@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800;900&family=Plus+Jakarta+Sans:wght@400;500;600;700&display=swap');

:root {
  --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;

  --bg-main: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --bg-muted: #f1f5f9;
  --bg-subtle: #e2e8f0;

  --text-main: #0f172a;
  --text-muted: #475569;
  --text-dim: #64748b;

  /* Modern Indigo & Coral Theme */
  --asl-primary: #4f46e5;
  --asl-bg: #eef2ff;
  --asl-text: #4338ca;

  --isl-primary: #0d9488;
  --isl-bg: #ccfbf1;
  --isl-text: #0f766e;

  --accent-warm: #ea580c;
  --accent-warm-bg: #ffedd5;
  --accent-warm-text: #c2410c;

  --accent-pink: #f43f5e;
  --accent-pink-bg: #ffe4e6;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --transition: all 0.2s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  box-shadow: none !important;
}

.material-symbols-rounded {
  font-family: 'Material Symbols Rounded';
  font-weight: normal;
  font-style: normal;
  font-size: 20px;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-transform: none;
  letter-spacing: normal;
  word-wrap: normal;
  white-space: nowrap;
  direction: ltr;
  vertical-align: middle;
  font-feature-settings: 'liga';
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-main);
  color: var(--text-main);
  min-height: 100vh;
  line-height: 1.6;
  overflow-x: hidden;
}

/* App Container */
.app-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px 80px 24px;
}

/* Navbar */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 0;
  position: sticky;
  top: 0;
  background: var(--bg-main);
  z-index: 100;
  margin-bottom: 24px;
}

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

.brand-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  background: var(--asl-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-weight: 800;
  font-size: 22px;
}

.brand-text h1 {
  font-family: var(--font-heading);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.5px;
  color: #0f172a;
}

.brand-text p {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.nav-links {
  display: flex;
  gap: 6px;
  background: var(--bg-muted);
  padding: 4px;
  border-radius: var(--radius-full);
}

.nav-tab {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 600;
  color: var(--text-muted);
  border: none;
  background: transparent;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-tab:hover {
  color: var(--text-main);
}

.nav-tab.active {
  background: var(--asl-primary);
  color: #ffffff;
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.btn-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: var(--bg-muted);
  border: none;
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
}

.btn-icon:hover {
  background: var(--bg-subtle);
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 32px 20px 40px;
}

.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: var(--asl-bg);
  color: var(--asl-text);
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 18px;
  border: none;
}

.hero h2 {
  font-family: var(--font-heading);
  font-size: clamp(32px, 5vw, 50px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -1px;
  margin-bottom: 16px;
  color: #0f172a;
}

.hero h2 .highlight-asl {
  color: var(--asl-primary);
}

.hero h2 .highlight-isl {
  color: var(--isl-primary);
}

.hero-sub {
  font-size: clamp(16px, 2vw, 18px);
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto 28px;
}

/* Mode Switcher Buttons */
.mode-toggle-card {
  display: inline-flex;
  background: var(--bg-muted);
  padding: 6px;
  border-radius: var(--radius-full);
  margin-bottom: 30px;
  border: none;
}

.mode-btn {
  padding: 10px 24px;
  border-radius: var(--radius-full);
  border: none;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  background: transparent;
}

.mode-btn .hand-count {
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.06);
  color: var(--text-muted);
}

.mode-btn[data-mode="ASL"].active {
  background: var(--asl-primary);
  color: #ffffff;
}

.mode-btn[data-mode="ASL"].active .hand-count {
  background: rgba(255, 255, 255, 0.25);
  color: #ffffff;
}

.mode-btn[data-mode="ISL"].active {
  background: var(--isl-primary);
  color: #ffffff;
}

.mode-btn[data-mode="ISL"].active .hand-count {
  background: rgba(255, 255, 255, 0.25);
  color: #ffffff;
}

.mode-btn[data-mode="COMPARE"].active {
  background: #7c3aed;
  color: #ffffff;
}

/* Info Callout Box */
.info-callout {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  margin: 0 auto 30px;
  max-width: 820px;
  text-align: left;
  border: none;
}

.callout-asl {
  background: var(--asl-bg);
  color: var(--asl-text);
}

.callout-isl {
  background: var(--isl-bg);
  color: var(--isl-text);
}

.callout-icon {
  font-size: 28px;
  flex-shrink: 0;
}

.callout-text h4 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 2px;
  color: #0f172a;
}

.callout-text p {
  font-size: 13px;
  color: var(--text-muted);
}

/* Search and Filter Bar */
.filter-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 28px;
  padding: 14px 18px;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border: none;
}

.search-box {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--bg-muted);
  padding: 8px 16px;
  border-radius: var(--radius-full);
  min-width: 260px;
  flex: 1;
  max-width: 400px;
  border: none;
}

.search-box input {
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-main);
  font-size: 14px;
  width: 100%;
}

.search-box input::placeholder {
  color: var(--text-dim);
}

.category-pills {
  display: flex;
  gap: 8px;
  overflow-x: auto;
}

.cat-pill {
  padding: 6px 16px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 600;
  border: none;
  background: var(--bg-muted);
  color: var(--text-muted);
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.cat-pill:hover {
  background: var(--bg-subtle);
  color: var(--text-main);
}

.cat-pill.active {
  background: var(--asl-primary);
  color: #ffffff;
  font-weight: 700;
}

/* Cards Grid */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 20px;
  margin-bottom: 60px;
}

.sign-card {
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  cursor: pointer;
  transition: var(--transition);
}

.sign-card:hover {
  background: var(--bg-card-hover);
}

.sign-card .card-badge {
  position: absolute;
  top: 14px;
  left: 14px;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  border: none;
}

.card-badge.asl {
  background: var(--asl-bg);
  color: var(--asl-text);
}

.card-badge.isl {
  background: var(--isl-bg);
  color: var(--isl-text);
}

.card-actions-top {
  position: absolute;
  top: 12px;
  right: 12px;
  display: flex;
  gap: 6px;
}

.card-action-btn {
  background: var(--bg-muted);
  border: none;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  color: var(--text-dim);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.card-action-btn:hover {
  color: var(--text-main);
  background: var(--bg-subtle);
}

.card-action-btn.active {
  color: var(--accent-warm);
  background: var(--accent-warm-bg);
}

.card-action-btn.mastered-btn.active {
  color: var(--isl-primary);
  background: var(--isl-bg);
}

.card-visual {
  margin: 16px 0 12px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.card-visual svg,
.card-visual img {
  max-width: 100%;
  height: auto;
  display: block;
}

.sign-img-container {
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: none;
  border-radius: 0;
  overflow: visible;
}

.sign-img-container img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  border: none;
  border-radius: 0;
  mix-blend-mode: multiply;
}

.card-title-row {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 6px;
}

.letter-heading {
  font-family: var(--font-heading);
  font-size: 28px;
  font-weight: 800;
  color: #0f172a;
}

.card-meta {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 600;
}

.badge-vowel {
  font-size: 10px;
  font-weight: 800;
  padding: 2px 7px;
  border-radius: var(--radius-full);
  background: var(--accent-warm-bg);
  color: var(--accent-warm-text);
  letter-spacing: 0.5px;
}

.card-desc {
  font-size: 13px;
  color: var(--text-muted);
  text-align: center;
  line-height: 1.45;
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-footer {
  width: 100%;
  padding-top: 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  background: var(--bg-muted);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  border: none;
}

.inspect-hint {
  color: var(--asl-primary);
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Side-by-Side Comparison Card */
.comparison-card {
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-md);
  padding: 24px;
}

.comp-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
  padding-bottom: 12px;
}

.comp-letter {
  font-size: 34px;
  font-weight: 900;
  font-family: var(--font-heading);
  color: #0f172a;
}

.comp-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.comp-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 16px;
  border-radius: var(--radius-sm);
  border: none;
}

.comp-col.asl {
  background: var(--asl-bg);
}

.comp-col.isl {
  background: var(--isl-bg);
}

.comp-tag {
  font-size: 11px;
  font-weight: 800;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  margin-bottom: 8px;
  border: none;
}

.comp-col.asl .comp-tag {
  background: #bae6fd;
  color: #0369a1;
}

.comp-col.isl .comp-tag {
  background: #a7f3d0;
  color: #047857;
}

.comp-desc {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 8px;
  line-height: 1.4;
}

/* Practice Mirror Section */
.mirror-section {
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-lg);
  padding: 32px;
  margin: 20px 0 60px;
}

.mirror-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 24px;
}

.mirror-title {
  display: flex;
  align-items: center;
  gap: 12px;
}

.mirror-title h3 {
  font-size: 24px;
  font-weight: 800;
  font-family: var(--font-heading);
  color: #0f172a;
}

.mirror-studio-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

@media (max-width: 840px) {
  .mirror-studio-grid {
    grid-template-columns: 1fr;
  }
}

.camera-box {
  position: relative;
  background: #1e293b;
  border-radius: var(--radius-md);
  overflow: hidden;
  aspect-ratio: 4/3;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
}

.camera-box video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scaleX(-1);
}

.camera-box video.unmirrored {
  transform: scaleX(1);
}

.camera-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 24px;
  color: #94a3b8;
}

.camera-placeholder svg {
  margin-bottom: 14px;
  color: #cbd5e1;
}

.reference-card-box {
  background: var(--bg-main);
  border: none;
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.ref-selector-bar {
  display: flex;
  gap: 8px;
  align-items: center;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.ref-selector-bar select {
  background: var(--bg-secondary);
  color: var(--text-main);
  border: none;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 14px;
  outline: none;
}

.ref-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.ref-instructions {
  margin-top: 16px;
  font-size: 13px;
  color: var(--text-muted);
  text-align: left;
  line-height: 1.5;
  background: var(--bg-secondary);
  padding: 14px 18px;
  border-radius: var(--radius-sm);
  border: none;
  width: 100%;
}

/* Fingerspelling Tool */
.fingerspell-tool {
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-bottom: 60px;
}

.fingerspell-tool h3 {
  font-size: 24px;
  font-weight: 800;
  font-family: var(--font-heading);
  margin-bottom: 8px;
  color: #0f172a;
}

.fingerspell-input-row {
  display: flex;
  gap: 12px;
  margin: 20px 0 28px;
  max-width: 600px;
}

.fingerspell-input-row input {
  flex: 1;
  background: var(--bg-muted);
  border: none;
  padding: 14px 20px;
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 16px;
  font-weight: 600;
  outline: none;
}

.spelled-stream {
  display: flex;
  gap: 16px;
  overflow-x: auto;
  padding: 16px 4px 24px;
}

.spelled-letter-card {
  min-width: 130px;
  background: var(--bg-main);
  border: none;
  border-radius: var(--radius-md);
  padding: 14px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.spelled-letter-card .letter-label {
  font-size: 22px;
  font-weight: 900;
  color: var(--asl-primary);
  margin-top: 6px;
}

/* Quiz Arena */
.quiz-section {
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-lg);
  padding: 36px;
  margin-bottom: 60px;
}

.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 28px;
  flex-wrap: wrap;
  gap: 16px;
}

.quiz-score-pill {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--accent-warm-bg);
  border: none;
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-weight: 700;
  color: var(--accent-warm-text);
}

.quiz-box {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: center;
}

@media (max-width: 768px) {
  .quiz-box {
    grid-template-columns: 1fr;
  }
}

.quiz-question-visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: var(--bg-main);
  border-radius: var(--radius-md);
  border: none;
}

.quiz-options-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.quiz-option-btn {
  padding: 16px 20px;
  background: var(--bg-main);
  border: none;
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-size: 16px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.quiz-option-btn:hover {
  background: var(--bg-subtle);
}

.quiz-option-btn.correct {
  background: #d1fae5 !important;
  color: #047857 !important;
}

.quiz-option-btn.wrong {
  background: #fee2e2 !important;
  color: #b91c1c !important;
}

/* Modal Popup */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.4);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-card {
  background: #ffffff;
  border: none;
  border-radius: var(--radius-lg);
  max-width: 640px;
  width: 100%;
  padding: 32px;
  position: relative;
  max-height: 90vh;
  overflow-y: auto;
}

.modal-close-btn {
  position: absolute;
  top: 20px;
  right: 20px;
  background: var(--bg-muted);
  border: none;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-close-btn:hover {
  background: var(--bg-subtle);
  color: var(--text-main);
}

.modal-visual-area {
  display: flex;
  justify-content: center;
  margin: 16px 0 24px;
}

.modal-steps-list {
  margin: 16px 0;
  padding-left: 20px;
  color: var(--text-muted);
}

.modal-steps-list li {
  margin-bottom: 8px;
  line-height: 1.5;
}

.mnemonic-box {
  background: var(--accent-warm-bg);
  border: none;
  padding: 14px 18px;
  border-radius: var(--radius-sm);
  margin-top: 16px;
  font-size: 13px;
  color: #92400e;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

/* Primary Button Styles */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  background: var(--asl-primary);
  color: #ffffff;
  font-weight: 700;
  font-size: 14px;
  border: none;
  cursor: pointer;
  transition: var(--transition);
}

.btn-primary:hover {
  background: var(--asl-text);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  background: var(--bg-muted);
  border: none;
  color: var(--text-main);
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary:hover {
  background: var(--bg-subtle);
}

/* Tab View Visibility */
.tab-view {
  display: none;
}

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

/* SEO Educational Guide Section */
.seo-knowledge-section {
  margin: 60px 0 30px;
  padding: 36px 30px;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
}

.seo-knowledge-section h2 {
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--text-main);
}

.seo-knowledge-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-top: 20px;
}

.seo-card {
  background: var(--bg-main);
  padding: 20px;
  border-radius: var(--radius-md);
}

.seo-card h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
  color: #0f172a;
}

.seo-card p, .seo-card li {
  font-size: 13.5px;
  color: var(--text-muted);
  line-height: 1.5;
}

.seo-card ul {
  padding-left: 18px;
  margin-top: 8px;
}

/* Footer */
.footer {
  text-align: center;
  padding: 40px 0 20px;
  color: var(--text-dim);
  font-size: 13px;
}

/* ============================================================
   RESPONSIVE DESIGN (TABLETS, MOBILES, AND COMPACT SCREENS)
   ============================================================ */

/* Medium Screens & Tablets (<= 960px) */
@media (max-width: 960px) {
  .navbar {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    padding: 14px 0;
  }

  .brand {
    justify-content: center;
  }

  .nav-links {
    width: 100%;
    display: flex;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding: 4px;
    justify-content: flex-start;
    scrollbar-width: none;
  }

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

  .nav-tab {
    flex-shrink: 0;
    padding: 8px 14px;
    font-size: 13px;
    white-space: nowrap;
  }

  .filter-bar {
    flex-direction: column;
    align-items: stretch;
    gap: 12px;
    padding: 12px 14px;
  }

  .search-box {
    min-width: 100%;
    max-width: 100%;
    width: 100%;
  }

  .category-pills {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

  .category-pills::-webkit-scrollbar {
    display: none;
  }

  .cards-grid {
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 16px;
  }
}

/* Tablets & Mobile Landscape (<= 768px) */
@media (max-width: 768px) {
  .app-container {
    padding: 0 16px 60px 16px;
  }

  .hero {
    padding: 10px 0 24px;
  }

  .hero h2 {
    font-size: clamp(26px, 6vw, 34px);
    letter-spacing: -0.5px;
    margin-bottom: 12px;
  }

  .hero-sub {
    font-size: 14.5px;
    line-height: 1.5;
    margin-bottom: 20px;
  }

  .mode-toggle-card {
    width: 100%;
    max-width: 480px;
    display: flex;
    padding: 4px;
    margin: 0 auto 20px;
    border-radius: var(--radius-md);
    gap: 4px;
  }

  .mode-btn {
    flex: 1;
    justify-content: center;
    padding: 8px 10px;
    font-size: 13px;
    border-radius: var(--radius-sm);
    gap: 6px;
  }

  .mode-btn .hand-count {
    display: none;
  }

  .info-callout {
    padding: 12px 14px;
    gap: 12px;
    margin-bottom: 20px;
  }

  .callout-icon {
    font-size: 24px;
  }

  .callout-text h4 {
    font-size: 14px;
  }

  .callout-text p {
    font-size: 12.5px;
  }

  /* Mirror View */
  .mirror-section {
    padding: 20px 16px;
    margin: 10px 0 40px;
    border-radius: var(--radius-md);
  }

  .mirror-header {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    margin-bottom: 18px;
  }

  .mirror-header > div:last-child {
    display: flex;
    gap: 8px;
    width: 100%;
  }

  .mirror-header .btn-primary,
  .mirror-header .btn-secondary {
    flex: 1;
    justify-content: center;
    padding: 9px 12px;
    font-size: 13px;
  }

  .mirror-studio-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .reference-card-box {
    padding: 16px;
  }

  .ref-selector-bar {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

  .ref-selector-bar select {
    width: 100%;
    margin-left: 0 !important;
  }

  /* Fingerspeller Tool */
  .fingerspell-tool {
    padding: 20px 16px;
    border-radius: var(--radius-md);
    margin-bottom: 40px;
  }

  .fingerspell-input-row {
    flex-direction: column;
    gap: 10px;
    max-width: 100%;
    margin: 16px 0 20px;
  }

  .fingerspell-input-row input {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
  }

  .fingerspell-input-row .mode-toggle-card {
    width: 100%;
    margin: 0;
  }

  .spelled-stream {
    padding: 10px 0 16px;
  }

  .spelled-letter-card {
    min-width: 105px;
    padding: 10px;
  }

  /* Quiz View */
  .quiz-section {
    padding: 20px 16px;
    border-radius: var(--radius-md);
    margin-bottom: 40px;
  }

  .quiz-header {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    margin-bottom: 18px;
  }

  .quiz-header > div:last-child {
    display: flex;
    justify-content: space-between;
    width: 100%;
    align-items: center;
  }

  .quiz-box {
    grid-template-columns: 1fr;
    gap: 18px;
  }

  .quiz-question-visual {
    padding: 16px;
  }

  .quiz-option-btn {
    padding: 12px 14px;
    font-size: 14.5px;
  }

  /* Comparison View */
  .comparison-card {
    padding: 16px;
  }

  .comp-columns {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* SEO Section */
  .seo-knowledge-section {
    padding: 24px 18px;
    margin: 40px 0 20px;
  }

  .seo-knowledge-section h2 {
    font-size: 20px;
  }

  .seo-knowledge-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* Modal Dialog */
  .modal-card {
    padding: 24px 18px;
    margin: 12px;
    max-height: 92vh;
    border-radius: var(--radius-md);
  }

  .modal-card h2 {
    font-size: 24px !important;
  }

  .modal-close-btn {
    top: 14px;
    right: 14px;
    width: 32px;
    height: 32px;
  }
}

/* Mobile Screens (<= 520px) */
@media (max-width: 520px) {
  .app-container {
    padding: 0 12px 50px 12px;
  }

  .brand-text h1 {
    font-size: 19px;
  }

  .brand-icon {
    width: 38px;
    height: 38px;
    font-size: 18px;
  }

  .nav-tab {
    padding: 7px 11px;
    font-size: 12.5px;
    gap: 5px;
  }

  .nav-tab .material-symbols-rounded {
    font-size: 17px;
  }

  /* 2-Column Mobile Grid for Sign Cards */
  .cards-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    margin-bottom: 40px;
  }

  /* Daily Phrases should stay 1 column for readability */
  #phrases-container.cards-grid {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .sign-card {
    padding: 12px 8px 10px;
    border-radius: var(--radius-sm);
  }

  .sign-card .card-badge {
    top: 6px;
    left: 6px;
    font-size: 9.5px;
    padding: 1px 6px;
  }

  .card-actions-top {
    top: 6px;
    right: 6px;
    gap: 2px;
  }

  .card-action-btn {
    width: 26px;
    height: 26px;
  }

  .card-action-btn .material-symbols-rounded {
    font-size: 14px !important;
  }

  .card-visual {
    margin: 10px 0 4px;
  }

  .card-visual .sign-img-container {
    width: 105px !important;
    height: 105px !important;
  }

  .card-visual .sign-svg {
    width: 105px !important;
    height: 105px !important;
  }

  .card-title-row {
    margin-bottom: 2px;
    gap: 4px;
  }

  .letter-heading {
    font-size: 20px;
  }

  .badge-vowel {
    font-size: 9px;
    padding: 1px 5px;
  }

  .card-meta {
    font-size: 10.5px;
  }

  .card-desc,
  .card-summary {
    font-size: 11px;
    line-height: 1.35;
    margin-bottom: 6px;
    -webkit-line-clamp: 2;
  }

  .card-footer {
    padding: 5px 6px;
    font-size: 10.5px;
  }

  .inspect-hint {
    font-size: 10px;
    gap: 2px;
  }

  /* Phrases action split on very small screens */
  .sign-card > div[style*="grid-template-columns: 1fr 1fr"] {
    grid-template-columns: 1fr !important;
    gap: 8px !important;
  }

  #phrases-container .sign-card {
    padding: 16px 14px;
  }

  #phrases-container .card-visual .sign-svg {
    width: 130px !important;
    height: 130px !important;
  }
}