:root {
  --bg: #f7f4ec;
  --ink: #12242f;
  --brand: #0d8f8b;
  --accent: #ef6c3b;
  --muted: #5f6b73;
  --card: #fffdf8;
  --ok: #2f9e44;
  --warn: #d9480f;
  --radius: 16px;
  --shadow: 0 10px 30px rgba(18, 36, 47, 0.08);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Avenir Next", "Segoe UI", sans-serif;
  background:
    radial-gradient(circle at 12% 8%, rgba(13, 143, 139, 0.18), transparent 40%),
    radial-gradient(circle at 90% 30%, rgba(239, 108, 59, 0.16), transparent 42%),
    var(--bg);
  color: var(--ink);
}

.topbar {
  padding: 1rem 1rem 0.5rem;
}

.brand-lockup {
  display: block;
  margin-bottom: 0.2rem;
}

.brand-lockup-mark {
  width: min(100%, 360px);
  height: auto;
  display: block;
  margin-bottom: 0.2rem;
}

.topbar h1 {
  margin: 0;
  letter-spacing: 0.02em;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.subtitle {
  margin: 0.2rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.shell {
  padding: 0.75rem;
  max-width: 1024px;
  margin: 0 auto;
}

.card, .panel {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 0.85rem;
}

.setup {
  display: grid;
  gap: 0.6rem;
}

label {
  font-size: 0.84rem;
  color: var(--muted);
}

input, select, button {
  font: inherit;
}

input, select {
  width: 100%;
  padding: 0.65rem;
  border-radius: 10px;
  border: 1px solid #d6ddd8;
  background: #fff;
}

button {
  border: 0;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  padding: 0.6rem 0.9rem;
  font-weight: 650;
}

button.ghost {
  background: #e8f4f3;
  color: var(--brand);
}

button.danger {
  background: #fcede8;
  color: var(--warn);
}

button:disabled {
  opacity: 0.5;
}

small {
  color: #355c61;
  min-height: 1em;
}

a {
  color: #0b6f77;
}

.hidden { display: none; }

.dashboard-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.chip {
  font-size: 0.8rem;
  background: #e8f4f3;
  color: var(--brand);
  border-radius: 999px;
  padding: 0.25rem 0.6rem;
}

.progress-row {
  margin: 0.4rem 0 1rem;
}

.bar {
  width: 100%;
  height: 10px;
  border-radius: 999px;
  background: #dde9e8;
}

.bar-fill {
  height: 100%;
  width: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--brand), #6ec8bc);
  transition: width 0.25s ease;
}

.grid {
  display: grid;
  gap: 0.75rem;
}
.admin-grid {
  grid-template-columns: 1fr;
}

.panel h3, .panel h4 {
  margin-top: 0;
}

.account-danger {
  margin-top: 1rem;
  padding-top: 0.8rem;
  border-top: 1px solid #e5d7d2;
}

.auth-reset h3 {
  margin-bottom: 0.35rem;
}

#accountEmail {
  margin: 0 0 0.7rem;
  color: var(--muted);
}

#lessonList {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
}

#lessonList button {
  width: 100%;
  text-align: left;
  border-radius: 10px;
  background: #f1f5f5;
  color: var(--ink);
  font-weight: 600;
}

#lessonList button.active {
  background: var(--brand);
  color: #fff;
}

#illustrationWrap svg {
  width: 100%;
  height: auto;
  border-radius: 10px;
  border: 1px solid #d8e2df;
  background: #fbfefe;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.8rem;
}

.video-block {
  margin-top: 0.6rem;
}

#videoLinks {
  margin: 0.5rem 0;
  padding-left: 1.1rem;
}

.video-stage {
  min-height: 110px;
  border-radius: 12px;
  border: 1px solid #d8e2df;
  background: linear-gradient(160deg, #e8f4f3, #fffdf7);
  padding: 0.7rem;
}

.video-frame {
  animation: pulseIn 0.35s ease;
}

@keyframes pulseIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.quiz-item {
  border: 1px solid #d8e2df;
  border-radius: 12px;
  padding: 0.6rem;
  margin-bottom: 0.55rem;
}

.opts {
  display: grid;
  gap: 0.35rem;
}

.opt-btn {
  border-radius: 8px;
  background: #f0f6f5;
  color: var(--ink);
  text-align: left;
  padding: 0.45rem;
}

.opt-btn.correct {
  background: #e7f8eb;
  color: var(--ok);
}

.opt-btn.wrong {
  background: #fcede8;
  color: var(--warn);
}

@media (max-width: 480px) {
  .brand-lockup-mark {
    width: min(100%, 290px);
  }
}

@media (min-width: 900px) {
  .grid {
    grid-template-columns: 0.9fr 1.5fr;
  }

  .admin-grid {
    grid-template-columns: 1fr 1fr;
  }

  #lessonPanel {
    grid-row: span 2;
  }
}