/* --- Professional Typography & Base Styles --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

html {
  font-size: clamp(16px, 2.5vw, 18px);
  line-height: 1.6;
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  margin: 0 auto;
  padding: 0 1.5rem;
  max-width: 1200px;
  background: #fafbfc;
  color: #1a202c;
  font-weight: 400;
}

/* --- Professional Color System --- */
:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #dbeafe;
  --secondary: #64748b;
  --accent: #f59e0b;
  --success: #10b981;
  --card-bg: #ffffff;
  --card-border: #e2e8f0;
  --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --card-shadow-hover: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --text-muted: #6b7280;
  --border-light: #f1f5f9;
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-hero: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 50%, #f8fafc 100%);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #60a5fa;
    --primary-hover: #3b82f6;
    --primary-light: #1e3a8a;
    --card-bg: #1e293b;
    --card-border: #334155;
    --text-muted: #94a3b8;
    --border-light: #334155;
    --gradient-hero: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #334155 100%);
  }
  
  body {
    background: #0f172a;
    color: #f1f5f9;
  }
}

/* --- Enhanced Typography --- */
h1 {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.2;
  margin: 0.8em 0 0.5em;
  letter-spacing: -0.025em;
  color: #1a202c;
}

h2 {
  font-size: clamp(1.8rem, 4vw, 2.25rem);
  font-weight: 600;
  line-height: 1.3;
  margin: 1.5em 0 0.8em;
  color: #374151;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 1.2em 0 0.6em;
  color: var(--primary);
}

@media (prefers-color-scheme: dark) {
  h1 { color: #f1f5f9; }
  h2 { color: #e2e8f0; }
}

/* --- Professional Header --- */
header {
  text-align: center;
  padding: 4rem 0 3rem;
  background: var(--gradient-hero);
  border-radius: 16px;
  margin: 2rem 0 3rem;
  border: 1px solid var(--border-light);
}

.tag {
  color: var(--text-muted);
  font-size: 1.1rem;
  font-weight: 500;
  margin-top: 1rem;
  letter-spacing: 0.01em;
}

/* --- Hero Section Enhancement --- */
section[style*="padding:3rem 0"] {
  padding: 4rem 2rem !important;
  background: var(--gradient-primary) !important;
  border-radius: 20px !important;
  margin: 3rem 0 !important;
  border: none !important;
  box-shadow: var(--card-shadow-hover) !important;
  position: relative;
  overflow: hidden;
}

section[style*="padding:3rem 0"]: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"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="80" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="60" r="1" fill="rgba(255,255,255,0.1)"/></svg>');
  pointer-events: none;
}

section[style*="padding:3rem 0"] h2 {
  color: white !important;
  font-weight: 700 !important;
  text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

section[style*="padding:3rem 0"] p {
  color: rgba(255,255,255,0.9) !important;
  font-size: 1.1rem !important;
  font-weight: 500 !important;
}

section[style*="padding:3rem 0"] a {
  background: white !important;
  color: var(--primary) !important;
  font-weight: 600 !important;
  padding: 1rem 2rem !important;
  border-radius: 12px !important;
  text-decoration: none !important;
  display: inline-block !important;
  box-shadow: 0 4px 12px rgba(0,0,0,0.15) !important;
  transition: all 0.3s ease !important;
  position: relative;
  z-index: 1;
}

section[style*="padding:3rem 0"] a:hover {
  transform: translateY(-2px) !important;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2) !important;
}

/* --- Professional Cards --- */
.card {
  padding: 2rem;
  border: 1px solid var(--card-border);
  border-radius: 16px;
  background: var(--card-bg);
  box-shadow: var(--card-shadow);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  display: block;
  position: relative;
  overflow: hidden;
}

.card:before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform 0.3s ease;
}

.card:hover:before {
  transform: scaleX(1);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--card-shadow-hover);
  border-color: var(--primary-light);
}

.card h3 {
  margin-top: 0;
  font-size: 1.1rem;
  font-weight: 600;
  color: #1a202c;
}

@media (prefers-color-scheme: dark) {
  .card h3 { color: #f1f5f9; }
}

.cards {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  margin: 2rem 0;
}

/* --- Enhanced Sections --- */
section {
  padding: 3rem 0;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 1rem;
}

section:last-child {
  border-bottom: none;
}

main section {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 2.5rem;
  margin: 2rem 0;
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
}

/* --- Professional Forms --- */
form {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin: 2rem 0;
  flex-wrap: wrap;
}

input[type="email"] {
  flex: 1;
  min-width: 240px;
  padding: 1rem 1.25rem;
  border: 2px solid var(--card-border);
  border-radius: 12px;
  font-size: 1rem;
  background: var(--card-bg);
  transition: all 0.3s ease;
  font-family: inherit;
}

input[type="email"]:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

button {
  padding: 1rem 2rem;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  font-family: inherit;
  box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

button:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 8px rgba(37, 99, 235, 0.3);
}

/* --- Enhanced Links & Navigation --- */
a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s ease;
}

a:hover {
  color: var(--primary-hover);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

/* --- Professional Lists --- */
.list {
  list-style: none;
  padding: 0;
}

.list li {
  margin: 1rem 0;
  padding: 1rem;
  background: var(--card-bg);
  border-radius: 8px;
  border-left: 4px solid var(--primary);
  box-shadow: var(--card-shadow);
  transition: transform 0.2s ease;
}

.list li:hover {
  transform: translateX(4px);
}

/* --- Enhanced Footer --- */
footer {
  margin-top: 4rem;
  font-size: 0.9rem;
  text-align: center;
  color: var(--text-muted);
  border-top: 2px solid var(--border-light);
  padding: 3rem 0 2rem;
  background: var(--card-bg);
  border-radius: 12px 12px 0 0;
}

footer p {
  margin: 0.5rem 0;
  line-height: 1.6;
}

/* --- Feature Tool Form Enhancement --- */
#feature-tool {
  margin-top: 2rem;
  padding: 2rem;
  background: var(--primary-light);
  border-radius: 16px;
  border: 1px solid var(--primary);
  box-shadow: var(--card-shadow);
}

#feature-tool h3 {
  margin-top: 0;
  color: var(--primary);
}

#feature-tool form {
  flex-direction: column;
  align-items: stretch;
}

#feature-tool input,
#feature-tool textarea {
  padding: 0.75rem 1rem;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  font-family: inherit;
  background: var(--card-bg);
}

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

/* --- Responsive Enhancements --- */
@media (max-width: 768px) {
  body {
    padding: 0 1rem;
  }
  
  header {
    padding: 3rem 1rem 2rem;
    margin: 1rem 0 2rem;
  }
  
  main section {
    padding: 2rem 1.5rem;
  }
  
  .cards {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  form {
    flex-direction: column;
    align-items: stretch;
  }
  
  input[type="email"] {
    min-width: unset;
  }
}

/* --- Advanced Animations --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.card {
  animation: fadeInUp 0.6s ease-out;
}

/* --- Professional Touches --- */
::selection {
  background: var(--primary-light);
  color: var(--primary);
}

::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--border-light);
}

::-webkit-scrollbar-thumb {
  background: var(--text-muted);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary);
}

/* --- Focus States for Accessibility --- */
*:focus {
  outline: 2px dashed var(--primary);
  outline-offset: 2px;
}

button:focus,
input:focus,
textarea:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}