/* ==========================================================================
   ACADEMIA Y JUEGO DE REGLA DE TRES - DIGITAL KIDS ACADEMY
   Simple Directa · Simple Inversa · Compuesta Nivel 1 · Compuesta Nivel 2
   ========================================================================== */

:root {
  --bg-dark: #070f26;
  --bg-gradient: radial-gradient(circle at 20% 20%, #13285c 0%, #070f26 65%, #040817 100%);
  --panel-bg: rgba(11, 22, 52, 0.94);
  --card-bg: rgba(19, 34, 72, 0.95);
  --card-hover: rgba(28, 48, 98, 0.98);
  --primary: #f97316;
  --primary-dark: #ea580c;
  --gold: #ffd60a;
  --gold-soft: rgba(255, 214, 10, 0.16);
  --green: #22c55e;
  --green-soft: rgba(34, 197, 94, 0.18);
  --red: #ef4444;
  --red-soft: rgba(239, 68, 68, 0.18);
  --blue: #38bdf8;
  --blue-soft: rgba(56, 189, 248, 0.16);
  --purple: #a855f7;
  --purple-soft: rgba(168, 85, 247, 0.18);
  --text-light: #f8fafc;
  --text-muted: #cbd5e1;
  --font-title: 'Fredoka', sans-serif;
  --font-body: 'Nunito', sans-serif;
  --border-subtle: rgba(255, 255, 255, 0.15);
}

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

html, body {
  width: 100%;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--text-light);
  background: var(--bg-gradient);
  background-attachment: fixed;
  overflow-x: hidden;
}

.hidden {
  display: none !important;
}

/* ==========================================================================
   BARRA SUPERIOR
   ========================================================================== */
.top-bar {
  position: sticky;
  top: 0;
  z-index: 100;
  min-height: 70px;
  background: linear-gradient(90deg, rgba(6, 13, 33, 0.97), rgba(15, 29, 64, 0.96));
  border-bottom: 3px solid var(--gold);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 24px;
  backdrop-filter: blur(12px);
  gap: 14px;
  flex-wrap: wrap;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.brand-logo-img {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  border: 2px solid var(--gold);
  object-fit: cover;
}

.brand-logo h1 {
  font-family: var(--font-title);
  font-size: 1.25rem;
  color: var(--gold);
  letter-spacing: 0.5px;
  line-height: 1.1;
}

.brand-logo small {
  font-size: 0.76rem;
  color: #e2e8f0;
  font-weight: 700;
}

.status-pills {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.stat-pill {
  background: rgba(255, 255, 255, 0.08);
  border: 2px solid rgba(255, 255, 255, 0.2);
  padding: 6px 14px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 6px;
}

.stat-pill strong {
  color: var(--gold);
  font-size: 1.02rem;
}

.stat-pill.streak-pill {
  border-color: var(--primary);
  background: rgba(249, 115, 22, 0.18);
}

.stat-pill.score-pill {
  border-color: var(--gold);
  background: var(--gold-soft);
}

.stat-pill.level-pill {
  border-color: var(--blue);
  background: var(--blue-soft);
}

.top-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.btn-top {
  font-family: var(--font-title);
  font-size: 0.88rem;
  padding: 8px 14px;
  border-radius: 12px;
  border: 2px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  cursor: pointer;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: transform 0.15s, background 0.15s, border-color 0.15s;
}

.btn-top:hover {
  transform: translateY(-2px);
  background: rgba(255, 255, 255, 0.18);
  border-color: var(--gold);
}

.btn-top.btn-accent {
  background: linear-gradient(135deg, #f97316, #ea580c);
  border-color: #fdba74;
}

.btn-top.btn-island {
  background: linear-gradient(135deg, #0284c7, #0369a1);
  border-color: #7dd3fc;
}

/* ==========================================================================
   CONTENEDOR PRINCIPAL Y NAVEGACIÓN DE MODOS
   ========================================================================== */
.app-container {
  max-width: 1340px;
  margin: 0 auto;
  padding: 24px 20px 60px;
}

.mode-Zero-banner {
  background: linear-gradient(135deg, rgba(20, 38, 82, 0.95), rgba(11, 21, 50, 0.96));
  border: 2px solid rgba(255, 214, 10, 0.45);
  border-radius: 22px;
  padding: 20px 26px;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.4);
  flex-wrap: wrap;
}

.banner-left {
  display: flex;
  align-items: center;
  gap: 18px;
  flex: 1;
  min-width: 280px;
}

.mascot-mini-badge {
  width: 74px;
  height: 74px;
  border-radius: 18px;
  background: radial-gradient(circle, rgba(255, 214, 10, 0.25), rgba(8, 16, 38, 0.9));
  border: 2px solid var(--gold);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  cursor: pointer;
  transition: transform 0.2s;
}

.mascot-mini-badge:hover {
  transform: scale(1.06) rotate(-3deg);
}

.banner-text h2 {
  font-family: var(--font-title);
  font-size: 1.55rem;
  color: var(--gold);
  margin-bottom: 4px;
}

.banner-text p {
  color: var(--text-muted);
  font-size: 0.96rem;
  line-height: 1.45;
}

.main-nav-tabs {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.main-tab-btn {
  font-family: var(--font-title);
  font-size: 0.98rem;
  padding: 12px 20px;
  border-radius: 14px;
  border: 2px solid rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.07);
  color: var(--text-light);
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  gap: 8px;
}

.main-tab-btn:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
}

.main-tab-btn.active {
  background: linear-gradient(135deg, var(--gold), #f59e0b);
  color: #070f26;
  border-color: #fff;
  font-weight: 700;
  box-shadow: 0 6px 20px rgba(255, 214, 10, 0.35);
}

/* ==========================================================================
   SELECTOR DE LOS 4 NIVELES (2 SIMPLE + 2 COMPUESTA)
   ========================================================================== */
.levels-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(275px, 1fr));
  gap: 16px;
  margin-bottom: 26px;
}

.level-card {
  background: var(--card-bg);
  border: 2px solid var(--border-subtle);
  border-radius: 18px;
  padding: 18px;
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 12px;
}

.level-card:hover {
  transform: translateY(-4px);
  border-color: var(--gold);
  background: var(--card-hover);
}

.level-card.active {
  border-color: var(--gold);
  box-shadow: 0 0 0 3px rgba(255, 214, 10, 0.28), 0 12px 26px rgba(0, 0, 0, 0.45);
  background: linear-gradient(160deg, rgba(30, 54, 110, 0.96), rgba(15, 28, 62, 0.96));
}

.level-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.level-badge {
  font-family: var(--font-title);
  font-size: 0.78rem;
  padding: 4px 11px;
  border-radius: 999px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.badge-directa {
  background: var(--green-soft);
  color: #4ade80;
  border: 1px solid #22c55e;
}

.badge-inversa {
  background: var(--blue-soft);
  color: #7dd3fc;
  border: 1px solid #38bdf8;
}

.badge-comp1 {
  background: var(--purple-soft);
  color: #d8b4fe;
  border: 1px solid #a855f7;
}

.badge-comp2 {
  background: rgba(249, 115, 22, 0.2);
  color: #fdba74;
  border: 1px solid #f97316;
}

.level-digits-tag {
  font-size: 0.76rem;
  font-weight: 800;
  color: var(--gold);
  background: rgba(255, 214, 10, 0.12);
  padding: 3px 9px;
  border-radius: 8px;
}

.level-card h3 {
  font-family: var(--font-title);
  font-size: 1.16rem;
  color: #fff;
}

.level-card p {
  font-size: 0.87rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.level-progress-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  font-weight: 800;
  color: #e2e8f0;
  padding-top: 8px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.level-progress-stars {
  color: var(--gold);
}

/* ==========================================================================
   SECCIÓN 1: ACADEMIA DE TÉCNICAS Y ECUACIONES (APRENDE PRIMERO)
   ========================================================================== */
.theory-workspace {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 22px;
  align-items: start;
}

@media (max-width: 1024px) {
  .theory-workspace {
    grid-template-columns: 1fr;
  }
}

.theory-panel, .interactive-demo-panel {
  background: var(--panel-bg);
  border: 2px solid rgba(255, 255, 255, 0.16);
  border-radius: 22px;
  padding: 24px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.38);
}

.panel-header-tag {
  display: inline-block;
  font-family: var(--font-title);
  font-size: 0.8rem;
  color: var(--gold);
  background: var(--gold-soft);
  border: 1px solid rgba(255, 214, 10, 0.4);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 10px;
}

.theory-panel h2, .interactive-demo-panel h2 {
  font-family: var(--font-title);
  font-size: 1.45rem;
  color: #fff;
  margin-bottom: 10px;
}

.theory-intro {
  color: var(--text-muted);
  font-size: 0.96rem;
  line-height: 1.55;
  margin-bottom: 18px;
}

/* Tarjetas de Reglas y Ecuaciones */
.technique-box {
  background: rgba(255, 255, 255, 0.05);
  border-left: 5px solid var(--gold);
  border-radius: 14px;
  padding: 16px 18px;
  margin-bottom: 16px;
}

.technique-box h4 {
  font-family: var(--font-title);
  color: var(--gold);
  font-size: 1.08rem;
  margin-bottom: 8px;
}

.technique-box p, .technique-box li {
  font-size: 0.93rem;
  line-height: 1.5;
  color: #e2e8f0;
}

.technique-box ul {
  padding-left: 20px;
  margin-top: 6px;
}

.technique-box li {
  margin-bottom: 5px;
}

/* Visualizador de Ecuación y Esquema de Proporción */
.equation-showcase {
  background: linear-gradient(145deg, rgba(8, 16, 38, 0.95), rgba(18, 33, 70, 0.95));
  border: 2px solid rgba(56, 189, 248, 0.45);
  border-radius: 18px;
  padding: 18px;
  margin: 16px 0;
  text-align: center;
}

.equation-showcase-title {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.7px;
  color: var(--blue);
  font-weight: 800;
  margin-bottom: 12px;
}

.proportion-diagram {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.prop-col {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 12px;
  padding: 10px 16px;
  min-width: 120px;
}

.prop-col-header {
  font-family: var(--font-title);
  font-size: 0.86rem;
  color: var(--gold);
  margin-bottom: 6px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  padding-bottom: 4px;
}

.prop-row-val {
  font-size: 1.05rem;
  font-weight: 800;
  padding: 4px 0;
  color: #fff;
}

.prop-row-val.unknown-x {
  color: var(--primary);
  font-size: 1.2rem;
}

.sign-badge {
  display: inline-block;
  padding: 1px 7px;
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 900;
  margin-left: 6px;
}

.sign-plus {
  background: rgba(34, 197, 94, 0.25);
  color: #4ade80;
  border: 1px solid #22c55e;
}

.sign-minus {
  background: rgba(239, 68, 68, 0.25);
  color: #f87171;
  border: 1px solid #ef4444;
}

/* Fracción Matemática grande */
.formula-fraction-box {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  background: rgba(255, 214, 10, 0.1);
  border: 2px solid var(--gold);
  border-radius: 16px;
  padding: 12px 24px;
  font-family: var(--font-title);
  font-size: 1.25rem;
  color: #fff;
}

.math-frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  vertical-align: middle;
}

.math-frac-num {
  border-bottom: 2px solid var(--gold);
  padding: 0 10px 4px;
  color: #4ade80;
}

.math-frac-den {
  padding: 4px 10px 0;
  color: #f87171;
}

/* Simulador Guiado Paso a Paso (En la columna derecha de Aprende) */
.demo-problem-box {
  background: rgba(255, 255, 255, 0.06);
  border: 2px solid rgba(255, 214, 10, 0.35);
  border-radius: 16px;
  padding: 16px;
  margin-bottom: 18px;
}

.demo-problem-box h4 {
  font-family: var(--font-title);
  color: var(--gold);
  margin-bottom: 6px;
  font-size: 1.05rem;
}

.demo-problem-text {
  font-size: 0.98rem;
  line-height: 1.55;
  color: #fff;
}

.demo-steps-nav {
  display: flex;
  gap: 8px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.step-pill-btn {
  flex: 1;
  min-width: 110px;
  padding: 9px 12px;
  border-radius: 11px;
  border: 2px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-muted);
  font-family: var(--font-title);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.18s;
}

.step-pill-btn.active {
  border-color: var(--gold);
  background: var(--gold-soft);
  color: var(--gold);
}

.step-pill-btn.done {
  border-color: var(--green);
  color: #4ade80;
}

.demo-step-stage {
  background: rgba(7, 15, 38, 0.85);
  border: 2px solid rgba(255, 255, 255, 0.14);
  border-radius: 16px;
  padding: 18px;
  min-height: 220px;
  margin-bottom: 16px;
}

.demo-step-stage h5 {
  font-family: var(--font-title);
  font-size: 1.1rem;
  color: var(--blue);
  margin-bottom: 10px;
}

.demo-controls-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

/* ==========================================================================
   SECCIÓN 2: PRÁCTICA INTERACTIVA POR NIVELES
   ========================================================================== */
.practice-workspace {
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 22px;
  align-items: start;
}

@media (max-width: 1060px) {
  .practice-workspace {
    grid-template-columns: 1fr;
  }
}

.exercise-card, .workbench-card {
  background: var(--panel-bg);
  border: 2px solid rgba(255, 255, 255, 0.16);
  border-radius: 22px;
  padding: 24px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4);
}

.exercise-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.exercise-counter-pills {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.ex-dot {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  border: 2px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.06);
  color: #fff;
  font-family: var(--font-title);
  font-size: 0.9rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.15s;
}

.ex-dot.active {
  border-color: var(--gold);
  background: var(--gold);
  color: #070f26;
  font-weight: 800;
}

.ex-dot.solved {
  border-color: var(--green);
  background: var(--green-soft);
  color: #4ade80;
}

.problem-statement-box {
  background: linear-gradient(145deg, rgba(22, 41, 88, 0.92), rgba(11, 22, 52, 0.95));
  border: 2px solid rgba(255, 214, 10, 0.45);
  border-radius: 18px;
  padding: 20px;
  margin-bottom: 20px;
}

.problem-context-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  color: var(--gold);
  background: rgba(255, 214, 10, 0.14);
  padding: 4px 10px;
  border-radius: 8px;
  margin-bottom: 8px;
}

.problem-statement-text {
  font-size: 1.12rem;
  line-height: 1.6;
  color: #fff;
  font-weight: 700;
}

.problem-statement-text strong {
  color: var(--gold);
  background: rgba(255, 214, 10, 0.12);
  padding: 1px 6px;
  border-radius: 6px;
}

/* Tabla Interactiva de Magnitudes del Problema */
.magnitudes-table-wrap {
  margin-bottom: 20px;
  overflow-x: auto;
}

.magnitudes-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 8px;
}

.magnitudes-table th {
  background: rgba(56, 189, 248, 0.15);
  border: 2px solid rgba(56, 189, 248, 0.4);
  border-radius: 12px;
  padding: 10px 12px;
  font-family: var(--font-title);
  font-size: 0.95rem;
  color: var(--blue);
  text-align: center;
}

.magnitudes-table td {
  background: rgba(255, 255, 255, 0.05);
  border: 2px solid rgba(255, 255, 255, 0.14);
  border-radius: 12px;
  padding: 12px;
  text-align: center;
  font-size: 1.06rem;
  font-weight: 800;
  color: #fff;
}

.magnitudes-table td.cell-unknown {
  border-color: var(--primary);
  background: rgba(249, 115, 22, 0.18);
  color: var(--gold);
  font-family: var(--font-title);
  font-size: 1.2rem;
}

/* Pasos Guiados dentro del Ejercicio */
.solve-step-card {
  background: rgba(255, 255, 255, 0.04);
  border: 2px solid rgba(255, 255, 255, 0.14);
  border-radius: 16px;
  padding: 16px 18px;
  margin-bottom: 16px;
  transition: border-color 0.2s;
}

.solve-step-card.step-correct {
  border-color: var(--green);
  background: rgba(34, 197, 94, 0.07);
}

.solve-step-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
  gap: 8px;
}

.solve-step-title {
  font-family: var(--font-title);
  font-size: 1.02rem;
  color: var(--gold);
}

.relation-selectors-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 12px;
}

.rel-selector-item {
  background: rgba(7, 15, 38, 0.75);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 12px;
  padding: 12px;
}

.rel-selector-item label {
  display: block;
  font-size: 0.86rem;
  font-weight: 800;
  color: #e2e8f0;
  margin-bottom: 8px;
}

.rel-btn-group {
  display: flex;
  gap: 8px;
}

.rel-choice-btn {
  flex: 1;
  padding: 8px 10px;
  border-radius: 10px;
  border: 2px solid rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.06);
  color: #fff;
  font-family: var(--font-title);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.15s;
}

.rel-choice-btn:hover {
  border-color: var(--gold);
}

.rel-choice-btn.selected-D {
  background: var(--green-soft);
  border-color: var(--green);
  color: #4ade80;
}

.rel-choice-btn.selected-I {
  background: var(--blue-soft);
  border-color: var(--blue);
  color: #7dd3fc;
}

/* Paso 2: Selección de Ecuación Planteada */
.equation-options-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.eq-option-btn {
  background: rgba(7, 15, 38, 0.82);
  border: 2px solid rgba(255, 255, 255, 0.18);
  border-radius: 14px;
  padding: 12px 14px;
  color: #fff;
  cursor: pointer;
  text-align: center;
  font-family: var(--font-body);
  font-size: 0.96rem;
  font-weight: 800;
  transition: all 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 76px;
}

.eq-option-btn:hover {
  border-color: var(--gold);
  background: rgba(255, 214, 10, 0.1);
}

.eq-option-btn.selected {
  border-color: var(--gold);
  background: rgba(255, 214, 10, 0.18);
  box-shadow: 0 0 0 2px rgba(255, 214, 10, 0.3);
}

.eq-option-btn.correct {
  border-color: var(--green);
  background: var(--green-soft);
}

.eq-option-btn.wrong {
  border-color: var(--red);
  background: var(--red-soft);
}

/* Paso 3: Respuesta Final */
.final-answer-row {
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}

.answer-input-wrap {
  position: relative;
  flex: 1;
  min-width: 200px;
  display: flex;
  align-items: center;
}

.answer-input {
  width: 100%;
  padding: 14px 18px;
  border-radius: 14px;
  border: 2px solid var(--gold);
  background: rgba(5, 11, 28, 0.95);
  color: var(--gold);
  font-family: var(--font-title);
  font-size: 1.25rem;
  outline: none;
}

.answer-input:focus {
  box-shadow: 0 0 0 3px rgba(255, 214, 10, 0.3);
}

.answer-unit-badge {
  margin-left: 10px;
  font-weight: 800;
  color: var(--text-muted);
  font-size: 0.98rem;
}

.quick-choices-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.quick-ans-btn {
  padding: 11px 14px;
  border-radius: 12px;
  border: 2px solid rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.07);
  color: #fff;
  font-family: var(--font-title);
  font-size: 1.02rem;
  cursor: pointer;
  transition: all 0.15s;
}

.quick-ans-btn:hover {
  border-color: var(--gold);
  background: rgba(255, 214, 10, 0.16);
  transform: translateY(-2px);
}

/* Botones principales */
.btn-primary {
  font-family: var(--font-title);
  font-size: 1rem;
  padding: 13px 22px;
  border-radius: 14px;
  border: 2px solid #fdba74;
  background: linear-gradient(135deg, #f97316, #ea580c);
  color: #fff;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
  box-shadow: 0 6px 18px rgba(249, 115, 22, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(249, 115, 22, 0.5);
}

.btn-secondary {
  font-family: var(--font-title);
  font-size: 0.94rem;
  padding: 11px 18px;
  border-radius: 12px;
  border: 2px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.09);
  color: #fff;
  cursor: pointer;
  transition: all 0.15s;
}

.btn-secondary:hover {
  border-color: var(--gold);
  background: rgba(255, 255, 255, 0.16);
}

.btn-success {
  font-family: var(--font-title);
  font-size: 1rem;
  padding: 13px 22px;
  border-radius: 14px;
  border: 2px solid #86efac;
  background: linear-gradient(135deg, #22c55e, #16a34a);
  color: #052e16;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.15s;
}

.btn-success:hover {
  transform: translateY(-2px);
}

/* Feedback y Explicación Paso a Paso */
.feedback-banner {
  border-radius: 16px;
  padding: 16px 18px;
  margin-top: 16px;
  font-weight: 700;
  line-height: 1.5;
}

.feedback-banner.ok {
  background: var(--green-soft);
  border: 2px solid var(--green);
  color: #bbf7d0;
}

.feedback-banner.err {
  background: var(--red-soft);
  border: 2px solid var(--red);
  color: #fecaca;
}

.solution-breakdown-box {
  background: rgba(7, 15, 38, 0.92);
  border: 2px solid var(--blue);
  border-radius: 16px;
  padding: 18px;
  margin-top: 16px;
}

.solution-breakdown-box h4 {
  font-family: var(--font-title);
  color: var(--gold);
  margin-bottom: 10px;
}

.solution-breakdown-box ol {
  padding-left: 20px;
}

.solution-breakdown-box li {
  margin-bottom: 8px;
  line-height: 1.5;
  color: #e2e8f0;
}

/* ==========================================================================
   COLUMNA DERECHA DE PRÁCTICA: PIZARRA DE CÁLCULO Y CHULETA DE FÓRMULAS
   ========================================================================== */
.workbench-card h3 {
  font-family: var(--font-title);
  font-size: 1.2rem;
  color: var(--gold);
  margin-bottom: 8px;
}

.workbench-sub {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.calc-box {
  background: rgba(6, 12, 30, 0.9);
  border: 2px solid rgba(255, 255, 255, 0.16);
  border-radius: 16px;
  padding: 14px;
  margin-bottom: 18px;
}

.calc-display {
  width: 100%;
  background: rgba(15, 27, 58, 0.95);
  border: 2px solid rgba(56, 189, 248, 0.4);
  border-radius: 12px;
  padding: 10px 14px;
  color: var(--gold);
  font-family: monospace;
  font-size: 1.25rem;
  text-align: right;
  margin-bottom: 10px;
  min-height: 46px;
  word-break: break-all;
}

.calc-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.calc-btn {
  padding: 10px;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  font-family: var(--font-title);
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.12s;
}

.calc-btn:hover {
  background: rgba(255, 255, 255, 0.2);
}

.calc-btn.op {
  background: rgba(56, 189, 248, 0.2);
  color: var(--blue);
  border-color: rgba(56, 189, 248, 0.4);
}

.calc-btn.eq {
  background: var(--gold);
  color: #070f26;
  font-weight: 800;
}

.calc-btn.clear {
  background: rgba(239, 68, 68, 0.25);
  color: #fca5a5;
}

.scratchpad-textarea {
  width: 100%;
  min-height: 110px;
  border-radius: 12px;
  border: 2px solid rgba(255, 255, 255, 0.16);
  background: rgba(5, 11, 28, 0.85);
  color: #e2e8f0;
  padding: 12px;
  font-family: monospace;
  font-size: 0.95rem;
  resize: vertical;
  margin-bottom: 16px;
}

.quick-cheat-card {
  background: rgba(255, 214, 10, 0.07);
  border: 1px solid rgba(255, 214, 10, 0.35);
  border-radius: 14px;
  padding: 14px;
  font-size: 0.88rem;
  line-height: 1.5;
}

.quick-cheat-card h4 {
  font-family: var(--font-title);
  color: var(--gold);
  margin-bottom: 6px;
}