:root {
  --paper: #FBF3E4;
  --ink: #2B3A55;
  --muted: #8C8878;
  --soft: #6F6A5E;
  --faint: #A8A294;
  --line: #F1ECE1;
  --white: #fff;
  --shadow: 0 3px 0 rgba(43, 58, 85, .12);
  --font: Outfit, system-ui, sans-serif;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; overflow: hidden; }
body { background: var(--paper); color: var(--ink); font-family: var(--font); -webkit-font-smoothing: antialiased; }
button { font: inherit; color: inherit; border: 0; background: none; cursor: pointer; padding: 0; }
button:focus-visible, input:focus-visible, textarea:focus-visible { outline: 2.5px solid var(--ink); outline-offset: 2px; }

/* ---------- canvas ---------- */
#stage { position: fixed; inset: 0; overflow: hidden; touch-action: none; user-select: none; -webkit-user-select: none; }
#board { position: absolute; left: 0; top: 0; transform-origin: 0 0; transition: transform .28s cubic-bezier(.2, 1, .35, 1); }
#edges { position: absolute; inset: 0; width: 100%; height: 100%; overflow: visible; pointer-events: none; }
#blobs, #menu, #ghosts { position: absolute; inset: 0; }
#blobs, #ghosts { pointer-events: none; }
#blobs .blob, #ghosts .ghost { pointer-events: auto; }
#menu { pointer-events: none; }
#menu .puck { pointer-events: auto; }

.blob {
  position: absolute; display: flex; align-items: center; justify-content: center; text-align: center;
  padding: 8px; font: 600 15px/1.15 var(--font); cursor: grab; touch-action: none;
  transition: box-shadow .16s ease, opacity .2s ease;
  will-change: transform;
}
.blob.dragging { cursor: grabbing; box-shadow: 0 10px 22px rgba(43, 58, 85, .25); z-index: 3; }
.blob.selected { box-shadow: 0 0 0 5px rgba(43, 58, 85, .25); }
/* hold ring: fills around the blob in its own colour; when it closes, the link menu opens */
@property --p { syntax: "<number>"; inherits: false; initial-value: 0; }
.blob::before {
  content: ""; position: absolute; inset: -10px; border-radius: inherit; padding: 5px; pointer-events: none;
  background: conic-gradient(var(--c, #2B3A55) calc(var(--p) * 360deg), transparent 0);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor; mask-composite: exclude; opacity: 0;
}
.blob.holding::before { opacity: 1; animation: ringfill .5s linear forwards; }
@keyframes ringfill { from { --p: 0 } to { --p: 1 } }
.blob.extra { outline: 2px dashed #B9B1A2; outline-offset: -6px; }

/* reveal: ghosts of the core terms a student has not found */
.ghost {
  position: absolute; left: 0; top: 0; display: flex; align-items: center; justify-content: center; text-align: center;
  padding: 8px; font: 600 13px/1.15 var(--font); color: var(--soft); cursor: grab; touch-action: none;
  background: color-mix(in srgb, var(--c) 14%, transparent); border: 2.5px dashed color-mix(in srgb, var(--c) 70%, transparent);
  animation: enter .45s cubic-bezier(.2, 1.4, .4, 1);
}
.ghost:hover { background: color-mix(in srgb, var(--c) 26%, transparent); }

/* link feedback: a response, not a grade */
#edges line.edge-wobble { transform-box: fill-box; transform-origin: center; animation: edgeWobble .7s ease-out; }
@keyframes edgeWobble { 0% { transform: rotate(0) } 20% { transform: rotate(4deg) } 45% { transform: rotate(-3deg) } 70% { transform: rotate(1.5deg) } 100% { transform: rotate(0) } }
#edges line.edge-ok { animation: edgeOk .5s ease-out; }
@keyframes edgeOk { from { stroke-width: 16px; } }
.blob { -webkit-touch-callout: none; }
.blob.target { box-shadow: 0 0 0 9px rgba(43, 58, 85, .10); }
.blob.target:hover { box-shadow: 0 0 0 9px rgba(43, 58, 85, .22); }
.blob.wiggle { animation: wiggle .4s ease-out; }
.blob.pulse { animation: pulse 1.1s ease-out; }
.blob.enter { animation: enter .45s cubic-bezier(.2, 1.4, .4, 1); }
.blob.faded { opacity: .28; }

@keyframes wiggle { 0% { rotate: 0deg } 35% { rotate: -3deg } 70% { rotate: 1.5deg } 100% { rotate: 0deg } }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 rgba(43, 58, 85, .35) } 100% { box-shadow: 0 0 0 22px rgba(43, 58, 85, 0) } }
@keyframes enter { from { scale: .2; opacity: 0 } to { scale: 1; opacity: 1 } }

/* connect menu pucks */
.puck {
  position: absolute; height: 34px; border-radius: 17px; background: var(--white);
  display: flex; align-items: center; gap: 9px; padding: 0 14px; white-space: nowrap;
  font: 600 13.5px var(--font); color: var(--ink); cursor: pointer;
  box-shadow: 0 2px 0 rgba(43, 58, 85, .15); z-index: 5;
  animation: pop .3s cubic-bezier(.2, 1.5, .4, 1) backwards;
}
.puck .dot { width: 10px; height: 10px; }
@keyframes pop { from { transform: scale(.3); opacity: 0 } to { transform: scale(1); opacity: 1 } }

.dot { flex: none; display: inline-block; width: 10px; height: 10px; border-radius: 50%; }

/* ---------- chrome ---------- */
.wordmark {
  position: fixed; top: 26px; left: 24px; z-index: 6;
  font: 700 18px var(--font); letter-spacing: -.01em; color: var(--ink); pointer-events: none;
}

.topbar {
  position: fixed; top: 18px; left: 50%; transform: translateX(-50%); z-index: 7;
  display: flex; gap: 10px; align-items: center; width: min(360px, calc(100vw - 32px));
}
.search {
  position: relative; flex: 1; height: 44px; border-radius: 22px; background: var(--white);
  display: flex; align-items: center; gap: 10px; padding: 0 18px; box-shadow: var(--shadow); color: var(--ink);
}
.search input { flex: 1; min-width: 0; border: 0; outline: 0; background: none; font: 500 15px var(--font); color: var(--ink); }
.search input::placeholder { color: var(--muted); }
.search:focus-within { box-shadow: var(--shadow), 0 0 0 2.5px var(--ink); }

#results {
  position: absolute; top: 52px; left: 0; right: 0; background: var(--white); border-radius: 16px;
  box-shadow: 0 6px 22px rgba(43, 58, 85, .14); padding: 6px; display: none; max-height: 60vh; overflow: auto;
}
#results.open { display: block; }
.result {
  display: flex; align-items: center; gap: 10px; width: 100%; padding: 9px 12px; border-radius: 10px;
  font: 600 14px var(--font); text-align: left;
}
.result .where { margin-left: auto; font: 500 12px var(--font); color: var(--faint); }
.result:hover, .result.active { background: var(--line); }
.result-empty { padding: 10px 12px; font: 500 13px var(--font); color: var(--muted); }

.round-btn {
  flex: none; width: 44px; height: 44px; border-radius: 50%; background: var(--white); box-shadow: var(--shadow);
  display: flex; align-items: center; justify-content: center; color: var(--ink);
}
.round-btn:hover, .pill-btn:hover, .map-chip:hover { transform: translateY(-1px); }

.pill-btn {
  height: 32px; border-radius: 16px; background: var(--white); box-shadow: 0 2px 0 rgba(43, 58, 85, .12);
  padding: 0 15px; font: 600 12.5px var(--font); color: var(--muted);
}
.pill-btn.primary { background: var(--ink); color: var(--white); }

.back-btn {
  position: fixed; top: 58px; left: 18px; z-index: 7; height: 34px; max-width: 240px; border-radius: 17px;
  background: var(--white); box-shadow: 0 2px 0 rgba(43, 58, 85, .12); display: flex; align-items: center; gap: 7px;
  padding: 0 14px 0 10px; font: 600 13px var(--font); color: var(--ink);
}
.back-btn span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.back-btn:hover { transform: translateY(-1px); }
.back-btn[hidden] { display: none; }
.under-bar {
  position: fixed; top: 68px; left: 50%; transform: translateX(-50%); z-index: 6; width: min(420px, calc(100vw - 32px));
  display: flex; flex-direction: column; align-items: center; gap: 8px; pointer-events: none;
}
#progress { font: 500 12.5px var(--font); color: var(--faint); }
.note {
  pointer-events: auto; background: var(--ink); color: var(--white); border-radius: 14px; padding: 9px 14px;
  font: 500 13.5px/1.4 var(--font); text-align: center; box-shadow: 0 6px 18px rgba(43, 58, 85, .18); animation: rise .2s ease-out;
}
.note[hidden] { display: none; }
.note-act { margin-left: 6px; font: 600 13px var(--font); color: var(--ink); background: var(--white); border-radius: 11px; padding: 3px 10px; }
.search.wobble { animation: boxWobble .45s ease-out; }
@keyframes boxWobble { 20% { transform: translateX(-6px) } 45% { transform: translateX(5px) } 70% { transform: translateX(-2px) } }
body.key-mode .student-only { display: none; }
/* test mode: every hint feature carries .hint-feature and is switched off here; add more rules for later */
body.test-mode .hint-feature { display: none; }
.test-badge { margin-left: 10px; padding: 3px 10px; border-radius: 11px; background: var(--ink); color: var(--white); font: 600 11.5px var(--font); letter-spacing: 0; vertical-align: 2px; }
.test-badge[hidden] { display: none; }
#summaryBtn[aria-pressed="true"] { background: var(--ink); color: var(--white); }
.summary {
  pointer-events: auto; background: var(--white); color: var(--ink); border-radius: 16px; padding: 12px 16px;
  font: 500 14px/1.55 var(--font); box-shadow: var(--shadow); animation: rise .2s ease-out;
}
.summary[hidden] { display: none; }
.sum-term { font-weight: 600; text-decoration: underline dotted; text-underline-offset: 3px; cursor: pointer; }
.sum-term:hover { background: var(--line); border-radius: 4px; }
.sum-term.done { color: var(--faint); cursor: default; }
.pill-btn[aria-pressed="true"] { background: var(--ink); color: var(--white); }
.tier { flex: none; height: 22px; border-radius: 11px; padding: 0 9px; font: 600 11px var(--font); background: var(--ink); color: var(--white); }
.tier.valid { background: var(--line); color: var(--soft); }
.mode-toggle { display: flex; background: var(--line); border-radius: 15px; padding: 3px; gap: 2px; }
.mode-toggle button { height: 24px; border-radius: 12px; padding: 0 11px; font: 600 11.5px var(--font); color: var(--soft); letter-spacing: 0; }
.mode-toggle button[aria-pressed="true"] { background: var(--white); color: var(--ink); box-shadow: 0 1px 0 rgba(43, 58, 85, .12); }

.corner-left { position: fixed; left: 18px; bottom: 18px; z-index: 6; display: flex; align-items: center; gap: 12px; }
.hint { font: 500 12px var(--font); color: var(--faint); }

/* ---------- map switcher ---------- */
.switcher { position: fixed; right: 18px; bottom: 18px; z-index: 8; display: flex; flex-direction: column; align-items: flex-end; gap: 10px; }
.map-chip {
  height: 40px; border-radius: 20px; background: var(--white); box-shadow: var(--shadow);
  display: flex; align-items: center; gap: 9px; padding: 0 6px 0 16px; font: 600 14px var(--font); color: var(--ink);
}
.map-chip .chev {
  width: 28px; height: 28px; border-radius: 50%; background: var(--line);
  display: flex; align-items: center; justify-content: center; transition: rotate .2s ease;
}
.map-chip[aria-expanded="true"] .chev { rotate: 45deg; }

.map-grid {
  width: min(420px, calc(100vw - 36px)); background: var(--white); border-radius: 18px; padding: 16px;
  box-shadow: 0 8px 28px rgba(43, 58, 85, .16); animation: rise .22s cubic-bezier(.2, 1.1, .35, 1);
  max-height: calc(100vh - 120px); overflow: auto;
}
@keyframes rise { from { transform: translateY(10px); opacity: 0 } to { transform: none; opacity: 1 } }
.map-grid-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; font: 600 11px var(--font); letter-spacing: .08em; color: var(--faint); }
.map-cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.map-card {
  text-align: left; border-radius: 14px; background: var(--paper); padding: 14px; min-height: 92px;
  display: flex; flex-direction: column; gap: 6px; border: 2px solid transparent;
}
.map-card:hover { border-color: rgba(43, 58, 85, .15); }
.map-card.active { border-color: var(--ink); }
.map-card .dots { display: flex; gap: 4px; margin-bottom: 4px; }
.map-card .dots .dot { width: 14px; height: 14px; }
.map-card .t { font: 600 14.5px var(--font); color: var(--ink); }
.map-card .n { font: 500 12px var(--font); color: var(--faint); }
.map-card.new { align-items: center; justify-content: center; color: var(--muted); font: 600 13px var(--font); border: 2px dashed #E7DFCF; background: none; }
.map-card.new input { width: 100%; border: 0; border-bottom: 2px solid var(--ink); background: none; font: 600 14px var(--font); color: var(--ink); outline: 0; padding: 4px 0; }

.x { font: 500 15px var(--font); color: var(--muted); width: 26px; height: 26px; border-radius: 50%; }
.x:hover { background: var(--line); }

/* ---------- detail panel ---------- */
#panel {
  position: fixed; top: 0; right: 0; bottom: 0; width: 340px; z-index: 9; background: var(--white);
  box-shadow: -4px 0 0 rgba(43, 58, 85, .07); padding: 22px 22px 90px; overflow-y: auto;
  display: flex; flex-direction: column; gap: 14px;
  transform: translateX(24px); opacity: 0; pointer-events: none;
  transition: opacity .18s ease, transform .24s cubic-bezier(.2, 1.1, .35, 1);
}
#panel.open { transform: none; opacity: 1; pointer-events: auto; }
body.panel-open .switcher { right: 358px; }

.back { align-self: flex-start; font: 600 12.5px var(--font); color: var(--muted); }
.back:hover { color: var(--ink); }
.p-head { display: flex; align-items: flex-start; gap: 12px; }
.p-swatch { flex: none; width: 36px; height: 36px; }
.p-title { flex: 1; min-width: 0; font: 600 21px/1.15 var(--font); color: var(--ink); padding-top: 5px; }
.p-from { font: 500 12.5px var(--font); color: var(--faint); margin-top: -8px; }
.p-def { font: 500 15px/1.55 var(--font); color: var(--soft); text-wrap: pretty; margin: 0; }
.term {
  font-weight: 600; color: var(--ink); cursor: pointer;
  text-decoration: underline; text-decoration-thickness: 1.5px; text-underline-offset: 3px; text-decoration-color: var(--ink);
}
.term.off { text-decoration-style: dotted; text-decoration-color: var(--faint); }
.term:hover { background: var(--line); border-radius: 3px; }
.p-label { font: 600 11px var(--font); letter-spacing: .08em; color: var(--faint); border-top: 1.5px solid var(--line); padding-top: 12px; }
.chips { display: flex; flex-wrap: wrap; gap: 7px; }
.chip { height: 28px; border-radius: 14px; background: var(--line); padding: 0 12px; font: 600 12.5px var(--font); color: var(--ink); }
.chip:hover { background: var(--ink); color: var(--white); }
.chip.here { background: none; box-shadow: inset 0 0 0 1.5px var(--line); color: var(--faint); cursor: default; }

.conns { display: flex; flex-direction: column; gap: 10px; }
.conn { display: flex; align-items: center; gap: 10px; }
.conn .swatch { flex: none; width: 24px; border-radius: 4px; }
.conn .txt { flex: 1; min-width: 0; }
.conn .lbl { font: 600 13px var(--font); color: var(--ink); }
.conn .oth { font: 500 12.5px var(--font); color: var(--faint); }
.conn .oth button { color: inherit; font: inherit; }
.conn .oth button:hover { color: var(--ink); text-decoration: underline; }
.conn .rm { opacity: 0; }
.conn:hover .rm, .conn .rm:focus-visible { opacity: 1; }
.p-empty { font: 500 13px var(--font); color: var(--faint); }
.p-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }
.p-actions .pill-btn { box-shadow: inset 0 0 0 1.5px var(--line); }

/* ---------- add term ---------- */
.add-layer { position: fixed; inset: 0; z-index: 20; background: rgba(251, 243, 228, .72); backdrop-filter: blur(2px); display: flex; align-items: center; justify-content: center; padding: 16px; }
.add-layer[hidden], .map-grid[hidden] { display: none; }
.add-card { width: min(460px, 100%); background: var(--white); border-radius: 20px; padding: 20px; box-shadow: 0 10px 34px rgba(43, 58, 85, .18); animation: rise .22s cubic-bezier(.2, 1.1, .35, 1); }
.add-head { display: flex; justify-content: space-between; align-items: center; font: 600 11px var(--font); letter-spacing: .08em; color: var(--faint); }
.add-body { display: flex; gap: 18px; align-items: flex-start; margin: 14px 0 18px; }
.add-preview {
  flex: none; width: 96px; height: 96px; display: flex; align-items: center; justify-content: center; text-align: center;
  padding: 8px; font: 600 14px/1.15 var(--font); border-radius: 56% 44% 47% 53%/48% 42% 58% 52%; transition: background .2s ease; overflow: hidden;
}
.add-fields { flex: 1; min-width: 0; display: flex; flex-direction: column; gap: 10px; }
.add-fields input, .add-fields textarea {
  width: 100%; border: 0; border-radius: 12px; background: var(--paper); padding: 10px 12px; font: 500 14px/1.45 var(--font); color: var(--ink); resize: vertical;
}
.add-fields input { font-weight: 600; font-size: 15px; }
.add-fields textarea::placeholder, .add-fields input::placeholder { color: var(--muted); }
.swatches { display: flex; gap: 10px; padding: 4px 2px; }
.swatch-btn { width: 24px; height: 24px; border-radius: 50%; }
.swatch-btn[aria-pressed="true"] { box-shadow: 0 0 0 2.5px #fff, 0 0 0 5px var(--c); }
.add-actions { display: flex; justify-content: flex-end; gap: 8px; }
.add-actions .pill-btn:not(.primary) { box-shadow: inset 0 0 0 1.5px var(--line); }

/* ---------- small screens ---------- */
@media (max-width: 720px) {
  .back-btn { top: auto; bottom: 18px; left: 92px; max-width: calc(100vw - 260px); }
  .wordmark, .hint { display: none; }
  .corner-left { flex-wrap: wrap; max-width: calc(100vw - 200px); gap: 8px; }
  .topbar { top: 14px; }
  #panel { top: auto; left: 0; width: auto; height: 62vh; border-radius: 20px 20px 0 0; box-shadow: 0 -4px 0 rgba(43, 58, 85, .07); transform: translateY(24px); padding-bottom: 28px; }
  body.panel-open .switcher { display: none; }
  .add-body { flex-direction: column; align-items: center; }
  .add-fields { width: 100%; }
}