/* ========================================
   TVIR Project Website - Main Stylesheet
   ======================================== */

/* CSS Variables */
:root {
  /* Colors */
  --primary-color: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --secondary-color: #7c3aed;
  --accent-color: #06b6d4;

  --text-primary: #1f2937;
  --text-secondary: #4b5563;
  --text-muted: #6b7280;
  --text-light: #9ca3af;

  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --bg-dark: #111827;

  --border-color: #e5e7eb;
  --border-light: #f3f4f6;

  --success-color: #10b981;
  --warning-color: #f59e0b;
  --error-color: #ef4444;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
  --gradient-hero: linear-gradient(
    135deg,
    #1e3a8a 0%,
    #312e81 50%,
    #1e1b4b 100%
  );
  --gradient-card: linear-gradient(145deg, #ffffff 0%, #f9fafb 100%);

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md:
    0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg:
    0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl:
    0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);

  /* Typography */
  --font-sans:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;

  /* Spacing */
  --section-padding: 6rem;
  --container-max: 1200px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-dark);
}

/* Container */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-light);
  transition: all var(--transition-base);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.nav-logo .logo-icon {
  font-size: 1.75rem;
}

.nav-logo .logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-menu a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 0;
  position: relative;
}

.nav-menu a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: width var(--transition-base);
}

.nav-menu a:hover {
  color: var(--primary-color);
}

.nav-menu a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--text-primary);
  cursor: pointer;
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 6rem 0 4rem;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: var(--gradient-hero);
  z-index: -2;
}

.hero-bg::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(
      circle at 20% 50%,
      rgba(59, 130, 246, 0.3) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 80% 20%,
      rgba(124, 58, 237, 0.3) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 40% 80%,
      rgba(6, 182, 212, 0.2) 0%,
      transparent 50%
    );
  z-index: -1;
}

.hero-content {
  text-align: center;
  color: white;
  max-width: 900px;
}

.venue-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.title-highlight {
  background: linear-gradient(135deg, #60a5fa 0%, #a78bfa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.title-gradient {
  background: linear-gradient(135deg, #93c5fd 0%, #c4b5fd 50%, #67e8f9 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.authors {
  margin-bottom: 2rem;
}

.author-list {
  font-size: 1.1rem;
  opacity: 0.9;
  margin-bottom: 0.5rem;
}

.affiliations {
  font-size: 0.95rem;
  opacity: 0.7;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 3rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all var(--transition-base);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: white;
  color: var(--primary-color);
  box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  color: var(--primary-dark);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.1);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.2);
  color: white;
  transform: translateY(-2px);
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 3rem;
  flex-wrap: wrap;
}

.stat-item {
  text-align: center;
}

.stat-number {
  display: block;
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, #60a5fa 0%, #a78bfa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 0.9rem;
  opacity: 0.8;
}

.scroll-indicator {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  animation: bounce 2s infinite;
  color: rgba(255, 255, 255, 0.6);
  font-size: 1.5rem;
}

@keyframes bounce {
  0%,
  20%,
  50%,
  80%,
  100% {
    transform: translateX(-50%) translateY(0);
  }
  40% {
    transform: translateX(-50%) translateY(-10px);
  }
  60% {
    transform: translateX(-50%) translateY(-5px);
  }
}

/* ========================================
   Sections
   ======================================== */
.section {
  padding: var(--section-padding) 0;
}

.section-alt {
  background: var(--bg-secondary);
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
}

.section-title i {
  color: var(--primary-color);
}

.section-subtitle {
  text-align: center;
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 800px;
  margin: 0 auto 3rem;
}

.subsection-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 3rem 0 1.5rem;
  color: var(--text-primary);
}

/* ========================================
   Abstract Section
   ======================================== */
.abstract-content {
  max-width: 900px;
  margin: 0 auto;
}

.abstract-content p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  text-align: justify;
}

.highlight-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.highlight-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2rem;
  text-align: center;
  transition: all var(--transition-base);
}

.highlight-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-light);
}

.card-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 1rem;
  background: var(--gradient-primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: white;
}

.highlight-card h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.highlight-card p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ========================================
   Motivation Section
   ======================================== */
.motivation-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.motivation-text h3 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.motivation-text p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.problem-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.problem-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: rgba(239, 68, 68, 0.1);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.95rem;
}

.problem-item i {
  color: var(--error-color);
}

.motivation-image {
  text-align: center;
}

.figure-img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  max-width: 100%;
  height: auto;
  margin: 0 auto;
}

/* 不同类型图片的尺寸控制 */
.motivation-image .figure-img {
  max-width: 550px;
}

.domain-image .figure-img {
  max-width: 600px;
}

.pipeline-image .figure-img,
.agent-architecture .figure-img {
  max-width: 900px;
}

.analysis-image .figure-img {
  max-width: 800px;
}

/* PDF Embed Styles */
.figure-pdf {
  width: 100%;
  height: 400px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  background: white;
}

.figure-pdf-wide {
  height: 500px;
}

.figure-pdf p {
  padding: 2rem;
  text-align: center;
  color: var(--text-muted);
}

.figure-pdf a {
  color: var(--primary-color);
  text-decoration: underline;
}

.figure-caption {
  margin-top: 1rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  text-align: center;
}

/* ========================================
   Benchmark Section
   ======================================== */
.domain-image,
.pipeline-image,
.analysis-image {
  text-align: center;
  margin: 2rem 0;
}

.principles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.principle-card {
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  text-align: center;
  transition: all var(--transition-base);
}

.principle-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary-light);
}

.principle-icon {
  width: 50px;
  height: 50px;
  margin: 0 auto 1rem;
  background: linear-gradient(135deg, #eff6ff 0%, #f5f3ff 100%);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: var(--primary-color);
}

.principle-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

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

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.stat-card {
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2rem;
  text-align: center;
  transition: all var(--transition-base);
}

.stat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.stat-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.stat-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* Evaluation Grid */
.eval-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 1.5rem;
}

.eval-card {
  background: white;
  border-radius: var(--radius-xl);
  padding: 2rem;
  box-shadow: var(--shadow-md);
}

.eval-card h4 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.eval-textual h4 {
  color: var(--primary-color);
}

.eval-visual h4 {
  color: var(--secondary-color);
}

.metric-list {
  list-style: none;
}

.metric-list li {
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border-light);
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.metric-list li:last-child {
  border-bottom: none;
}

.metric-list strong {
  color: var(--text-primary);
  font-weight: 600;
}

/* ========================================
   Agent Section
   ======================================== */
.agent-architecture {
  text-align: center;
  margin: 2rem 0 3rem;
}

.agent-components {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  max-width: 900px;
  margin: 0 auto;
}

.component-card {
  display: flex;
  gap: 1.5rem;
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 2rem;
  transition: all var(--transition-base);
}

.component-card:hover {
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.component-number {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: white;
}

.component-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.component-content h3 i {
  color: var(--primary-color);
}

.component-content p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.component-content ul {
  margin-top: 0.75rem;
  padding-left: 1.25rem;
}

.component-content li {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

/* ========================================
   Results Section
   ======================================== */
.results-table-container {
  margin: 2rem 0;
}

.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.results-table {
  width: 100%;
  border-collapse: collapse;
  background: white;
  font-size: 0.85rem;
}

.results-table th,
.results-table td {
  padding: 0.875rem 0.75rem;
  text-align: center;
  border-bottom: 1px solid var(--border-light);
}

.results-table th {
  background: var(--bg-tertiary);
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
}

.results-table th:first-child,
.results-table td:first-child {
  text-align: left;
  white-space: nowrap;
}

.results-table tbody tr:hover {
  background: var(--bg-secondary);
}

.results-table .highlight-row {
  background: linear-gradient(
    90deg,
    rgba(37, 99, 235, 0.05) 0%,
    rgba(124, 58, 237, 0.05) 100%
  );
}

.results-table .highlight-row:hover {
  background: linear-gradient(
    90deg,
    rgba(37, 99, 235, 0.1) 0%,
    rgba(124, 58, 237, 0.1) 100%
  );
}

.results-table .text-only {
  opacity: 0.7;
}

.results-table .best {
  font-weight: 700;
  color: var(--primary-color);
}

.table-note {
  margin-top: 1rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Key Insights */
.insights-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.insight-card {
  background: white;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 1.5rem;
  transition: all var(--transition-base);
}

.insight-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.insight-icon {
  width: 45px;
  height: 45px;
  background: linear-gradient(135deg, #eff6ff 0%, #f5f3ff 100%);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: var(--primary-color);
  margin-bottom: 1rem;
}

.insight-card h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.insight-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Ablation Table */
.ablation-table-wrapper {
  max-width: 600px;
  margin: 1.5rem auto;
  overflow-x: auto;
}

.ablation-table {
  width: 100%;
  border-collapse: collapse;
  background: white;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.ablation-table th,
.ablation-table td {
  padding: 1rem 1.25rem;
  text-align: center;
  border-bottom: 1px solid var(--border-light);
}

.ablation-table th {
  background: var(--bg-tertiary);
  font-weight: 600;
}

.ablation-table td:first-child {
  text-align: left;
}

.ablation-table .baseline {
  background: linear-gradient(
    90deg,
    rgba(37, 99, 235, 0.1) 0%,
    rgba(124, 58, 237, 0.1) 100%
  );
  font-weight: 600;
}

.ablation-table .significant {
  background: rgba(239, 68, 68, 0.05);
}

.delta {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.delta.negative {
  color: var(--error-color);
  font-weight: 600;
}

/* ========================================
   Citation Section
   ======================================== */
.citation-box {
  max-width: 800px;
  margin: 0 auto;
  background: var(--bg-dark);
  border-radius: var(--radius-xl);
  padding: 2rem;
  position: relative;
}

.citation-box pre {
  margin: 0;
  overflow-x: auto;
}

.citation-box code {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: #e5e7eb;
  line-height: 1.6;
}

.copy-btn {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: white;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

.copy-btn.copied {
  background: var(--success-color);
  border-color: var(--success-color);
}

/* ========================================
   Footer
   ======================================== */
.footer {
  background: var(--bg-dark);
  color: white;
  padding: 3rem 0 1.5rem;
}

.footer-content {
  text-align: center;
  margin-bottom: 2rem;
}

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.footer-logo .logo-img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.footer-text {
  color: var(--text-light);
  margin-bottom: 1.5rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
}

.footer-links a {
  width: 45px;
  height: 45px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
  transition: all var(--transition-fast);
}

.footer-links a:hover {
  background: var(--primary-color);
  transform: translateY(-3px);
}

.footer-bottom {
  text-align: center;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 0.25rem;
}

/* ========================================
   Back to Top Button
   ======================================== */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  background: var(--gradient-primary);
  border: none;
  border-radius: var(--radius-full);
  color: white;
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-lg);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-xl);
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1024px) {
  .motivation-content {
    grid-template-columns: 1fr;
  }

  .motivation-image {
    order: -1;
  }
}

@media (max-width: 768px) {
  :root {
    --section-padding: 4rem;
  }

  .nav-menu {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    padding: 1.5rem;
    gap: 0;
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
  }

  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-menu li {
    width: 100%;
  }

  .nav-menu a {
    display: block;
    padding: 1rem;
    border-bottom: 1px solid var(--border-light);
  }

  .nav-toggle {
    display: block;
  }

  .hero-title {
    font-size: 1.75rem;
  }

  .hero-stats {
    gap: 1.5rem;
  }

  .stat-number {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .component-card {
    flex-direction: column;
    text-align: center;
  }

  .component-number {
    margin: 0 auto;
  }

  .results-table {
    font-size: 0.75rem;
  }

  .results-table th,
  .results-table td {
    padding: 0.5rem 0.375rem;
  }
}

@media (max-width: 480px) {
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    max-width: 250px;
    justify-content: center;
  }

  .highlight-cards {
    grid-template-columns: 1fr;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .eval-grid {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   Utility Classes
   ======================================== */
.text-center {
  text-align: center;
}
.text-left {
  text-align: left;
}
.text-right {
  text-align: right;
}

.mt-1 {
  margin-top: 0.5rem;
}
.mt-2 {
  margin-top: 1rem;
}
.mt-3 {
  margin-top: 1.5rem;
}
.mt-4 {
  margin-top: 2rem;
}

.mb-1 {
  margin-bottom: 0.5rem;
}
.mb-2 {
  margin-bottom: 1rem;
}
.mb-3 {
  margin-bottom: 1.5rem;
}
.mb-4 {
  margin-bottom: 2rem;
}

.hidden {
  display: none;
}
.visible {
  display: block;
}