/* ==========================================================================
   第四章 無線網路通訊入門 (Wireless Network Communications)
   專業互動式教學介面樣式表
   設計主色調：深青綠 (#075B5A)、淺綠底 (#E5F2EF)、珊瑚紅 (#F26B5B)、青藍 (#22B8CF)
   無任何外部庫依賴 · 現代純 CSS3 · 100% 響應式佈局 (RWD)
   ========================================================================== */

:root {
  /* 簡報規劃指定色彩系統 */
  --primary: #075B5A;          /* 深青綠 - 主色、重點帶、標題強調 */
  --primary-dark: #043837;     /* 更深青綠 - 懸浮與邊界 */
  --primary-light: #E5F2EF;    /* 淺綠底 - 提示卡、標籤背板 */
  --primary-border: #8EBFB9;   /* 柔和青綠邊框 */
  
  --text-main: #112326;        /* 內文深青墨黑 */
  --text-muted: #5F7073;       /* 次要灰 - 輔助說明文字 */
  
  --coral: #F26B5B;            /* 強調珊瑚紅 - 「先用白話說」等小標 */
  --coral-light: #FDF0EE;      /* 珊瑚紅淺色背板 */
  --coral-border: #F9C3BC;
  
  --cyan: #22B8CF;             /* 點綴青藍 - 訊號、波形、高亮 */
  --cyan-light: #E8F8FA;
  
  --secondary: #475569;
  --secondary-light: #F8FAFC;
  
  --success: #10B981;
  --success-bg: #ECFDF5;
  --success-border: #A7F3D0;
  
  --warning: #F59E0B;
  --warning-bg: #FFFBEB;
  --warning-border: #FDE68A;
  
  --danger: #EF4444;
  --danger-bg: #FEF2F2;
  --danger-border: #FECACA;
  
  --gray-50: #F7FAF9;
  --gray-100: #EEF3F2;
  --gray-200: #DFE7E5;
  --gray-300: #CBD5D3;
  --gray-400: #94A3A1;
  --gray-500: #647472;
  --gray-600: #475553;
  --gray-700: #334140;
  --gray-800: #1E2928;
  --gray-900: #0F1716;

  --font-sans: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: 'JetBrains Mono', Consolas, "Courier New", monospace;
  
  --shadow-sm: 0 1px 2px 0 rgba(7, 91, 90, 0.05);
  --shadow: 0 2px 4px -1px rgba(7, 91, 90, 0.08), 0 1px 2px -1px rgba(7, 91, 90, 0.05);
  --shadow-md: 0 4px 8px -2px rgba(7, 91, 90, 0.12), 0 2px 4px -2px rgba(7, 91, 90, 0.06);
  --shadow-lg: 0 12px 20px -4px rgba(7, 91, 90, 0.15), 0 4px 8px -4px rgba(7, 91, 90, 0.08);
  
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;
}

/* Reset & Base Setup */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  font-family: var(--font-sans);
  background-color: var(--gray-50);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  width: 100%;
  max-width: 100vw;
  overflow-x: hidden;
}

code, pre, .font-mono {
  font-family: var(--font-mono);
}

/* Utilities */
.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.justify-center { justify-content: center; }
.flex-wrap { flex-wrap: wrap; }
.gap-1 { gap: 0.25rem; }
.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 0.75rem; }
.gap-4 { gap: 1rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }
.mt-6 { margin-top: 1.5rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.font-bold { font-weight: 700; }
.font-medium { font-weight: 500; }
.text-muted { color: var(--text-muted); }
.text-primary { color: var(--primary); }
.text-coral { color: var(--coral); }
.text-cyan { color: var(--cyan); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.hidden { display: none !important; }

/* Grid Layouts */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.25rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}

/* Header Banner */
.site-header {
  background: linear-gradient(135deg, #053C3B 0%, #075B5A 50%, #0F766E 100%);
  color: #ffffff;
  padding: 2.5rem 1.5rem 2rem;
  box-shadow: 0 4px 20px rgba(7, 91, 90, 0.25);
  position: relative;
  overflow: hidden;
}

.site-header::after {
  content: "";
  position: absolute;
  top: -50px;
  right: -50px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(34, 184, 207, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.header-container {
  max-width: 1280px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.header-badge-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 0.75rem;
}

.header-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(8px);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.header-badge.coral-badge {
  background: rgba(242, 107, 91, 0.25);
  border-color: rgba(242, 107, 91, 0.5);
}

.header-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.35rem;
  letter-spacing: -0.02em;
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.header-title span {
  font-size: 1.15rem;
  font-weight: 400;
  opacity: 0.88;
  font-family: var(--font-mono);
}

.header-subtitle {
  font-size: 1.1rem;
  font-weight: 600;
  color: #A7F3D0;
  margin-bottom: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.header-desc {
  font-size: 1rem;
  opacity: 0.92;
  max-width: 920px;
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.header-stats-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.stat-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  backdrop-filter: blur(4px);
}

.stat-pill#global-quiz-pill {
  background: rgba(242, 107, 91, 0.2);
  border-color: rgba(242, 107, 91, 0.4);
}

/* Sticky Navigation Bar */
.nav-bar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #ffffff;
  border-bottom: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
}

.nav-wrapper {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  position: relative;
  padding: 0 0.5rem;
}

.nav-container {
  display: flex;
  overflow-x: auto;
  scroll-behavior: smooth;
  gap: 0.35rem;
  padding: 0.5rem 0.25rem;
  width: 100%;
  scrollbar-width: none;
}

.nav-container::-webkit-scrollbar {
  display: none;
}

.nav-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 0.95rem;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;
  font-family: var(--font-sans);
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.nav-tab:hover {
  background: var(--primary-light);
  color: var(--primary);
}

.nav-tab.active {
  background: var(--primary);
  color: #ffffff;
  box-shadow: 0 2px 6px rgba(7, 91, 90, 0.3);
}

.nav-tab.highlight-tab {
  border-color: var(--coral-border);
}

.nav-tab.highlight-tab.active {
  background: var(--coral);
}

.nav-scroll-btn {
  background: #ffffff;
  border: 1px solid var(--gray-300);
  border-radius: 50%;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1rem;
  color: var(--text-muted);
  box-shadow: var(--shadow-sm);
  z-index: 2;
  transition: all 0.2s ease;
}

.nav-scroll-btn:hover {
  background: var(--gray-100);
  color: var(--primary);
}

/* Main Container */
.main-container {
  max-width: 1280px;
  margin: 1.5rem auto 3rem;
  padding: 0 1rem;
}

.tab-pane {
  display: none;
  animation: fadeIn 0.25s ease-out;
}

.tab-pane.active {
  display: block;
}

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

/* Section Intros */
.section-intro {
  margin-bottom: 1.5rem;
}

.section-badge {
  display: inline-block;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-full);
  margin-bottom: 0.35rem;
  border: 1px solid var(--primary-border);
}

.section-intro h2 {
  font-size: 1.65rem;
  font-weight: 800;
  color: var(--primary-dark);
  margin-bottom: 0.35rem;
}

.section-intro p {
  color: var(--text-muted);
  font-size: 0.95rem;
  max-width: 960px;
  line-height: 1.65;
}

/* Content Cards */
.content-card {
  background: #ffffff;
  border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s ease;
  position: relative;
}

.content-card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--gray-100);
}

.card-header h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.card-header h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--primary);
}

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

/* Tags & Badges */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-sm);
  background: var(--gray-100);
  color: var(--gray-700);
  border: 1px solid var(--gray-300);
}

.tag-teal { background: var(--primary-light); color: var(--primary); border-color: var(--primary-border); }
.tag-coral { background: var(--coral-light); color: var(--coral); border-color: var(--coral-border); }
.tag-cyan { background: var(--cyan-light); color: #0891B2; border-color: #A5F3FC; }
.tag-green { background: var(--success-bg); color: #047857; border-color: var(--success-border); }
.tag-amber { background: var(--warning-bg); color: #B45309; border-color: var(--warning-border); }
.tag-red { background: var(--danger-bg); color: var(--danger); border-color: var(--danger-border); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.55rem 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  font-family: var(--font-sans);
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease-in-out;
  text-decoration: none;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  box-shadow: 0 2px 6px rgba(7, 91, 90, 0.3);
}

.btn-coral {
  background: var(--coral);
  color: #ffffff;
}

.btn-coral:hover {
  background: #E05342;
  box-shadow: 0 2px 6px rgba(242, 107, 91, 0.35);
}

.btn-outline {
  background: #ffffff;
  border-color: var(--gray-300);
  color: var(--text-main);
}

.btn-outline:hover {
  background: var(--gray-100);
  border-color: var(--primary);
  color: var(--primary);
}

.btn-sm {
  padding: 0.35rem 0.7rem;
  font-size: 0.8rem;
}

/* Callout Boxes (名詞卡、教材更正、生活比喻) */
.callout-box {
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin: 1rem 0;
  border-left: 4px solid var(--primary);
  background: var(--gray-50);
}

.callout-box.correction {
  border-left-color: var(--coral);
  background: var(--coral-light);
}

.callout-box.analogy {
  border-left-color: var(--cyan);
  background: var(--cyan-light);
}

.callout-box.takeaway {
  border-left-color: var(--primary);
  background: var(--primary-light);
}

.callout-title {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 0.35rem;
}

.callout-box.correction .callout-title { color: #C53030; }
.callout-box.analogy .callout-title { color: #0E7490; }
.callout-box.takeaway .callout-title { color: var(--primary); }

.callout-content {
  font-size: 0.9rem;
  color: var(--text-main);
  line-height: 1.6;
}

/* Four-grid Term Card (簡報名詞卡專用) */
.term-card {
  border: 1px solid var(--primary-border);
  border-radius: var(--radius);
  background: #ffffff;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.25rem;
}

.term-card-header {
  background: var(--primary);
  color: #ffffff;
  padding: 0.75rem 1.25rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.term-card-header h4 {
  font-size: 1.15rem;
  font-weight: 700;
}

.term-card-header .term-en {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  opacity: 0.85;
}

.term-quad-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--gray-200);
}

.term-cell {
  background: #ffffff;
  padding: 1rem;
}

.term-cell-label {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--coral);
  margin-bottom: 0.25rem;
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

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

/* Data Table */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  text-align: left;
}

.data-table th {
  background: var(--primary);
  color: #ffffff;
  font-weight: 700;
  padding: 0.75rem 0.85rem;
  white-space: nowrap;
}

.data-table td {
  padding: 0.75rem 0.85rem;
  border-bottom: 1px solid var(--gray-200);
  color: var(--text-main);
}

.data-table tr:nth-child(even) td {
  background: var(--gray-50);
}

.data-table tr:hover td {
  background: var(--primary-light);
}

/* Controls & Forms */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.form-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  display: flex;
  justify-content: space-between;
}

.form-select, .form-input {
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  background: #ffffff;
  color: var(--text-main);
  transition: border-color 0.15s ease;
}

.form-select:focus, .form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(7, 91, 90, 0.15);
}

.range-slider {
  -webkit-appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: var(--gray-300);
  outline: none;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--primary);
  cursor: pointer;
  transition: transform 0.1s ease;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.25);
}

.range-slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

/* Simulation Canvas Container */
.sim-canvas-wrapper {
  background: #0B1918;
  border-radius: var(--radius);
  border: 1px solid #1C3331;
  position: relative;
  overflow: hidden;
  box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.4);
}

.sim-canvas {
  width: 100%;
  height: 280px;
  display: block;
}

.sim-overlay-hud {
  position: absolute;
  top: 10px;
  left: 12px;
  right: 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  pointer-events: none;
}

.hud-pill {
  background: rgba(11, 25, 24, 0.85);
  border: 1px solid rgba(34, 184, 207, 0.35);
  color: #E2E8F0;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  padding: 0.3rem 0.65rem;
  border-radius: var(--radius-sm);
  backdrop-filter: blur(4px);
}

/* RSSI Meter Gauge */
.meter-card {
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 1rem;
  text-align: center;
}

.meter-value {
  font-size: 2rem;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--primary);
  line-height: 1.2;
}

.meter-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

.meter-bar-track {
  width: 100%;
  height: 10px;
  background: var(--gray-200);
  border-radius: var(--radius-full);
  margin: 0.75rem 0 0.25rem;
  overflow: hidden;
  display: flex;
}

.meter-bar-fill {
  height: 100%;
  border-radius: var(--radius-full);
  transition: width 0.3s ease, background-color 0.3s ease;
}

/* Quiz Styles */
.quiz-container {
  background: #ffffff;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--gray-200);
}

.quiz-header-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.quiz-score-badge {
  font-size: 0.85rem;
  font-weight: 700;
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-full);
  background: var(--primary-light);
  color: var(--primary);
  border: 1px solid var(--primary-border);
}

.quiz-card {
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1rem;
  transition: border-color 0.2s ease;
}

.quiz-question {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.85rem;
  line-height: 1.55;
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.quiz-option {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  padding: 0.65rem 0.85rem;
  background: #ffffff;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.875rem;
  line-height: 1.45;
  transition: all 0.15s ease;
}

.quiz-option:hover:not(.disabled) {
  background: var(--primary-light);
  border-color: var(--primary-border);
}

.quiz-option.correct {
  background: var(--success-bg) !important;
  border-color: var(--success) !important;
  color: #065F46;
  font-weight: 600;
}

.quiz-option.incorrect {
  background: var(--danger-bg) !important;
  border-color: var(--danger) !important;
  color: #991B1B;
}

.quiz-option.disabled {
  cursor: default;
  opacity: 0.75;
}

.quiz-explanation {
  margin-top: 0.85rem;
  padding: 0.85rem;
  background: #ffffff;
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--primary);
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--text-main);
  display: none;
}

.quiz-explanation.show {
  display: block;
  animation: fadeIn 0.2s ease-out;
}

/* Accordion */
.accordion-toggle {
  cursor: pointer;
  user-select: none;
}

.toggle-arrow {
  display: inline-block;
  transition: transform 0.2s ease;
  font-size: 0.85rem;
}

.toggle-arrow.open {
  transform: rotate(90deg);
}

/* Footer */
.site-footer {
  background: #042E2D;
  color: #D1E5E3;
  padding: 2.5rem 1.5rem;
  border-top: 1px solid #075B5A;
}

.footer-container {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-info h4 {
  color: #ffffff;
  font-size: 1.1rem;
  margin-bottom: 0.35rem;
}

.footer-info p {
  font-size: 0.85rem;
  opacity: 0.85;
}

.footer-copy {
  margin-top: 0.4rem;
  font-size: 0.75rem;
  color: #8EBFB9;
}

.footer-badges {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.footer-badges .tag {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
  color: #ffffff;
/* Wizard Preset Buttons */
.preset-btn {
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  font-size: 0.84rem;
  padding: 0.32rem 0.75rem;
  border-radius: var(--radius-full);
  background: #FFFFFF;
  border: 1px solid var(--primary-border);
  color: var(--primary);
  font-weight: 500;
  cursor: pointer;
}

.preset-btn:hover {
  background: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary-dark);
  transform: translateY(-1px);
}

.preset-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #FFFFFF;
  font-weight: 700;
  box-shadow: var(--shadow-sm);
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
  .site-header {
    padding: 1.75rem 1rem 1.5rem;
  }
  .header-title {
    font-size: 1.65rem;
  }
  .header-title span {
    display: block;
    margin-left: 0;
    font-size: 0.95rem;
  }
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  .term-quad-grid {
    grid-template-columns: 1fr;
  }
  .content-card {
    padding: 1rem;
  }
  .sim-canvas {
    height: 220px;
  }
}