/* ==========================================================================
   TEMA VISUAL: BRANCO GELO (#f4f6f9), VERMELHO (#d32f2f / #e53935), 
   PRETO (#111827) E TONS DE CINZA (#334155, #64748b, #e2e8f0)
   ========================================================================== */

:root {
  --bg-ice: #f4f6f9;
  --bg-card: #ffffff;
  --bg-code: #0f172a;
  
  --primary-red: #d32f2f;
  --primary-red-hover: #b71c1c;
  --primary-red-light: #ffebee;
  --accent-red: #e53935;
  
  --text-dark: #111827;
  --text-main: #1f2937;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  
  --border-light: #e2e8f0;
  --border-medium: #cbd5e1;
  
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.12);
  --shadow-red: 0 4px 15px rgba(211, 47, 47, 0.25);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  
  --font-main: 'Inter', system-ui, -apple-system, sans-serif;
  --font-code: 'JetBrains Mono', monospace;
}

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-ice);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* --------------------------------------------------------------------------
   Header
   -------------------------------------------------------------------------- */
.app-header {
  background-color: #ffffff;
  border-bottom: 2px solid var(--border-light);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.brand {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.brand-badge {
  background-color: var(--primary-red);
  color: #ffffff;
  font-family: var(--font-code);
  font-weight: 800;
  font-size: 0.85rem;
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius-sm);
  letter-spacing: 1px;
  box-shadow: var(--shadow-red);
}

.brand-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-dark);
  line-height: 1.2;
}

.brand-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.progress-pill {
  background-color: var(--bg-ice);
  border: 1px solid var(--border-medium);
  padding: 0.5rem 1rem;
  border-radius: 999px;
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.progress-text {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-dark);
}

.progress-bar-bg {
  width: 100px;
  height: 8px;
  background-color: var(--border-light);
  border-radius: 4px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--primary-red), var(--accent-red));
  border-radius: 4px;
  transition: width 0.4s ease;
}

.progress-count {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 600;
}

/* Buttons */
.btn {
  font-family: var(--font-main);
  font-size: 0.875rem;
  font-weight: 600;
  padding: 0.55rem 1.1rem;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.2s ease;
}

.btn-primary {
  background-color: var(--primary-red);
  color: #ffffff;
  box-shadow: var(--shadow-red);
}

.btn-primary:hover {
  background-color: var(--primary-red-hover);
  transform: translateY(-1px);
}

.btn-outline {
  background-color: transparent;
  border: 1px solid var(--border-medium);
  color: var(--text-main);
}

.btn-outline:hover {
  background-color: var(--bg-ice);
  border-color: var(--text-muted);
}

.btn-sm {
  font-size: 0.775rem;
  padding: 0.35rem 0.75rem;
}

/* --------------------------------------------------------------------------
   Layout Main
   -------------------------------------------------------------------------- */
.main-layout {
  max-width: 1440px;
  margin: 0 auto;
  width: 100%;
  display: flex;
  flex: 1;
}

/* Sidebar */
.sidebar {
  width: 320px;
  background-color: #ffffff;
  border-right: 1px solid var(--border-light);
  display: flex;
  flex-direction: column;
  height: calc(100vh - 73px);
  position: sticky;
  top: 73px;
  overflow-y: auto;
}

.sidebar-header {
  padding: 1.25rem;
  border-bottom: 1px solid var(--border-light);
}

.sidebar-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 0.75rem;
}

.filter-buttons {
  display: flex;
  gap: 0.35rem;
}

.btn-filter {
  flex: 1;
  background: var(--bg-ice);
  border: 1px solid var(--border-light);
  padding: 0.35rem 0.5rem;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-filter.active, .btn-filter:hover {
  background-color: var(--text-dark);
  color: #ffffff;
  border-color: var(--text-dark);
}

.exercise-nav {
  padding: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  flex: 1;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text-main);
  font-size: 0.85rem;
  font-weight: 500;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  cursor: pointer;
}

.nav-item:hover {
  background-color: var(--bg-ice);
  border-color: var(--border-light);
}

.nav-item.active {
  background-color: var(--primary-red-light);
  color: var(--primary-red);
  font-weight: 700;
  border-color: rgba(211, 47, 47, 0.2);
}

.nav-item-num {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background-color: var(--bg-ice);
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: var(--font-code);
}

.nav-item.completed .nav-item-num {
  background-color: var(--primary-red);
  color: #ffffff;
}

.nav-item-title {
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sidebar-footer {
  padding: 1rem;
  border-top: 1px solid var(--border-light);
}

.tip-card {
  background-color: var(--bg-ice);
  border: 1px dashed var(--border-medium);
  border-radius: var(--radius-sm);
  padding: 0.75rem;
  display: flex;
  gap: 0.6rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Content Area */
.content-area {
  flex: 1;
  padding: 2rem;
  max-width: 1080px;
  margin: 0 auto;
  width: 100%;
}

.welcome-banner {
  background: #ffffff;
  border: 1px solid var(--border-light);
  border-left: 5px solid var(--primary-red);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-sm);
}

.banner-badge {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--primary-red);
  letter-spacing: 1px;
  margin-bottom: 0.5rem;
  font-family: var(--font-code);
}

.welcome-banner h2 {
  font-size: 1.5rem;
  color: var(--text-dark);
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.welcome-banner p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 1.25rem;
}

.banner-features {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.feature-tag {
  background-color: var(--bg-ice);
  border: 1px solid var(--border-light);
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-dark);
}

/* --------------------------------------------------------------------------
   Exercise Cards
   -------------------------------------------------------------------------- */
.exercises-list {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.exercise-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  scroll-margin-top: 90px;
}

.exercise-card.completed-card {
  border-color: rgba(211, 47, 47, 0.4);
}

.card-header {
  padding: 1.25rem 1.5rem;
  background-color: #ffffff;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.card-header-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.exercise-number-badge {
  background-color: var(--text-dark);
  color: #ffffff;
  font-family: var(--font-code);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-sm);
}

.exercise-title {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-dark);
}

.card-header-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.checkbox-container {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  user-select: none;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-dark);
  background: var(--bg-ice);
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  transition: all 0.2s ease;
}

.checkbox-container:hover {
  border-color: var(--primary-red);
}

.checkbox-container input {
  accent-color: var(--primary-red);
  width: 16px;
  height: 16px;
}

.card-body {
  padding: 1.75rem;
}

/* Analogy Visual Box */
.analogy-box {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 1.5rem;
  background-color: var(--bg-ice);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  margin-bottom: 1.5rem;
  align-items: center;
}

@media (max-width: 868px) {
  .analogy-box {
    grid-template-columns: 1fr;
  }
}

.analogy-img-wrapper {
  width: 100%;
  height: 200px;
  background-color: #ffffff;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-medium);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.analogy-img-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.analogy-content {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.analogy-tag {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--primary-red);
  letter-spacing: 0.5px;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.analogy-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-dark);
}

.analogy-desc {
  font-size: 0.9rem;
  color: var(--text-main);
  line-height: 1.5;
}

/* Section Subtitles */
.section-subtitle {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* Step list */
.steps-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  margin-bottom: 1.5rem;
}

.step-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: 0.9rem;
  background-color: #ffffff;
  border: 1px solid var(--border-light);
  padding: 0.6rem 0.85rem;
  border-radius: var(--radius-sm);
}

.step-number {
  background-color: var(--text-dark);
  color: #ffffff;
  font-family: var(--font-code);
  font-size: 0.75rem;
  font-weight: 700;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 2px;
}

.inline-code {
  font-family: var(--font-code);
  background-color: var(--bg-ice);
  color: var(--primary-red);
  font-weight: 600;
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  border: 1px solid var(--border-light);
  font-size: 0.85em;
}

/* Code Blocks */
.code-block-wrapper {
  background-color: var(--bg-code);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 1.5rem;
  border: 1px solid #334155;
}

.code-header {
  background-color: #1e293b;
  padding: 0.5rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #94a3b8;
  font-family: var(--font-code);
  font-size: 0.8rem;
  border-bottom: 1px solid #334155;
}

.code-content {
  padding: 1rem 1.25rem;
  overflow-x: auto;
  color: #e2e8f0;
  font-family: var(--font-code);
  font-size: 0.85rem;
  line-height: 1.6;
}

.btn-copy {
  background-color: transparent;
  border: 1px solid #475569;
  color: #cbd5e1;
  font-size: 0.75rem;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-copy:hover {
  background-color: #334155;
  color: #ffffff;
}

/* Card Actions */
.card-actions-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-light);
  flex-wrap: wrap;
}

.solution-box {
  width: 100%;
  background-color: #fff8f8;
  border: 1px solid rgba(211, 47, 47, 0.2);
  border-radius: var(--radius-md);
  padding: 1rem;
  margin-top: 1rem;
  display: none;
}

.solution-box.open {
  display: block;
}

.solution-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--primary-red);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* --------------------------------------------------------------------------
   Terminal Simulator Drawer
   -------------------------------------------------------------------------- */
.floating-terminal-btn {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background-color: var(--text-dark);
  color: #ffffff;
  border: 2px solid var(--primary-red);
  padding: 0.85rem 1.4rem;
  border-radius: 999px;
  font-family: var(--font-main);
  font-weight: 700;
  font-size: 0.9rem;
  cursor: pointer;
  box-shadow: var(--shadow-lg), var(--shadow-red);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  z-index: 90;
  transition: all 0.3s ease;
}

.floating-terminal-btn:hover {
  background-color: var(--primary-red);
  transform: translateY(-3px);
}

.terminal-drawer {
  position: fixed;
  bottom: 0;
  right: 0;
  left: 0;
  height: 380px;
  background-color: #0f172a;
  border-top: 3px solid var(--primary-red);
  box-shadow: 0 -10px 30px rgba(0, 0, 0, 0.3);
  z-index: 200;
  display: flex;
  flex-direction: column;
  transform: translateY(100%);
  transition: transform 0.3s ease;
}

.terminal-drawer.open {
  transform: translateY(0);
}

.terminal-drawer-header {
  background-color: #1e293b;
  padding: 0.6rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid #334155;
}

.terminal-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.terminal-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.terminal-dot.red { background-color: #ef4444; }
.terminal-dot.gray { background-color: #f59e0b; }
.terminal-dot.dark { background-color: #10b981; }

.terminal-name {
  color: #e2e8f0;
  font-family: var(--font-code);
  font-size: 0.85rem;
  font-weight: 600;
  margin-left: 0.5rem;
}

.terminal-drawer-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-icon {
  background: transparent;
  border: none;
  color: #94a3b8;
  font-size: 1rem;
  cursor: pointer;
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
}

.btn-icon:hover {
  background-color: #334155;
  color: #ffffff;
}

.terminal-drawer-body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  flex: 1;
  overflow: hidden;
}

@media (max-width: 768px) {
  .terminal-drawer-body {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
  }
}

.terminal-editor-pane, .terminal-output-pane {
  display: flex;
  flex-direction: column;
  border-right: 1px solid #334155;
}

.pane-header {
  background-color: #0f172a;
  padding: 0.4rem 1rem;
  color: #94a3b8;
  font-family: var(--font-code);
  font-size: 0.75rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid #1e293b;
}

#terminal-code-input {
  flex: 1;
  background-color: #0f172a;
  color: #f8fafc;
  border: none;
  padding: 1rem;
  font-family: var(--font-code);
  font-size: 0.85rem;
  resize: none;
  outline: none;
  line-height: 1.6;
}

.console-output {
  flex: 1;
  background-color: #020617;
  color: #38bdf8;
  padding: 1rem;
  font-family: var(--font-code);
  font-size: 0.85rem;
  overflow-y: auto;
  white-space: pre-wrap;
  margin: 0;
}

/* Print Style */
@media print {
  .app-header, .sidebar, .floating-terminal-btn, .terminal-drawer, .card-actions-bar {
    display: none !important;
  }
  .main-layout {
    display: block;
  }
  .content-area {
    padding: 0;
    max-width: 100%;
  }
  .exercise-card {
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #000;
    margin-bottom: 2rem;
  }
}