/* Enhanced Base Styles for Academic Research */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --secondary: #0284c7;
  --accent: #f97316;
  --success: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
  --light: #f8fafc;
  --light-gray: #f1f5f9;
  --dark: #0f172a;
  --gray: #64748b;
  --text: #334155;
  --text-light: #64748b;
  --border: #e2e8f0;
  --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1),
    0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1),
    0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --border-radius: 12px;
  --border-radius-lg: 16px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Inter", "Poppins", -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.7;
  color: var(--text);
  background-color: #ffffff;
  overflow-x: hidden;
  font-weight: 400;
  letter-spacing: -0.01em;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  color: var(--dark);
  line-height: 1.3;
  margin-bottom: 1rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 3.5rem;
  font-weight: 800;
}
h2 {
  font-size: 2.5rem;
  font-weight: 700;
}
h3 {
  font-size: 1.875rem;
  font-weight: 600;
}
h4 {
  font-size: 1.5rem;
  font-weight: 600;
}
h5 {
  font-size: 1.25rem;
  font-weight: 600;
}

p {
  margin-bottom: 1rem;
  color: var(--text);
  line-height: 1.75;
}

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

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

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

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Enhanced Preloader */
.preloader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #ffffff 0%, var(--light) 100%);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity 0.5s, visibility 0.5s;
}

.loader {
  width: 60px;
  height: 60px;
  border: 4px solid var(--light-gray);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.preloader.hidden {
  opacity: 0;
  visibility: hidden;
}

/* Enhanced Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 20px 0;
  transition: var(--transition);
}

.header.scrolled {
  padding: 16px 0;
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: -0.02em;
}

.logo i {
  margin-right: 12px;
  color: var(--primary);
  font-size: 1.75rem;
}

.menu-toggle {
  display: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--dark);
  padding: 8px;
  border-radius: 8px;
  transition: var(--transition);
}

.menu-toggle:hover {
  background-color: var(--light);
}

.navbar {
  display: flex;
  align-items: center;
}

.tabs {
  display: flex;
  list-style: none;
  gap: 8px;
}

.tabs li {
  position: relative;
}

.tabs a {
  color: var(--text);
  font-weight: 500;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  position: relative;
  border-radius: 8px;
  transition: var(--transition);
  font-size: 0.95rem;
}

.tabs a i {
  margin-right: 8px;
  font-size: 0.9rem;
}

.tabs a:hover {
  color: var(--primary);
  background-color: rgba(37, 99, 235, 0.05);
}

.tabs li.active a {
  color: var(--primary);
  background-color: rgba(37, 99, 235, 0.1);
  font-weight: 600;
}

/* Enhanced Hero Section */
.hero-section {
  padding: 180px 0 120px;
  background: linear-gradient(
    135deg,
    rgba(37, 99, 235, 0.03) 0%,
    rgba(2, 132, 199, 0.05) 100%
  );
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: "";
  position: absolute;
  right: -10%;
  top: -15%;
  width: 400px;
  height: 400px;
  background: radial-gradient(
    circle,
    rgba(37, 99, 235, 0.08) 0%,
    transparent 70%
  );
  border-radius: 50%;
}

.hero-section::after {
  content: "";
  position: absolute;
  left: -10%;
  bottom: -15%;
  width: 350px;
  height: 350px;
  background: radial-gradient(
    circle,
    rgba(2, 132, 199, 0.06) 0%,
    transparent 70%
  );
  border-radius: 50%;
}

.hero-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 60px;
  position: relative;
  z-index: 2;
}

.hero-text {
  flex: 1;
  max-width: 600px;
}

.hero-text h1 {
  font-size: 3.75rem;
  font-weight: 800;
  margin-bottom: 24px;
  line-height: 1.1;
  color: var(--dark);
  letter-spacing: -0.03em;
}

.hero-text h1 span {
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 1.5rem;
  color: var(--text-light);
  margin-bottom: 28px;
  font-weight: 500;
  letter-spacing: -0.01em;
}

.hero-text p {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--text);
  margin-bottom: 20px;
}

.hero-image {
  flex: 1;
  position: relative;
  max-width: 500px;
}

.hero-image img {
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  transform: perspective(1000px) rotateY(-3deg) rotateX(2deg);
  transition: transform 0.6s ease;
}

.hero-image:hover img {
  transform: perspective(1000px) rotateY(0) rotateX(0);
}

/* Enhanced Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 1rem;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  outline: none;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.primary-btn {
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: white;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.primary-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
  color: white;
}

.primary-btn i {
  margin-left: 8px;
  transition: var(--transition);
}

.primary-btn:hover i {
  transform: translateX(4px);
}

/* Enhanced Section Styles */
section {
  padding: 120px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 80px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.section-header h2 {
  font-size: 2.75rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.section-header p {
  font-size: 1.25rem;
  color: var(--text-light);
  margin-bottom: 0;
  line-height: 1.6;
}

.underline {
  height: 4px;
  width: 80px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  margin: 0 auto 24px;
  border-radius: 2px;
}

/* Enhanced About Section */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  margin-bottom: 100px;
  align-items: center;
}

.about-text {
  font-size: 1.125rem;
  line-height: 1.8;
}

.about-text h3 {
  color: var(--primary);
  margin-top: 40px;
  margin-bottom: 20px;
  font-size: 1.5rem;
  font-weight: 600;
}

.about-text p {
  margin-bottom: 24px;
}

.feature-boxes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  margin-top: 60px;
}

.feature-box {
  background: white;
  border-radius: var(--border-radius);
  padding: 40px 32px;
  text-align: center;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.feature-box:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(37, 99, 235, 0.2);
}

.feature-box i {
  font-size: 2.5rem;
  color: var(--primary);
  margin-bottom: 24px;
  display: block;
}

.feature-box h4 {
  font-size: 1.25rem;
  margin-bottom: 16px;
  color: var(--dark);
}

.feature-box p {
  color: var(--text-light);
  margin-bottom: 0;
  line-height: 1.6;
}

.about-image img {
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
}

.about-image:hover img {
  transform: translateY(-8px);
  box-shadow: 0 25px 50px rgba(0, 0, 0, 0.15);
}

/* Enhanced Process Flow */
.process-flow {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
  margin-top: 80px;
}

.process-step {
  position: relative;
  background: white;
  border-radius: var(--border-radius);
  padding: 40px 32px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.process-step:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.step-number {
  position: absolute;
  top: -20px;
  left: 32px;
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: white;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: 700;
  font-size: 1.125rem;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.step-content {
  text-align: center;
  padding-top: 16px;
}

.step-content i {
  font-size: 3rem;
  color: var(--primary);
  margin-bottom: 24px;
  display: block;
}

.step-content h4 {
  font-size: 1.375rem;
  margin-bottom: 16px;
  color: var(--dark);
}

.step-content p {
  color: var(--text-light);
  margin-bottom: 0;
  line-height: 1.6;
}

/* Enhanced Statistics Section */
#statistics {
  background: linear-gradient(135deg, var(--light) 0%, white 100%);
  padding: 120px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  margin-bottom: 80px;
}

.stat-card {
  background: white;
  border-radius: var(--border-radius);
  padding: 40px 32px;
  text-align: center;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.stat-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(37, 99, 235, 0.2);
}

.stat-card i {
  font-size: 3rem;
  margin-bottom: 24px;
  color: var(--primary);
  display: block;
}

.stat-card h3 {
  color: var(--dark);
  font-size: 1.25rem;
  margin-bottom: 16px;
  font-weight: 600;
}

.stat-number {
  font-size: 3rem;
  font-weight: 800;
  color: var(--primary);
  line-height: 1;
}

/* Enhanced Charts */
.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
  gap: 32px;
  margin-top: 40px;
}

.chart-container {
  background: white;
  border-radius: var(--border-radius);
  padding: 24px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.chart-container:hover {
  box-shadow: var(--shadow-lg);
}

/* Enhanced Prediction Section */
#prediction {
  background: var(--light);
}

.prediction-content {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 40px;
  margin-top: 40px;
}

.form-card,
.result-card {
  background: white;
  border-radius: var(--border-radius);
  padding: 40px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
}

.form-card h3,
.result-card h4 {
  font-size: 1.5rem;
  margin-bottom: 32px;
  color: var(--dark);
  display: flex;
  align-items: center;
  font-weight: 600;
}

.form-card h3 i,
.result-card h4 i {
  margin-right: 12px;
  color: var(--primary);
  font-size: 1.25rem;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 24px;
}

.form-label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--dark);
  font-size: 0.95rem;
}

.form-label i {
  margin-right: 8px;
  color: var(--primary);
  font-size: 0.9rem;
}

.form-select {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background-color: white;
  color: var(--text);
  font-size: 1rem;
  transition: var(--transition);
  font-family: inherit;
}

.form-select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  outline: none;
}

.btn-predict {
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  color: white;
  border: none;
  padding: 16px 32px;
  border-radius: 50px;
  font-size: 1.125rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  margin-top: 32px;
}

.btn-predict i {
  margin-right: 12px;
}

.btn-predict:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
}

/* Excel Analysis Section Styles */
.excel-analysis-section {
  margin-top: 80px;
  padding-top: 80px;
  border-top: 2px solid var(--border);
}

.excel-card {
  background: linear-gradient(135deg, #f8fafc 0%, white 100%);
  border-radius: var(--border-radius-lg);
  padding: 48px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  text-align: center;
  transition: var(--transition);
  margin-bottom: 32px;
}

.excel-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.excel-content {
  max-width: 600px;
  margin: 0 auto;
}

.excel-icon {
  margin-bottom: 32px;
}

.excel-icon i {
  font-size: 4rem;
  color: var(--primary);
  background: rgba(37, 99, 235, 0.1);
  padding: 32px;
  border-radius: 50%;
  display: inline-block;
}

.excel-card h4 {
  font-size: 1.875rem;
  margin-bottom: 20px;
  color: var(--dark);
  font-weight: 600;
}

.excel-card p {
  font-size: 1.125rem;
  color: var(--text-light);
  margin-bottom: 32px;
  line-height: 1.7;
}

.excel-btn {
  background: linear-gradient(135deg, #059669 0%, #10b981 100%);
  color: white;
  padding: 16px 40px;
  border-radius: 50px;
  font-size: 1.125rem;
  font-weight: 600;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  transition: var(--transition);
  box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
  margin-bottom: 32px;
}

.excel-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(16, 185, 129, 0.4);
  color: white;
}

.excel-btn i {
  margin-right: 12px;
  font-size: 1rem;
}

.excel-features {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 32px;
  text-align: left;
}

.feature-item {
  display: flex;
  align-items: center;
  padding: 12px 0;
}

.feature-item i {
  color: var(--success);
  margin-right: 12px;
  font-size: 1.125rem;
}

.feature-item span {
  color: var(--text);
  font-size: 1rem;
  font-weight: 500;
}

.server-notice {
  background: linear-gradient(
    135deg,
    rgba(249, 115, 22, 0.05) 0%,
    rgba(245, 158, 11, 0.05) 100%
  );
  border: 1px solid rgba(249, 115, 22, 0.2);
  border-radius: var(--border-radius);
  padding: 24px;
}

.notice-content {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.notice-content i {
  color: var(--warning);
  font-size: 1.25rem;
  margin-top: 2px;
  flex-shrink: 0;
}

.notice-text {
  color: var(--text);
  line-height: 1.6;
}

.notice-text strong {
  color: var(--dark);
  font-weight: 600;
}

/* Enhanced Result Styles */
.loading-spinner {
  display: none;
  text-align: center;
  padding: 40px;
}

.prediction-result {
  margin-bottom: 32px;
}

.prediction-result h5 {
  font-size: 1.125rem;
  margin-bottom: 12px;
  color: var(--dark);
  font-weight: 600;
}

.alert {
  padding: 16px 20px;
  border-radius: 8px;
  font-weight: 500;
  font-size: 1rem;
}

.alert-success {
  background-color: rgba(16, 185, 129, 0.1);
  color: var(--success);
  border-left: 4px solid var(--success);
}

.alert-danger {
  background-color: rgba(239, 68, 68, 0.1);
  color: var(--danger);
  border-left: 4px solid var(--danger);
}

.prediction-percentages h5 {
  font-size: 1.125rem;
  margin-bottom: 12px;
  color: var(--dark);
  font-weight: 600;
}

.progress {
  height: 28px;
  background-color: var(--light-gray);
  border-radius: 50px;
  margin-bottom: 24px;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 600;
  font-size: 0.9rem;
  transition: width 1s ease;
}

.bg-success {
  background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
}

.bg-danger {
  background: linear-gradient(135deg, var(--danger) 0%, #dc2626 100%);
}

/* .chart-container already styled for Plotly charts, ensure it works for Chart.js too */
.chart-container#predictionChartContainer {
  /* If specific styling needed for this one */
  margin-top: 32px;
  height: 280px; /* Or as needed */
}

.card {
  /* This is for the "Model Information" card */
  background: white;
  border-radius: var(--border-radius);
  padding: 24px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
  border: 1px solid var(--border);
  margin-top: 32px;
}

.card-title {
  font-size: 1.125rem;
  margin-bottom: 20px;
  color: var(--dark);
  display: flex;
  align-items: center;
  font-weight: 600;
}

.card-title i {
  margin-right: 12px;
  color: var(--primary);
}

.d-flex {
  /* Utility for flex items in card */
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.badge {
  padding: 6px 12px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 0.875rem;
}

.bg-primary {
  /* Bootstrap class, ensure it uses your var */
  background-color: var(
    --primary
  ) !important; /* important if Bootstrap is also loaded */
  color: white;
}

.bg-info {
  /* Bootstrap class */
  background-color: var(--secondary) !important;
  color: white;
}

/* Enhanced Team Section */
#team {
  padding: 120px 0;
  background: var(--light);
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 48px;
  max-width: 1000px;
  margin: 0 auto;
}

.team-member {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  background: white;
  padding: 48px 32px;
  border-radius: var(--border-radius-lg);
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.team-member:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.team-member img {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 24px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
  border: 4px solid white;
}

.team-member h3 {
  font-size: 1.5rem;
  color: var(--dark);
  margin-bottom: 8px;
  font-weight: 600;
}

.position {
  color: var(--primary);
  margin-bottom: 16px;
  font-weight: 500;
  font-size: 1rem;
}

.member-description {
  color: var(--text-light);
  margin-bottom: 24px;
  line-height: 1.6;
  font-size: 0.95rem;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 16px;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background-color: var(--light);
  color: var(--primary);
  border-radius: 50%;
  transition: var(--transition);
  border: 1px solid var(--border);
}

.social-links a:hover {
  background-color: var(--primary);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

/* Enhanced Contact Section */
.contact-grid {
  display: grid;
  grid-template-columns: 3fr 2fr;
  gap: 60px;
}

.contact-form {
  background: white;
  border-radius: var(--border-radius);
  padding: 40px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.contact-form h3 {
  font-size: 1.75rem;
  margin-bottom: 32px;
  color: var(--dark);
  display: flex;
  align-items: center;
}

.contact-form h3 i {
  margin-right: 16px;
  color: var(--primary);
}

.contact-form .form-group {
  margin-bottom: 24px;
}

.contact-form label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--dark);
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background-color: white;
  color: var(--text);
  font-size: 1rem;
  transition: var(--transition);
  font-family: inherit;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  outline: none;
}

.contact-form textarea {
  resize: vertical;
  min-height: 120px;
}

.contact-details {
  background: linear-gradient(
    135deg,
    var(--primary) 0%,
    var(--primary-dark) 100%
  );
  border-radius: var(--border-radius);
  padding: 40px;
  color: white;
  position: relative;
  overflow: hidden;
}

.contact-details::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="dots" width="20" height="20" patternUnits="userSpaceOnUse"><circle cx="10" cy="10" r="1.5" fill="white" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23dots)"/></svg>');
  pointer-events: none;
}

.contact-details h3 {
  font-size: 1.75rem;
  margin-bottom: 32px;
  color: white;
  position: relative;
  display: flex;
  align-items: center;
}

.contact-details h3 i {
  margin-right: 16px;
}

.contact-info {
  position: relative;
}

.info-item {
  display: flex;
  margin-bottom: 32px;
}

.info-item i {
  font-size: 1.5rem;
  margin-right: 20px;
  margin-top: 4px;
}

.info-item h4 {
  font-size: 1.125rem;
  margin-bottom: 8px;
  color: white;
  font-weight: 600;
}

.info-item p {
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.6;
  margin-bottom: 0;
}

/* Enhanced Footer */
.footer {
  background: var(--dark);
  color: white;
  padding: 80px 0;
}

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

.footer-logo {
  display: flex;
  align-items: center;
  font-size: 1.75rem;
  font-weight: 700;
  color: white;
  margin-bottom: 24px;
}

.footer-logo i {
  margin-right: 12px;
  font-size: 2rem;
}

.footer-text {
  margin-bottom: 32px;
}

.footer-text p {
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 8px;
}

.footer-social {
  display: flex;
  gap: 20px;
}

.footer-social a {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
  transition: var(--transition);
}

.footer-social a:hover {
  background: var(--primary);
  transform: translateY(-4px);
}

/* Back to Top Button */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  background: var(--primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
  transition: var(--transition);
  opacity: 0;
  visibility: hidden;
  z-index: 99;
}

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

.back-to-top:hover {
  background: var(--primary-dark);
  transform: translateY(-4px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
  color: white;
}

/* Success Message */
.success-message {
  text-align: center;
  padding: 40px 0;
}

.success-message h3 {
  font-size: 1.75rem;
  margin-bottom: 16px;
  color: var(--dark);
}

.success-message p {
  color: var(--text);
  font-size: 1.125rem;
  line-height: 1.7;
}

/* Responsive Styles */
@media (max-width: 1200px) {
  .hero-text h1 {
    font-size: 3.25rem;
  }

  .subtitle {
    font-size: 1.375rem;
  }

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

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

  .grid-container {
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  }
}

@media (max-width: 992px) {
  .hero-content {
    flex-direction: column;
    gap: 40px;
  }

  .hero-text {
    max-width: 100%;
  }

  .hero-image {
    max-width: 100%;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

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

  .prediction-content {
    grid-template-columns: 1fr;
  }

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

  .menu-toggle {
    display: block;
  }

  .navbar {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    background: white;
    padding: 20px;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    z-index: 99;
  }

  .navbar.active {
    transform: translateY(0);
  }

  .tabs {
    flex-direction: column;
    width: 100%;
  }

  .tabs li {
    width: 100%;
  }

  .tabs a {
    width: 100%;
    padding: 16px;
  }

  body.menu-open {
    overflow: hidden;
  }
}

@media (max-width: 768px) {
  section {
    padding: 80px 0;
  }

  .hero-section {
    padding: 140px 0 80px;
  }

  .hero-text h1 {
    font-size: 2.75rem;
  }

  .subtitle {
    font-size: 1.25rem;
  }

  .section-header h2 {
    font-size: 2.25rem;
  }

  .section-header p {
    font-size: 1.125rem;
  }

  .feature-boxes {
    grid-template-columns: 1fr;
  }

  .process-flow {
    grid-template-columns: 1fr;
  }

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

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

  .form-card,
  .result-card {
    padding: 24px;
  }

  .contact-form,
  .contact-details {
    padding: 24px;
  }

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

@media (max-width: 576px) {
  .hero-text h1 {
    font-size: 2.25rem;
  }

  .subtitle {
    font-size: 1.125rem;
  }

  .hero-text p {
    font-size: 1rem;
  }

  .btn {
    padding: 12px 24px;
    font-size: 0.95rem;
  }

  .section-header h2 {
    font-size: 2rem;
  }

  .section-header p {
    font-size: 1rem;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .footer {
    padding: 60px 0;
  }
}

/* New Prediction Tabs Styles */
.prediction-tabs {
  display: flex;
  background: var(--light-gray);
  border-radius: var(--border-radius);
  padding: 4px;
  margin-top: 40px;
  margin-bottom: 40px;
  overflow: hidden;
}

.prediction-tab {
  flex: 1;
  background: transparent;
  border: none;
  padding: 16px 24px;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.prediction-tab i {
  font-size: 1.1rem;
}

.prediction-tab:hover {
  color: var(--primary);
}

.prediction-tab.active {
  background: white;
  color: var(--primary);
  font-weight: 600;
  box-shadow: var(--shadow);
  border-radius: var(--border-radius);
}

.prediction-tab-content {
  display: none;
}

.prediction-tab-content.active {
  display: block;
}

/* Batch Prediction Styles */
.upload-section {
  margin-bottom: 40px;
}

.upload-area {
  border: 3px dashed var(--primary-light);
  border-radius: var(--border-radius);
  padding: 40px;
  text-align: center;
  background: white;
  transition: all var(--transition);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.upload-area::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(59, 130, 246, 0.05),
    transparent
  );
  transition: left 0.5s ease;
}

.upload-area:hover::before {
  left: 100%;
}

.upload-area:hover,
.upload-area.dragover {
  border-color: var(--primary);
  background: rgba(59, 130, 246, 0.05);
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(59, 130, 246, 0.15);
}

.upload-icon {
  width: 80px;
  height: 80px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  color: white;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.upload-icon i {
  font-size: 2rem;
}

.upload-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 12px;
}

.upload-description {
  color: var(--text-light);
  margin-bottom: 24px;
  font-size: 1rem;
}

.upload-btn {
  background: var(--primary);
  color: white;
  border: none;
  padding: 14px 28px;
  border-radius: var(--border-radius);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: var(--transition);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.2);
}

.upload-btn:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.3);
}

.file-input {
  display: none;
}

.file-types {
  margin-top: 16px;
  color: var(--text-light);
  font-size: 0.875rem;
}

.status-section {
  margin-bottom: 40px;
}

.status {
  padding: 16px 20px;
  border-radius: var(--border-radius);
  margin-bottom: 20px;
  display: none;
  font-weight: 500;
  box-shadow: var(--shadow-sm);
  border-left: 4px solid;
}

.status.info {
  background: rgba(59, 130, 246, 0.1);
  color: var(--primary);
  border-left-color: var(--primary);
}

.status.error {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
  border-left-color: var(--danger);
}

.status.success {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
  border-left-color: var(--success);
}

.loader {
  display: none;
  text-align: center;
  padding: 32px;
}

.spinner {
  width: 50px;
  height: 50px;
  border: 4px solid rgba(59, 130, 246, 0.1);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto 16px;
}

.loader p {
  color: var(--text-light);
  font-weight: 500;
}

.tabs {
  display: flex;
  background: var(--light-gray);
  border-radius: var(--border-radius);
  padding: 4px;
  margin-bottom: 24px;
  overflow: hidden;
}

.tab {
  flex: 1;
  background: transparent;
  border: none;
  padding: 12px 20px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.tab i {
  font-size: 1rem;
}

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

.tab.active {
  background: white;
  color: var(--primary);
  font-weight: 600;
  box-shadow: var(--shadow);
  border-radius: var(--border-radius);
}

.tab-content {
  display: none;
}

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

.content-card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  border: 1px solid var(--border);
}

.card-header {
  background: var(--light-gray);
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}

.card-header h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--dark);
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 0;
}

.card-header i {
  color: var(--primary);
}

.table-container {
  max-height: 500px;
  overflow: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: white;
}

th,
td {
  padding: 14px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

th {
  background: var(--primary);
  font-weight: 600;
  color: white;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  position: sticky;
  top: 0;
  z-index: 10;
}

tr:hover td {
  background: rgba(59, 130, 246, 0.05);
}

tr:last-child td {
  border-bottom: none;
}

.analysis-result table th {
  background: var(--primary);
  color: white;
}

.analysis-result tr:nth-child(even) td {
  background: rgba(59, 130, 246, 0.03);
}

.predicted-status-dropout,
.predicted-status-graduate {
  padding: 6px 12px;
  border-radius: 50px;
  font-size: 0.875rem;
  font-weight: 600;
  display: inline-block;
  text-align: center;
  min-width: 90px;
}

.predicted-status-dropout {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.predicted-status-graduate {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.placeholder-content {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-light);
}

.placeholder-content i {
  font-size: 4rem;
  color: var(--primary-light);
  margin-bottom: 24px;
  display: block;
  opacity: 0.6;
}

.placeholder-content h4 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 12px;
}

.placeholder-content p {
  font-size: 1rem;
  line-height: 1.5;
  max-width: 500px;
  margin: 0 auto;
}

/* Responsive adjustments for batch prediction */
@media (max-width: 768px) {
  .upload-area {
    padding: 30px 20px;
  }

  .upload-icon {
    width: 60px;
    height: 60px;
    margin-bottom: 16px;
  }

  .upload-icon i {
    font-size: 1.5rem;
  }

  .upload-title {
    font-size: 1.25rem;
  }

  .upload-btn {
    padding: 12px 20px;
    font-size: 0.95rem;
  }

  .prediction-tabs {
    flex-direction: column;
    gap: 8px;
  }

  .prediction-tab {
    border-radius: var(--border-radius);
  }

  .prediction-tab.active {
    border-radius: var(--border-radius);
  }

  th,
  td {
    padding: 10px 12px;
    font-size: 0.875rem;
  }

  .predicted-status-dropout,
  .predicted-status-graduate {
    padding: 4px 8px;
    font-size: 0.75rem;
    min-width: 70px;
  }
}

@media (max-width: 480px) {
  .upload-area {
    padding: 20px 16px;
  }

  .upload-icon {
    width: 50px;
    height: 50px;
  }

  .upload-icon i {
    font-size: 1.25rem;
  }

  .upload-title {
    font-size: 1.125rem;
  }

  .upload-description {
    font-size: 0.875rem;
  }

  .tabs {
    flex-direction: column;
    gap: 4px;
  }

  .tab {
    border-radius: var(--border-radius);
  }

  .tab.active {
    border-radius: var(--border-radius);
  }

  .placeholder-content {
    padding: 40px 16px;
  }

  .placeholder-content i {
    font-size: 3rem;
  }

  .placeholder-content h4 {
    font-size: 1.125rem;
  }

  .placeholder-content p {
    font-size: 0.875rem;
  }
}