:root {
  --bg-1: #081f3f;
  --bg-2: #114b5f;
  --panel: rgba(11, 25, 52, 0.84);
  --card: rgba(255, 255, 255, 0.08);
  --line: rgba(255, 255, 255, 0.22);
  --ink: #f8fbff;
  --ink-muted: #cfe0ff;
  --accent: #ffca3a;
  --accent-2: #23f0c7;
  --good: #35e58f;
  --bad: #ff6b6b;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: 'Avenir Next', 'Segoe UI', 'Helvetica Neue', sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 10%, rgba(255, 202, 58, 0.2), transparent 30%),
    radial-gradient(circle at 85% 80%, rgba(35, 240, 199, 0.2), transparent 30%),
    linear-gradient(140deg, var(--bg-1), var(--bg-2));
  overflow-x: hidden;
}

body::before,
body::after {
  content: '';
  position: fixed;
  inset: auto;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.15);
  pointer-events: none;
}

body::before {
  top: -80px;
  right: -80px;
}

body::after {
  bottom: -120px;
  left: -120px;
}

.layout {
  max-width: 1300px;
  margin: 0 auto;
  padding: 20px;
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 18px;
}

.sidebar,
.main {
  background: var(--panel);
  backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.sidebar {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.main {
  padding: 16px;
  display: grid;
  grid-template-rows: auto auto 1fr;
  gap: 14px;
}

h1,
h2,
h3,
h4,
p {
  margin: 0;
}

h1 {
  font-size: 1.4rem;
  letter-spacing: 0.3px;
}

h2 {
  font-size: 1.15rem;
}

p,
small,
li {
  color: var(--ink-muted);
}

.strip {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
}

.xp-wrap {
  display: grid;
  gap: 8px;
}

.bar {
  height: 12px;
  width: 100%;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.1);
  overflow: hidden;
}

.fill {
  height: 100%;
  width: 0;
  transition: width 300ms ease;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.hud-row {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  font-size: 0.88rem;
}

.mastery {
  display: grid;
  gap: 8px;
}

.mastery-row {
  display: grid;
  gap: 4px;
}

.mastery-row span {
  font-size: 0.82rem;
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.badge {
  padding: 6px 10px;
  border: 1px solid rgba(255, 202, 58, 0.6);
  border-radius: 999px;
  font-size: 0.76rem;
  color: var(--accent);
  background: rgba(255, 202, 58, 0.09);
}

.badge.ghost {
  color: var(--ink-muted);
  border-color: var(--line);
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.btn,
button {
  cursor: pointer;
  color: var(--ink);
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.08);
  border-radius: 10px;
  padding: 8px 12px;
  font-weight: 600;
  transition: transform 130ms ease, background 130ms ease;
}

.btn:hover,
button:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.14);
}

.btn:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.btn.secondary {
  border-color: rgba(35, 240, 199, 0.5);
}

.stage-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 10px;
}

.stage-card {
  text-align: left;
  min-height: 132px;
  display: grid;
  gap: 10px;
}

.stage-card.locked {
  opacity: 0.58;
}

.stage-card.complete {
  border-color: rgba(53, 229, 143, 0.8);
  box-shadow: inset 0 0 0 1px rgba(53, 229, 143, 0.5);
}

.stage-top {
  display: flex;
  justify-content: space-between;
  gap: 8px;
}

.stage-name {
  font-size: 1rem;
}

.pill {
  font-size: 0.72rem;
  color: var(--accent-2);
}

.status {
  font-size: 0.78rem;
}

.feedback {
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.07);
  padding: 10px;
  font-weight: 700;
}

.feedback.good {
  border-color: rgba(53, 229, 143, 0.7);
  color: #ddffe9;
}

.feedback.bad {
  border-color: rgba(255, 107, 107, 0.7);
  color: #ffe9e9;
}

.panel {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px;
  display: grid;
  gap: 12px;
  background: rgba(255, 255, 255, 0.06);
}

.card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
  display: grid;
  gap: 6px;
  background: rgba(255, 255, 255, 0.05);
}

.match-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.tokens,
.slots {
  display: grid;
  gap: 8px;
}

.token {
  min-height: 44px;
}

.token.selected {
  border-color: var(--accent);
}

.token.used {
  opacity: 0.45;
}

.slot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 50px;
}

.slot.correct {
  border-color: rgba(53, 229, 143, 0.7);
  box-shadow: inset 0 0 0 1px rgba(53, 229, 143, 0.6);
}

.tape {
  display: grid;
  grid-template-columns: repeat(6, minmax(40px, 1fr));
  gap: 8px;
}

.cell {
  min-height: 48px;
  border-radius: 8px;
}

.cell.selected {
  border-color: var(--accent);
  background: rgba(255, 202, 58, 0.2);
}

.cell.grouped {
  border-color: rgba(53, 229, 143, 0.6);
  background: rgba(53, 229, 143, 0.2);
}

.row-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.question-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
  display: grid;
  gap: 10px;
  background: rgba(255, 255, 255, 0.05);
}

.choice-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 8px;
}

.choice {
  min-height: 44px;
}

.hint-box,
.hint {
  color: #ffebad;
  font-size: 0.88rem;
}

.timer {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--accent);
}

.analytics {
  max-height: 190px;
  overflow: auto;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(0, 0, 0, 0.3);
  padding: 8px;
  font-size: 0.76rem;
}

.input {
  height: 40px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.1);
  color: var(--ink);
  padding: 0 10px;
}

dialog {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #0d1f43;
  color: var(--ink);
  max-width: 540px;
}

dialog::backdrop {
  background: rgba(0, 0, 0, 0.55);
}

.burst {
  position: fixed;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 10px;
  pointer-events: none;
}

.burst span {
  position: absolute;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  animation: pop 900ms ease forwards;
  transform: rotate(calc(var(--i) * 26deg)) translateX(0);
}

@keyframes pop {
  from {
    opacity: 1;
    transform: rotate(calc(var(--i) * 26deg)) translateX(0);
  }
  to {
    opacity: 0;
    transform: rotate(calc(var(--i) * 26deg)) translateX(90px);
  }
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
  }

  .match-wrap {
    grid-template-columns: 1fr;
  }

  .tape {
    grid-template-columns: repeat(4, minmax(40px, 1fr));
  }
}