor: pointer; text-decoration: underline; }
.v4-foot-note { text-align: center; font-size: .78rem; color: var(--v4-mut); margin-top: 12px; }

/* =================== ekstra-section image (teacher/AI diagram) =================== */
.v4-ekstra-prent { text-align: center; margin: 6px 0 14px; }
.v4-ximg { max-width: 100%; border-radius: 14px; border: 1px solid var(--v4-line); background: #fff; }
span.v4-ximg.emoji { font-size: 3rem; border: none; background: none; }

/* =================== bottom navigation =================== */
.v4-foot {
  position: absolute; left: 0; right: 0; bottom: 0; z-index: 8;
  padding: 10px 16px calc(12px + env(safe-area-inset-bottom, 0px));
  display: flex; align-items: center; gap: 12px;
  background: linear-gradient(to top, rgba(247,245,240,.96) 55%, rgba(247,245,240,0));
  pointer-events: none;
}
#lv4Ov.v4-dark .v4-foot { background: linear-gradient(to top, rgba(16,19,31,.95) 55%, rgba(16,19,31,0)); }
.v4-foot > * { pointer-events: auto; }
.v4-prev {
  flex: none; width: 46px; height: 46px; border-radius: 50%;
  border: 1px solid var(--v4-line); background: var(--v4-card); color: var(--v4-ink);
  font-size: 1.3rem; line-height: 1; cursor: pointer; display: grid; place-items: center;
  box-shadow: 0 4px 14px rgba(20,25,45,.08);
  transition: transform .15s, box-shadow .2s, opacity .2s;
}
.v4-prev:hover { transform: translateX(-2px); }
.v4-prev[disabled] { opacity: 0; pointer-events: none; }
#lv4Ov.v4-dark .v4-prev { background: rgba(255,255,255,.09); border-color: rgba(255,255,255,.16); color: #fff; }
.v4-mdots { flex: 1; display: flex; gap: 5px; justify-content: center; align-items: center; }
.v4-mdot { width: 7px; height: 7px; border-radius: 4px; background: #d8d2c4; transition: width .25s, background .25s; }
.v4-mdot.on { width: 22px; background: var(--v4a); }
.v4-mdot.seen { background: color-mix(in srgb, var(--v4a) 45%, #d8d2c4); }
#lv4Ov.v4-dark .v4-mdot { background: rgba(255,255,255,.25); }
#lv4Ov.v4-dark .v4-mdot.on { background: #fff; }
.v4-next {
  flex: none; border: none; border-radius: 999px; cursor: pointer;
  font-family: inherit; font-weight: 800; font-size: .95rem;
  padding: 14px 26px; color: #fff; background: var(--v4a);
  box-shadow: 0 10px 26px -8px color-mix(in srgb, var(--v4a) 75%, transparent);
  transition: transform .15s cubic-bezier(.22,.61,.36,1), filter .2s, box-shadow .2s;
  max-width: 60vw; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.v4-next:hover { filter: brightness(1.08); transform: translateY(-1px); }
.v4-next:active { transform: translateY(1px); }

/* =================== responsive =================== */
@media (max-width: 560px) {
  .v4-inner { padding: 18px 12px calc(110px + env(safe-area-inset-bottom, 0px)); }
  .v4-card { padding: 20px 18px 18px; border-radius: 18px; }
  .v4-h2 { font-size: 1.3rem; }
  .v4-hero { font-size: clamp(1.7rem, 8vw, 2.2rem); }
  .v4-match { grid-template-columns: 1fr 1fr; gap: 8px; }
  .v4-mt { font-size: .82rem; padding: 11px 8px; }
  .v4-donut { width: 128px; height: 128px; }
  .v4-st { font-size: .7rem; padding: 4px 10px 4px 6px; }
  .v4-next { padding: 13px 20px; font-size: .88rem; }
  .v4-sheet-panel { top: 8%; }
}
@media (min-width: 900px) {
  .v4-inner { max-width: 820px; }
  .v4-gloss-rail { grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); }
}

/* =================== reduced motion =================== */
@media (prefers-reduced-motion: reduce) {
  #lv4Ov *, #lv4Ov *::before, #lv4Ov *::after {
    animation-duration: .01ms !important; animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
  .v4-body { scroll-behavior: auto; }
}

/* ---- teksformaat: strooibiljet (flyer) — the reading text LOOKS like its text type ---- */
.v4-fmt-flyer { background: #fffdf4; border: 2px dashed rgba(140, 110, 40, .45); border-radius: 10px; position: relative; }
.v4-fmt-flyer .v4-read-title { text-align: center; text-transform: uppercase; letter-spacing: .04em; border-bottom: 3px double rgba(140, 110, 40, .4); padding-bottom: 10px; }
.v4-fmt-flyer .v4-serif { text-align: center; }
.v4-fmt-flyer .v4-serif b { color: #8a5a10; }
.v4-flyer-top, .v4-flyer-bot { text-align: center; color: rgba(140, 110, 40, .5); font-size: .72rem; letter-spacing: .1em; user-select: none; }
.v4-flyer-bot { margin-top: 10px; }

/* ---- numbered paragraphs (verhalende teks) — terugvoer kan na "paragraaf N" verwys ---- */
.v4-fmt-genommer { counter-reset: v4para; }
.v4-fmt-genommer .v4-nrow > p.v4-serif, .v4-fmt-genommer > p.v4-serif { counter-increment: v4para; position: relative; padding-left: 36px; }
.v4-fmt-genommer .v4-nrow > p.v4-serif::before, .v4-fmt-genommer > p.v4-serif::before { content: counter(v4para); position: absolute; left: 0; top: .35em; min-width: 20px; text-align: center; font-size: 11px; font-weight: 800; opacity: .5; border-radius: 8px; padding: 1px 5px; background: rgba(127, 127, 127, .14); }