:root {
  --bg: #020617;
  --accent: #00a3e0;
  --text: #f9fafb;
  --muted: #9ca3af;
  --card-radius: 20px;
  --ok: #34d399;
  --warn: #fbbf24;
  --err: #f87171;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: radial-gradient(circle at top, #1f2937 0, #020617 55%);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: stretch;
}

.shell {
  width: 100%;
  max-width: 1100px;
  padding: 24px 16px 32px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  position: relative;
}

.gm-badge {
  position: fixed;
  top: 12px;
  right: 16px;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.25);
  background: rgba(15,23,42,0.9);
  font-weight: 700;
  letter-spacing: 0.16em;
  font-size: 0.8rem;
  z-index: 10;
}

header {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.brand { text-align: center; display: flex; flex-direction: column; gap: 4px; }
.brand-title {
  font-weight: 700; letter-spacing: 0.18em; font-size: 0.85rem;
  text-transform: uppercase; color: var(--accent);
}
.brand-subtitle { font-size: 0.95rem; color: var(--muted); }

main { flex: 1; display: flex; flex-direction: column; gap: 20px; }

.hero-wrapper { flex: 1; display: flex; justify-content: center; align-items: center; }

.hero {
  background: linear-gradient(145deg, rgba(15,23,42,0.98), rgba(8,15,29,0.98));
  border-radius: 24px; padding: 28px 24px 26px;
  display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  gap: 24px; box-shadow: 0 24px 70px rgba(0,0,0,0.75);
  max-width: 860px; width: 100%;
}
.hero-kicker { font-size: 0.9rem; text-transform: uppercase; letter-spacing: 0.2em; color: var(--muted); }
.hero-title { font-size: clamp(2rem, 3.2vw, 2.5rem); line-height: 1.15; font-weight: 750; margin-top: 4px; }
.hero-title span { color: var(--accent); }
.hero-body { font-size: 0.95rem; color: var(--muted); max-width: 32rem; margin-top: 10px; }
.hero-actions { margin-top: 18px; display: flex; gap: 10px; flex-wrap: wrap; }

.btn {
  border: none; cursor: pointer; font-family: inherit; font-size: 0.95rem;
  border-radius: 999px; padding: 10px 22px;
  display: inline-flex; align-items: center; gap: 8px;
  transition: 0.12s ease; white-space: nowrap;
  text-decoration: none;
  color: inherit;
}
.btn-primary {
  background: var(--accent); color: #00111c;
  box-shadow: 0 16px 35px rgba(0,163,224,0.5); font-weight: 600;
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 20px 45px rgba(0,163,224,0.6);
  background: #00b4ff;
}
.btn-primary:disabled {
  opacity: 0.55;
  cursor: wait;
  transform: none;
  box-shadow: none;
}

.hero-visual { display: flex; justify-content: center; align-items: center; }
.hero-visual-inner {
  width: 200px; height: 200px; border-radius: 32px;
  background:
    radial-gradient(circle at 20% 0, rgba(56,189,248,0.4), transparent 55%),
    radial-gradient(circle at 80% 100%, rgba(34,197,94,0.3), transparent 55%),
    #020617;
  border: 1px solid rgba(148,163,184,0.35);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  text-align: center; padding: 12px; font-size: 0.85rem; color: #e5e7eb;
  box-shadow: 0 0 70px rgba(59,130,246,0.7);
}
.hero-visual-inner span { font-size: 1.6rem; font-weight: 700; letter-spacing: 0.18em; margin-bottom: 8px; }

.practice-card {
  background: rgba(15,23,42,0.99); border-radius: var(--card-radius);
  border: 1px solid rgba(148,163,184,0.35);
  box-shadow: 0 18px 60px rgba(0,0,0,0.8);
  padding: 16px 16px 14px;
}
.practice-title { font-size: 1rem; font-weight: 600; margin-bottom: 6px; }
.practice-subtitle { font-size: 0.8rem; color: var(--muted); margin-bottom: 8px; }

#viewer {
  width: 100%; height: 420px; border-radius: 18px;
  background: radial-gradient(circle at top, #111827, #020617);
  overflow: hidden; box-shadow: 0 20px 60px rgba(0,0,0,0.85);
  position: relative;
  isolation: isolate;
  transform: translateZ(0);
}

#viewer-label {
  position: absolute; top: 8px; left: 10px;
  padding: 4px 9px; border-radius: 999px; font-size: 0.78rem;
  background: rgba(15,23,42,0.9); color: #9ca3af;
  text-transform: uppercase; letter-spacing: 0.14em; z-index: 2;
}

#anim-info {
  position: absolute; bottom: 8px; left: 10px; right: 10px;
  padding: 6px 10px; border-radius: 10px; font-size: 0.72rem;
  background: rgba(15,23,42,0.85); border: 1px solid rgba(148,163,184,0.35);
  color: #cbd5e1; z-index: 2; display: block;
}
#anim-info.ok { border-color: rgba(52,211,153,0.5); color: #a7f3d0; }
#anim-info.warn { border-color: rgba(251,191,36,0.5); color: #fde68a; }
#anim-info.err { border-color: rgba(248,113,113,0.5); color: #fecaca; }

model-viewer {
  display: block;
  width: 100%;
  height: 100%;
  --poster-color: transparent;
  background: transparent;
  transform: translateZ(0);
}

.letter-display { margin-top: 10px; display: flex; align-items: center; justify-content: center; }
.letter-main { font-size: 2.8rem; font-weight: 750; line-height: 1; }

.alphabet-grid { margin-top: 10px; display: flex; flex-wrap: wrap; gap: 6px; }
.letter-pill {
  min-width: 30px; height: 30px; border-radius: 999px;
  border: 1px solid rgba(148,163,184,0.4);
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 0.8rem; color: var(--muted);
  background: rgba(15,23,42,0.8); cursor: pointer; transition: 0.12s ease;
}
.letter-pill:hover { background: rgba(59,130,246,0.25); transform: translateY(-1px); }
.letter-pill.active { background: var(--accent); color: #00111c; border-color: transparent; font-weight: 600; }
.letter-pill.neutral-pill {
  min-width: 64px;
  padding-inline: 10px;
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}

.controls-row { display: flex; gap: 8px; margin-top: 8px; flex-wrap: wrap; }
.btn-ghost {
  background: transparent; color: var(--muted);
  border: 1px solid rgba(148,163,184,0.5); padding-inline: 16px;
}
.btn-ghost:hover { background: rgba(15,23,42,0.9); color: var(--text); transform: translateY(-1px); }

.nav-links {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
}

footer { margin-top: 8px; font-size: 0.7rem; color: var(--muted); text-align: center; opacity: 0.8; }

.glossary-card {
  background: rgba(15,23,42,0.99);
  border-radius: var(--card-radius);
  border: 1px solid rgba(148,163,184,0.35);
  box-shadow: 0 18px 60px rgba(0,0,0,0.8);
  padding: 28px 24px;
  max-width: 860px;
  width: 100%;
  margin: 0 auto;
}
.glossary-card h1 {
  font-size: 1.6rem;
  margin-bottom: 8px;
}
.glossary-card h2 {
  font-size: 1.1rem;
  color: var(--accent);
  margin: 28px 0 10px;
}
.glossary-card h3 {
  font-size: 0.98rem;
  margin: 18px 0 8px;
}
.glossary-card p,
.glossary-card li {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.55;
}
.glossary-card ul { padding-left: 1.2rem; margin-bottom: 10px; }
.glossary-card code {
  font-size: 0.85em;
  color: #e2e8f0;
  background: rgba(30, 41, 59, 0.9);
  padding: 1px 6px;
  border-radius: 6px;
}
.glossary-card table {
  width: 100%;
  border-collapse: collapse;
  margin: 10px 0 16px;
  font-size: 0.85rem;
}
.glossary-card th,
.glossary-card td {
  border: 1px solid rgba(148,163,184,0.25);
  padding: 8px 10px;
  text-align: left;
  vertical-align: top;
}
.glossary-card th {
  background: rgba(30, 41, 59, 0.85);
  color: var(--text);
}
.glossary-card td { color: var(--muted); }
.glossary-card pre {
  background: rgba(2, 6, 23, 0.85);
  border: 1px solid rgba(148,163,184,0.25);
  border-radius: 12px;
  padding: 12px 14px;
  overflow-x: auto;
  font-size: 0.8rem;
  color: #e2e8f0;
  margin: 10px 0 16px;
}

@media (max-width: 720px) {
  .hero { grid-template-columns: 1fr; }
  #viewer { height: 320px; }
}

/* ============ Deletreo de frases ============ */
.phrase-input-row { display: flex; gap: 8px; margin-top: 4px; flex-wrap: wrap; }
.phrase-input {
  flex: 1;
  min-width: 200px;
  padding: 10px 16px;
  border-radius: 999px;
  border: 1px solid rgba(148,163,184,0.5);
  background: rgba(15,23,42,0.85);
  color: var(--text);
  font-family: inherit;
  font-size: 0.95rem;
}
.phrase-input::placeholder { color: rgba(156,163,175,0.7); }
.phrase-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0,163,224,0.28);
}

.phrase-chip-list { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }
.phrase-chip {
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid rgba(148,163,184,0.4);
  background: rgba(15,23,42,0.8);
  color: var(--muted);
  font-family: inherit;
  font-size: 0.8rem;
  cursor: pointer;
  transition: 0.12s ease;
}
.phrase-chip:hover { background: rgba(0,163,224,0.22); color: var(--text); transform: translateY(-1px); }

.phrase-playback {
  display: none;
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 16px;
  background: rgba(15,23,42,0.92);
  border: 1px solid rgba(148,163,184,0.35);
  flex-direction: column;
  gap: 12px;
}
.phrase-playback.is-active { display: flex; }

.phrase-playback-word { display: flex; flex-wrap: wrap; gap: 6px; }
.phrase-letter {
  min-width: 30px;
  height: 30px;
  padding: 0 4px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 700;
  background: rgba(148,163,184,0.15);
  color: var(--muted);
  border: 1px solid rgba(148,163,184,0.3);
  transition: 0.15s ease;
}
.phrase-letter.current {
  background: var(--accent);
  color: #00111c;
  border-color: transparent;
  transform: scale(1.14);
  box-shadow: 0 0 0 3px rgba(0,163,224,0.35);
}
.phrase-letter.done { background: rgba(52,211,153,0.18); color: #a7f3d0; border-color: rgba(52,211,153,0.4); }
.phrase-letter.space { background: transparent; border-style: dashed; color: var(--muted); min-width: 16px; }

.phrase-playback-controls { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.phrase-speed-label {
  font-size: 0.78rem;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}
.phrase-speed-label select {
  background: rgba(15,23,42,0.85);
  color: var(--text);
  border: 1px solid rgba(148,163,184,0.4);
  border-radius: 8px;
  padding: 4px 8px;
  font-size: 0.78rem;
  font-family: inherit;
}