:root{
  --bg:#0b1020;
  --bg2:#111831;
  --panel:#141d38;
  --card:#17223f;
  --line:#2c3b66;
  --text:#eef4ff;
  --muted:#b6c3e1;
  --accent:#60a5fa;
  --accent2:#22c55e;
  --accent3:#f59e0b;
  --gear1:#58a6ff;
  --gear1dark:#2258b6;
  --gear2:#ff8a8a;
  --gear2dark:#b93a3a;
  --shadow:0 14px 40px rgba(0,0,0,.28);
  --radius:22px;
}

*{ box-sizing:border-box; }

body{
  margin:0;
  font-family: Inter, system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  color:var(--text);
  background:
    radial-gradient(circle at top left, rgba(37,99,235,.22) 0%, transparent 26%),
    radial-gradient(circle at top right, rgba(34,197,94,.16) 0%, transparent 22%),
    linear-gradient(180deg, #09111f 0%, #0b1020 100%);
  min-height:100vh;
}

.app{
  max-width:1450px;
  margin:0 auto;
  padding:18px;
}

.hero{
  background:linear-gradient(135deg, rgba(96,165,250,.18), rgba(34,197,94,.10));
  border:1px solid rgba(255,255,255,.08);
  border-radius:28px;
  padding:20px;
  box-shadow:var(--shadow);
  margin-bottom:18px;
  backdrop-filter: blur(8px);
}

.hero-top{
  display:flex;
  justify-content:space-between;
  align-items:flex-start;
  gap:16px;
  flex-wrap:wrap;
}

.brand{
  display:flex;
  gap:14px;
  align-items:flex-start;
}

.logo{
  width:58px;
  height:58px;
  border-radius:18px;
  background:
    radial-gradient(circle at 35% 35%, #93c5fd, #2563eb 65%, #1e3a8a);
  display:grid;
  place-items:center;
  box-shadow:0 12px 24px rgba(37,99,235,.35);
  flex:0 0 auto;
}

.logo::before{
  content:"⚙";
  font-size:30px;
}

h1{
  margin:0;
  font-size:clamp(1.8rem, 2.6vw, 2.8rem);
  line-height:1.08;
}

.subtitle{
  margin:8px 0 0;
  color:var(--muted);
  max-width:850px;
  line-height:1.55;
}

.hero-actions{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  align-items:center;
}

.lang-switch{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
  background:rgba(255,255,255,.04);
  border:1px solid rgba(255,255,255,.08);
  border-radius:999px;
  padding:6px;
}

.lang-btn{
  appearance:none;
  border:none;
  background:transparent;
  color:var(--text);
  padding:10px 14px;
  border-radius:999px;
  font:inherit;
  font-weight:700;
  cursor:pointer;
  transition:.2s ease;
}

.lang-btn.active{
  background:linear-gradient(135deg, #60a5fa, #2563eb);
  box-shadow:0 8px 18px rgba(37,99,235,.35);
}

.ghost-btn,.primary-btn{
  appearance:none;
  border:none;
  color:var(--text);
  padding:11px 14px;
  border-radius:14px;
  font:inherit;
  font-weight:700;
  cursor:pointer;
  transition:.2s ease;
}

.ghost-btn{
  background:rgba(255,255,255,.05);
  border:1px solid rgba(255,255,255,.08);
}

.ghost-btn:hover{
  transform:translateY(-1px);
  background:rgba(255,255,255,.08);
}

.primary-btn{
  background:linear-gradient(135deg,#22c55e,#16a34a);
  box-shadow:0 10px 24px rgba(34,197,94,.28);
}

.primary-btn:hover{
  transform:translateY(-1px);
}

.small-btn{
  padding:9px 12px;
  font-size:.92rem;
}

.grid{
  display:grid;
  grid-template-columns:360px minmax(0,1fr) 390px;
  gap:18px;
  align-items:start;
}

.panel{
  background:linear-gradient(180deg, rgba(255,255,255,.04), rgba(255,255,255,.02));
  border:1px solid rgba(255,255,255,.08);
  border-radius:24px;
  box-shadow:var(--shadow);
  overflow:hidden;
  backdrop-filter: blur(8px);
}

.panel-inner{
  padding:18px;
}

.panel-title{
  display:flex;
  align-items:center;
  gap:10px;
  margin:0 0 16px;
  font-size:1.15rem;
  font-weight:800;
}

.panel-icon{
  width:12px;
  height:12px;
  border-radius:50%;
  background:var(--accent);
  box-shadow:0 0 0 6px rgba(96,165,250,.18);
  flex:0 0 auto;
}

.results-header{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:10px;
  flex-wrap:wrap;
}

.section{
  margin-bottom:18px;
  padding:16px;
  background:rgba(255,255,255,.025);
  border:1px solid rgba(255,255,255,.06);
  border-radius:18px;
}

.section h3{
  margin:0 0 12px;
  display:flex;
  align-items:center;
  gap:10px;
  font-size:1rem;
}

.gear-dot{
  width:12px;
  height:12px;
  border-radius:50%;
  flex:0 0 auto;
}

.field{
  margin-bottom:12px;
}

.field:last-child{
  margin-bottom:0;
}

label{
  display:block;
  margin-bottom:6px;
  font-weight:700;
}

.help{
  display:block;
  margin-top:6px;
  color:var(--muted);
  font-size:.92rem;
  line-height:1.45;
}

input[type="number"], select{
  width:100%;
  border:none;
  outline:none;
  padding:12px 14px;
  border-radius:14px;
  background:#0e1730;
  color:var(--text);
  border:1px solid rgba(255,255,255,.08);
  font:inherit;
}

input[readonly]{
  background:#0c1428;
}

input[type="range"]{
  width:100%;
  accent-color:#60a5fa;
  cursor:pointer;
}

.segmented{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:8px;
}

.driver-option{
  display:flex;
  align-items:center;
  gap:10px;
  padding:12px;
  border-radius:14px;
  cursor:pointer;
  background:#0e1730;
  border:1px solid rgba(255,255,255,.08);
  transition:.2s ease;
}

.driver-option:hover{
  border-color:rgba(96,165,250,.45);
}

.driver-option input{
  accent-color:#60a5fa;
  cursor:pointer;
}

.presets{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:10px;
}

.preset-btn{
  appearance:none;
  border:none;
  border-radius:14px;
  padding:12px 10px;
  color:var(--text);
  background:#0e1730;
  border:1px solid rgba(255,255,255,.08);
  font:inherit;
  font-weight:700;
  cursor:pointer;
  transition:.2s ease;
}

.preset-btn:hover{
  transform:translateY(-1px);
  border-color:rgba(96,165,250,.45);
  background:#122040;
}

.formula-card{
  background:linear-gradient(180deg, rgba(96,165,250,.10), rgba(96,165,250,.04));
  border:1px solid rgba(96,165,250,.18);
  border-radius:18px;
  padding:14px;
  color:#dbeafe;
  line-height:1.75;
  font-size:.98rem;
}

.formula-inline{
  display:block;
  margin-top:6px;
  font-weight:700;
}

.stage-toolbar{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:10px;
  flex-wrap:wrap;
  margin-bottom:12px;
}

.badge-row{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
}

.badge{
  display:inline-flex;
  align-items:center;
  gap:8px;
  background:rgba(255,255,255,.05);
  border:1px solid rgba(255,255,255,.08);
  color:#dbeafe;
  border-radius:999px;
  padding:8px 12px;
  font-size:.92rem;
  font-weight:700;
}

.canvas-shell{
  background:
    radial-gradient(circle at center, rgba(255,255,255,.06), transparent 60%),
    linear-gradient(180deg, #0a1328, #0c1530);
  border:1px solid rgba(255,255,255,.08);
  border-radius:22px;
  overflow:hidden;
  min-height:520px;
}

#canvasHost{
  width:100%;
  min-height:520px;
}

.legend{
  display:flex;
  flex-wrap:wrap;
  gap:10px 14px;
  margin-top:14px;
}

.legend-item{
  display:flex;
  align-items:center;
  gap:8px;
  padding:8px 12px;
  background:rgba(255,255,255,.03);
  border:1px solid rgba(255,255,255,.06);
  border-radius:999px;
  color:var(--muted);
  font-size:.92rem;
}

.legend-line{
  width:24px;
  height:0;
  border-top:2px dashed #dbeafe;
  opacity:.85;
}

.legend-center{
  width:10px;
  height:10px;
  border-radius:50%;
  background:#ffffff;
  box-shadow:0 0 0 4px rgba(255,255,255,.12);
}

.metric-grid{
  display:grid;
  gap:12px;
}

.metric{
  background:linear-gradient(180deg, rgba(255,255,255,.045), rgba(255,255,255,.025));
  border:1px solid rgba(255,255,255,.08);
  border-radius:18px;
  padding:14px;
}

.metric .label{
  color:var(--muted);
  font-size:.93rem;
  margin-bottom:7px;
}

.metric .value{
  font-size:1.35rem;
  font-weight:900;
}

.step-box{
  background:linear-gradient(180deg, rgba(34,197,94,.10), rgba(34,197,94,.04));
  border:1px solid rgba(34,197,94,.18);
  border-radius:18px;
  padding:16px;
  margin-top:14px;
}

.step-box h3{
  margin:0 0 10px;
  color:#dcfce7;
  font-size:1rem;
}

.steps{
  margin:0;
  padding-left:20px;
  line-height:1.7;
  color:#eefbf3;
}

.steps li{
  margin-bottom:10px;
}

.explain-card{
  margin-top:14px;
  background:linear-gradient(180deg, rgba(245,158,11,.12), rgba(245,158,11,.04));
  border:1px solid rgba(245,158,11,.20);
  border-radius:18px;
  padding:14px;
  color:#fff7dd;
  line-height:1.65;
}

.teacher-tip{
  margin-top:14px;
  background:linear-gradient(180deg, rgba(96,165,250,.11), rgba(96,165,250,.04));
  border:1px solid rgba(96,165,250,.18);
  border-radius:18px;
  padding:14px;
  color:#dbeafe;
  line-height:1.65;
}

.footer-note{
  margin-top:14px;
  color:var(--muted);
  text-align:center;
  font-size:.94rem;
}

.small-note{
  color:var(--muted);
  font-size:.9rem;
  line-height:1.55;
}

/* =========================
   MODO PROFESOR
========================= */
.teacher-mode{
  margin-top:16px;
  background:linear-gradient(180deg, rgba(124,58,237,.10), rgba(124,58,237,.04));
  border:1px solid rgba(167,139,250,.22);
  border-radius:20px;
  padding:16px;
}

.teacher-title{
  margin:0 0 12px;
  color:#ede9fe;
  font-size:1rem;
  font-weight:800;
}

.teacher-toolbar{
  display:grid;
  gap:12px;
  margin-bottom:14px;
}

.teacher-field label{
  display:block;
  margin-bottom:6px;
  font-weight:700;
}

.teacher-field select{
  width:100%;
  border:none;
  outline:none;
  padding:12px 14px;
  border-radius:14px;
  background:#0e1730;
  color:var(--text);
  border:1px solid rgba(255,255,255,.08);
  font:inherit;
}

.teacher-buttons{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
}

.teacher-btn{
  appearance:none;
  border:none;
  border-radius:14px;
  padding:10px 14px;
  font:inherit;
  font-weight:700;
  cursor:pointer;
  transition:.2s ease;
}

.teacher-btn.primary{
  background:linear-gradient(135deg,#8b5cf6,#7c3aed);
  color:white;
  box-shadow:0 10px 24px rgba(124,58,237,.24);
}

.teacher-btn.secondary{
  background:rgba(255,255,255,.05);
  color:var(--text);
  border:1px solid rgba(255,255,255,.08);
}

.teacher-btn:hover{
  transform:translateY(-1px);
}

.teacher-card{
  background:rgba(255,255,255,.035);
  border:1px solid rgba(255,255,255,.08);
  border-radius:18px;
  padding:14px;
}

.teacher-prompt{
  font-weight:800;
  color:#f5f3ff;
  line-height:1.55;
  margin-bottom:12px;
}

.teacher-subtext{
  color:var(--muted);
  font-size:.92rem;
  line-height:1.5;
  margin-bottom:12px;
}

.answer-list{
  display:grid;
  gap:10px;
  margin-bottom:12px;
}

.answer-option{
  display:flex;
  gap:10px;
  align-items:flex-start;
  padding:12px;
  border-radius:14px;
  background:#0e1730;
  border:1px solid rgba(255,255,255,.08);
  cursor:pointer;
  transition:.2s ease;
}

.answer-option:hover{
  border-color:rgba(139,92,246,.45);
}

.answer-option input{
  margin-top:2px;
  accent-color:#8b5cf6;
}

.teacher-textarea{
  width:100%;
  min-height:88px;
  resize:vertical;
  border:none;
  outline:none;
  padding:12px 14px;
  border-radius:14px;
  background:#0e1730;
  color:var(--text);
  border:1px solid rgba(255,255,255,.08);
  font:inherit;
  line-height:1.5;
}

.teacher-actions{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:12px;
}

.feedback-box{
  margin-top:12px;
  border-radius:14px;
  padding:12px 14px;
  line-height:1.6;
  font-size:.95rem;
}

.feedback-box.success{
  background:linear-gradient(180deg, rgba(34,197,94,.12), rgba(34,197,94,.05));
  border:1px solid rgba(34,197,94,.24);
  color:#dcfce7;
}

.feedback-box.error{
  background:linear-gradient(180deg, rgba(239,68,68,.12), rgba(239,68,68,.05));
  border:1px solid rgba(239,68,68,.24);
  color:#fee2e2;
}

.solution-box{
  margin-top:12px;
  background:linear-gradient(180deg, rgba(96,165,250,.12), rgba(96,165,250,.05));
  border:1px solid rgba(96,165,250,.22);
  border-radius:14px;
  padding:12px 14px;
  color:#dbeafe;
  line-height:1.65;
}

.solution-box strong{
  display:block;
  margin-bottom:6px;
}

.teacher-small{
  color:var(--muted);
  font-size:.9rem;
  line-height:1.5;
  margin-top:10px;
}

.hidden{
  display:none !important;
}

@media (max-width: 1220px){
  .grid{
    grid-template-columns:1fr;
  }
}

@media (max-width: 640px){
  .app{ padding:12px; }
  .hero{ padding:16px; border-radius:22px; }
  .panel{ border-radius:20px; }
  .panel-inner{ padding:14px; }
  .presets{ grid-template-columns:1fr; }
  .segmented{ grid-template-columns:1fr; }
  #canvasHost{ min-height:390px; }
}