/* v13.32.0: Weekly Vocab Booster (KS3/KS4). The Drop's look: a deliberate night-time HUD in both themes. */
.vk { --k-bg: #0B1020; --k-panel: #131A2E; --k-ink: #E8ECF8; --k-soft: #9AA3C0; --k-line: #26304D; --k-accent: #3EE6D2; --k-accent-ink: #062A27;
  --k-alt: #A78BFA; --k-ok: #4ADE80; --k-ok-soft: #12321F; --k-bad: #F87171; --k-bad-soft: #3A1414;
  --k-display: "Chakra Petch", "Rajdhani", "Segoe UI", system-ui, sans-serif; --k-mono: "IBM Plex Mono", ui-monospace, Menlo, monospace;
  background: radial-gradient(900px 380px at 75% -10%, #1B2550 0%, transparent 60%), var(--k-bg); color: var(--k-ink);
  border-radius: 14px; padding: 18px; color-scheme: dark; min-height: 60vh; }
.vk a { color: var(--k-accent); }
.vk-head h1, .vk-word, .vk-ask, .vk-score, .vk-set-top b { font-family: var(--k-display); letter-spacing: .02em; }
.vk-head h1 { font-size: 34px; margin: 4px 0 6px; text-transform: uppercase; }
.vk-head p, .vk-small, .vk-range { color: var(--k-soft); margin: 0; }
.vk-small { font-size: 13px; }
.vk-eyebrow, .vk-label { font: 600 12px/1.2 var(--k-mono); letter-spacing: .12em; text-transform: uppercase; color: var(--k-soft); }
.vk-sets { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 12px; margin-top: 16px; }
.vk-set { background: var(--k-panel); border: 1px solid var(--k-line); border-left: 3px solid var(--k-accent); border-radius: 6px; padding: 12px 14px; display: grid; gap: 8px; }
.vk-set.is-locked { border-left-color: var(--k-line); opacity: .6; }
.vk-set.is-done { border-left-color: var(--k-ok); }
.vk-set-top { display: flex; justify-content: space-between; align-items: center; gap: 8px; }
.vk-set-top b { font-size: 18px; text-transform: uppercase; }
.vk-pill { font: 600 11px/1 var(--k-mono); letter-spacing: .08em; text-transform: uppercase; padding: 5px 8px; border-radius: 2px; background: rgba(167,139,250,.18); color: var(--k-alt); }
.vk-set-bar, .vk-bar { height: 6px; background: var(--k-line); border-radius: 99px; overflow: hidden; }
.vk-set-bar i, .vk-bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--k-alt), var(--k-accent)); transition: width .4s; }
.vk-row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.vk-between { justify-content: space-between; }
.vk-centre { justify-content: center; }
.vk-btn { display: inline-block; cursor: pointer; border: 0; border-radius: 4px; padding: 9px 16px; font: 700 14px/1.2 var(--k-display); letter-spacing: .05em; text-transform: uppercase;
  background: var(--k-accent); color: var(--k-accent-ink) !important; text-decoration: none; }
.vk-btn.vk-ghost { background: transparent; color: var(--k-ink) !important; border: 1.5px solid var(--k-line); }
.vk-btn[disabled] { opacity: .4; cursor: default; }
.vk-btn:focus-visible, .vk-box:focus-visible { outline: 3px solid var(--k-accent); outline-offset: 2px; }
.vk-top { display: flex; gap: 12px; align-items: center; margin-bottom: 8px; flex-wrap: wrap; }
.vk-back { font-weight: 700; text-decoration: none; }
.vk-card { background: var(--k-panel); border: 1px solid var(--k-line); border-radius: 8px; padding: 18px; margin-top: 12px; display: grid; gap: 12px; }
.vk-word { font-size: clamp(34px, 6vw, 52px); margin: 0; color: var(--k-accent); }
.vk-meaning { font-size: 19px; margin: 0; }
.vk-eg { margin: 0; color: var(--k-soft); font-style: italic; }
.vk-cols { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.vk-chips { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 6px; }
.vk-chip { padding: 4px 10px; border-radius: 3px; background: rgba(62,230,210,.12); border: 1px solid rgba(62,230,210,.35); font-size: 14px; }
.vk-chips.is-ant .vk-chip { background: rgba(167,139,250,.12); border-color: rgba(167,139,250,.4); }
.vk-tip { margin: 0; padding: 8px 12px; border-left: 3px solid var(--k-alt); background: rgba(167,139,250,.08); }
.vk-nav { justify-content: space-between; margin-top: 12px; }
.vk-ask { font-size: 22px; margin: 0; text-wrap: balance; }
.vk-boxes { display: flex; flex-wrap: wrap; gap: 6px; }
.vk-box { width: 42px; height: 50px; border-radius: 4px; border: 2px solid var(--k-line); background: var(--k-bg); color: var(--k-ink); text-align: center;
  font: 700 24px/46px var(--k-mono); text-transform: uppercase; padding: 0; }
.vk-box.is-given { display: inline-block; border-color: transparent; background: rgba(62,230,210,.14); color: var(--k-accent); text-transform: none; }
input.vk-box { text-transform: lowercase; }
.vk-box.is-wrong { border-color: var(--k-bad); background: var(--k-bad-soft); }
.vk-fb { margin: 0; padding: 8px 12px; border-radius: 4px; }
.vk-fb.is-ok { background: var(--k-ok-soft); color: var(--k-ok); }
.vk-fb.is-no { background: var(--k-bad-soft); color: var(--k-bad); }
.vk-center { text-align: center; justify-items: center; }
.vk-score { font-size: 64px; margin: 0; color: var(--k-accent); }
.vk-score small { font-size: 24px; color: var(--k-soft); }
.vk-missed { justify-content: center; }
.vk-empty { padding: 30px 10px; text-align: center; color: var(--k-soft); }
.vk-lb { position: fixed; inset: 0; z-index: 10000; background: rgba(5,8,18,.82); display: grid; place-items: center;
  padding: max(16px, env(safe-area-inset-top, 0px)) max(16px, env(safe-area-inset-right, 0px)) max(16px, env(safe-area-inset-bottom, 0px)) max(16px, env(safe-area-inset-left, 0px)); }
.vk-lb figure { margin: 0; max-width: min(720px, 100%); max-height: 100%; overflow: auto; background: #131A2E; color: #E8ECF8; border: 1px solid #26304D; border-radius: 8px; }
.vk-lb img { display: block; width: 100%; height: auto; max-height: 62vh; object-fit: contain; background: #0B1020; }
.vk-lb figcaption { padding: 12px 16px; display: grid; gap: 4px; }
.vk-lb figcaption b { font: 600 11px/1.4 "IBM Plex Mono", ui-monospace, monospace; letter-spacing: .12em; text-transform: uppercase; color: #9AA3C0; margin-top: 4px; }
.vk-lb .vk-clue { font-size: 18px; font-weight: 700; color: #3EE6D2; }
.vk-x { position: fixed; top: calc(12px + env(safe-area-inset-top, 0px)); right: calc(12px + env(safe-area-inset-right, 0px)); width: 44px; height: 44px; border-radius: 50%;
  border: 0; background: #E8ECF8; color: #0B1020; font-size: 26px; cursor: pointer; }
@media (max-width: 560px) { .vk { padding: 12px; } .vk-cols { grid-template-columns: minmax(0, 1fr); } .vk-box { width: 34px; height: 44px; font-size: 20px; line-height: 40px; } }
@media (prefers-reduced-motion: reduce) { .vk * { transition: none !important; } }

/* the lesson: three columns, as the Year 4 and 5 lesson */
.vk-cols3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; align-items: start; }
.vk-col { margin-top: 12px; align-content: start; }
.vk-pic { padding: 0; border: 0; background: none; cursor: zoom-in; border-radius: 6px; overflow: hidden; }
.vk-pic img { display: block; width: 100%; height: auto; max-width: 100%; }
.vk-scene { margin: 0; color: var(--k-soft); }
.vk-cluetxt { margin: 0; font-weight: 700; color: var(--k-accent); font-size: 17px; }
.vk-opts { display: grid; gap: 8px; }
.vk-opt { text-align: left; cursor: pointer; padding: 10px 12px; border-radius: 4px; border: 1.5px solid var(--k-line); background: var(--k-bg); color: var(--k-ink); font: 600 16px/1.2 var(--k-display); letter-spacing: .02em; }
.vk-opt:hover:not([disabled]) { border-color: var(--k-alt); }
.vk-opt.is-right { border-color: var(--k-ok); background: var(--k-ok-soft); color: var(--k-ok); }
.vk-opt.is-wrong { border-color: var(--k-bad); background: var(--k-bad-soft); color: var(--k-bad); }
.vk-reveal { display: grid; gap: 6px; }
.vk-reveal p { margin: 0; }
.vk-word-sm { font: 700 22px/1.1 var(--k-display); color: var(--k-accent); }
.vk-pool { min-height: 34px; }
.vk-drag { cursor: grab; user-select: none; }
.vk-drag.is-sel { outline: 2px solid var(--k-accent); }
.vk-bin { border: 1.5px dashed var(--k-line); border-radius: 6px; padding: 8px 10px; min-height: 64px; cursor: pointer; }
.vk-bin.is-over, .vk-bin:focus-visible { border-color: var(--k-accent); outline: none; }
.vk-chip.is-in { background: var(--k-ok-soft); border-color: var(--k-ok); color: var(--k-ok); }
.vk-toastline { margin-bottom: 8px; }
.vk-cluelink { background: none; border: 0; padding: 0; color: var(--k-accent); text-decoration: underline; cursor: pointer; font: inherit; justify-self: start; }
@media (max-width: 900px) { .vk-cols3 { grid-template-columns: minmax(0, 1fr); } }