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

html,
body {
  height: 100%;
}

body {
  font-family: "Roboto", -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background: linear-gradient(135deg, 
    #a78bfa 0%, 
    #c4b5fd 15%, 
    #ddd6fe 30%, 
    #e9d5ff 45%, 
    #f3e8ff 60%, 
    #fce7f3 75%, 
    #fef3c7 90%, 
    #dbeafe 100%);
  background-size: 400% 400%;
  animation: gradientShift 20s ease infinite;
  position: relative;
  color: #1a1a1a;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: flex-start;
  min-height: 100vh;
  padding: 0;
  cursor: default; /* normal cursor */
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.4) 0%, transparent 60%),
    radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.3) 0%, transparent 60%),
    radial-gradient(circle at 40% 20%, rgba(255, 255, 255, 0.2) 0%, transparent 50%),
    radial-gradient(circle at 60% 70%, rgba(255, 255, 255, 0.25) 0%, transparent 55%);
  pointer-events: none;
  z-index: 0;
}

body > * {
  position: relative;
  z-index: 1;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.site-header {
  width: 100%;
  margin: 0;
  padding: 1.2rem 1.5rem;
  background: linear-gradient(120deg, rgba(15, 23, 42, 0.95), rgba(30, 41, 59, 0.88));
  backdrop-filter: blur(22px) saturate(200%);
  border-bottom: 1px solid rgba(148, 163, 184, 0.45);
  box-shadow:
    0 18px 45px rgba(15, 23, 42, 0.55),
    0 0 0 1px rgba(255, 255, 255, 0.05);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}

/* Navigation */
.main-nav {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav-link {
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 0.75rem;
  transition: all 300ms cubic-bezier(0.16, 1, 0.3, 1);
  cursor: none;
  position: relative;
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.nav-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.1));
  border-radius: 0.75rem;
  opacity: 0;
  transition: opacity 300ms ease;
}

.nav-link:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.nav-link:hover::before {
  opacity: 1;
}

.nav-link.active {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.4);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  font-weight: 600;
}

.nav-link.nav-cta {
  background: linear-gradient(135deg, #7c3aed, #06b6d4);
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.35);
  box-shadow:
    0 12px 30px rgba(124, 58, 237, 0.35),
    0 0 0 1px rgba(255, 255, 255, 0.15);
  letter-spacing: 0.02em;
  font-weight: 600;
}

.nav-link.nav-cta:hover {
  background: linear-gradient(135deg, #8b5cf6, #22d3ee);
  box-shadow:
    0 16px 40px rgba(139, 92, 246, 0.45),
    0 0 0 1px rgba(255, 255, 255, 0.25);
  transform: translateY(-2px) scale(1.01);
}

.site-footer {
  margin-top: 4rem;
  padding: 3rem 2rem;
  justify-content: center;
  border-top: 1px solid rgba(167, 139, 250, 0.3);
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(20px) saturate(180%);
  border-radius: 2rem 2rem 0 0;
  box-shadow: 0 -10px 40px rgba(167, 139, 250, 0.15);
}

.footer-content {
  max-width: 960px;
  margin: 0 auto;
  text-align: center;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  margin-bottom: 1rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-weight: 600;
  font-size: 0.95rem;
  color: #6b21a8;
  text-shadow: none;
}

.footer-tagline {
  color: #7c3aed;
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  font-weight: 400;
  text-shadow: none;
}

.footer-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.footer-links a {
  color: #6b21a8;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 0.4rem 0.8rem;
  border-radius: 0.5rem;
  transition: all 300ms ease;
  cursor: none;
  background: rgba(167, 139, 250, 0.1);
  border: 1px solid rgba(167, 139, 250, 0.2);
}

.footer-links a:hover {
  color: #5b21b6;
  background: rgba(167, 139, 250, 0.2);
  border-color: rgba(167, 139, 250, 0.4);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(167, 139, 250, 0.2);
}

.footer-links .separator {
  color: rgba(167, 139, 250, 0.5);
  font-size: 0.8rem;
}

.site-footer small {
  display: block;
  text-align: center;
  color: #7c3aed;
  font-size: 0.85rem;
  font-weight: 400;
  text-shadow: none;
  opacity: 0.8;
}

.logo {
  display: inline-flex;
  align-items: center;
}

.logo-link {
  display: inline-flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none;
  color: inherit;
}

.logo-icon {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  background: transparent;
  box-shadow:
    0 8px 25px rgba(124, 58, 237, 0.3),
    0 2px 8px rgba(124, 58, 237, 0.2);
  display: grid;
  place-items: center;
  transition: transform 300ms ease, box-shadow 300ms ease;
}

.logo:hover .logo-icon {
  transform: translateY(-2px);
  box-shadow:
    0 12px 35px rgba(124, 58, 237, 0.4),
    0 4px 12px rgba(124, 58, 237, 0.3);
}

.logo-icon svg {
  width: 100%;
  height: 100%;
  display: block;
}

.logo-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.logo-title {
  font-size: 1.08rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.logo-subtitle {
  font-size: 0.82rem;
  color: rgba(209, 213, 219, 0.95);
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

/* Override for homepage hero section */
.hero {
  width: 100%;
  max-width: 960px;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* Page hero for About/Contact */
.page-hero {
  width: 100%;
  margin-bottom: 2rem;
  display: flex;
  justify-content: center;
}

.page-card {
  width: 100%;
  max-width: 100% !important;
  text-align: center;
  margin: 0 auto;
  padding: 1.75rem 2rem !important;
  border-radius: 1.25rem !important;
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.08) !important;
}

.page-card h1 {
  text-align: center;
}

.page-card .subtitle {
  text-align: center;
}

/* Content section for About/Contact */
.content-section {
  width: 100%;
  max-width: 1200px;
  display: flex;
  flex-direction: column;
  gap: 0;
  align-items: center;
  margin: 0 auto;
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border-radius: 0;
  padding: 2rem 1.5rem;
  box-shadow: none;
  border: none;
  overflow: visible;
}

/* Unified content sections - seamless design */
.content-card,
.example-box,
.dpi-card {
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border-radius: 0;
  padding: 0;
  box-shadow: none;
  border: none;
  transition: none;
  width: 100%;
  box-sizing: border-box;
  position: relative;
  overflow: visible;
  margin-bottom: 4rem;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.content-card:last-child,
.example-box:last-child,
.dpi-card:last-child {
  margin-bottom: 0;
}

.chart-container {
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  border-radius: 1rem;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: all 300ms ease;
  width: 100%;
  box-sizing: border-box;
  position: relative;
  overflow: visible;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.chart-container:hover {
  background: rgba(255, 255, 255, 0.8);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.content-card::before,
.example-box::before,
.dpi-card::before,
.chart-container::before {
  display: none;
}

.content-card {
  animation: cardIn 600ms ease-out;
}

.content-card h2 {
  font-size: 2rem;
  font-weight: 700;
  color: #1a202c;
  margin-bottom: 1.5rem;
  margin-top: 0;
  letter-spacing: -0.02em;
  line-height: 1.2;
  padding: 0;
}

.content-card h3 {
  font-size: 1.375rem;
  font-weight: 600;
  color: #2d3748;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  padding: 0;
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.content-card p {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: #2d3748;
  margin-bottom: 1.5rem;
  padding: 0;
  font-weight: 400;
  letter-spacing: -0.01em;
}

.feature-list {
  list-style: none;
  padding-left: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.feature-list li {
  padding-left: 1.75rem;
  position: relative;
  font-size: 1.0625rem;
  line-height: 1.8;
  color: #2d3748;
  margin-bottom: 0.5rem;
}

.feature-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #6366f1;
  font-weight: 700;
  font-size: 1rem;
}

.feature-list li strong {
  color: #111827;
  font-weight: 600;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-top: 1rem;
  align-items: stretch;
  padding: 0;
}

.grid-item {
  display: flex;
  flex-direction: column;
  height: 100%;
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  border-radius: 1rem;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: all 300ms ease;
}

.grid-item:hover {
  background: rgba(255, 255, 255, 0.8);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

/* Hover effects for interactive boxes */
.chart-container:hover,
.example-box:hover {
  background: rgba(255, 255, 255, 0.02);
}

.grid-item h3 {
  font-size: 1rem;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.grid-item p {
  font-size: 0.9rem;
  margin-bottom: 0;
  color: #6b7280;
}

.dpi-list {
  list-style: none;
  padding-left: 0;
  padding: 0;
  margin-top: 1rem;
}

.dpi-list li {
  padding: 0.875rem 1rem;
  margin-bottom: 0.75rem;
  background: rgba(249, 250, 251, 0.8);
  border-radius: 0.75rem;
  border-left: 4px solid rgba(102, 126, 234, 0.6);
  font-size: 1rem;
  line-height: 1.7;
  color: #2d3748;
  font-weight: 400;
}

.dpi-list li strong {
  color: #111827;
}

.cta-card {
  text-align: center;
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  padding: 4rem 0 !important;
  margin: 4rem auto 0 !important;
  border-radius: 0;
  border: none;
  box-shadow: none;
  position: relative;
  overflow: visible;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  max-width: 800px;
}

.cta-card::before,
.cta-card::after {
  display: none;
}

.cta-card h2 {
  margin: 0 0 1.25rem 0;
  padding: 0;
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, #6b21a8 0%, #7c3aed 50%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
  line-height: 1.2;
  position: relative;
  z-index: 1;
  text-align: center;
  width: 100%;
}

.cta-card p {
  margin: 0 auto 2.5rem;
  padding: 0;
  font-size: 1.2rem;
  color: #6b21a8;
  line-height: 1.7;
  font-weight: 500;
  position: relative;
  z-index: 1;
  max-width: 600px;
  text-align: center;
  width: 100%;
}

.cta-card .btn {
  position: relative;
  z-index: 1;
  padding: 1.15rem 3rem;
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, #7c3aed 0%, #a855f7 100%);
  box-shadow: 
    0 12px 35px rgba(124, 58, 237, 0.4),
    0 0 0 0 rgba(124, 58, 237, 0.5),
    inset 0 1px 0 rgba(255, 255, 255, 0.3);
  transition: all 300ms cubic-bezier(0.16, 1, 0.3, 1);
  margin: 0;
  display: inline-block;
}

.cta-card .btn:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: 
    0 18px 45px rgba(124, 58, 237, 0.5),
    0 0 0 4px rgba(124, 58, 237, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.4);
  background-position: 100% 0;
}

/* Contact page styles */
.contact-wrapper {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 2rem;
  margin-bottom: 1.5rem;
}

.contact-info-card,
.contact-form-card {
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: blur(16px);
  border-radius: 1.5rem;
  padding: 2rem 2.25rem;
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.08);
  border: 1px solid rgba(148, 163, 184, 0.22);
  animation: cardIn 600ms ease-out;
}

.contact-info-card h2,
.contact-form-card h2 {
  font-size: 1.4rem;
  font-weight: 600;
  color: #111827;
  margin-bottom: 1rem;
}

.contact-details {
  margin-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.contact-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.contact-icon {
  width: 40px;
  height: 40px;
  min-width: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(6, 182, 212, 0.1));
  border-radius: 0.75rem;
  color: #6366f1;
}

.contact-icon svg {
  width: 20px;
  height: 20px;
}

.contact-item h3 {
  font-size: 0.95rem;
  font-weight: 600;
  color: #111827;
  margin: 0 0 0.25rem 0;
}

.contact-item p {
  font-size: 0.9rem;
  color: #6b7280;
  margin: 0;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

.contact-form .field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.contact-form input[type="text"],
.contact-form input[type="email"],
.contact-form textarea {
  width: 100%;
  padding: 0.7rem 0.9rem;
  border-radius: 0.9rem;
  border: 1px solid rgba(148, 163, 184, 0.7);
  background-color: rgba(249, 250, 251, 0.9);
  color: #111827;
  font-size: 0.95rem;
  font-family: inherit;
  outline: none;
  transition: border-color 160ms ease, box-shadow 160ms ease,
    transform 160ms ease, background-color 160ms ease;
  cursor: none;
}

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

.contact-form input[type="text"]:hover,
.contact-form input[type="email"]:hover,
.contact-form textarea:hover {
  transform: translateY(-1px);
  background-color: #ffffff;
}

.contact-form input[type="text"]:focus,
.contact-form input[type="email"]:focus,
.contact-form textarea:focus {
  border-color: #6366f1;
  box-shadow: 0 0 0 1px rgba(129, 140, 248, 0.6),
    0 12px 25px rgba(15, 23, 42, 0.15);
  background-color: #ffffff;
}

.contact-result {
  padding: 0.9rem 1rem;
  border-radius: 0.75rem;
  font-size: 0.9rem;
  text-align: center;
  margin-top: 0.5rem;
  opacity: 0;
  transform: translateY(-8px);
  transition: opacity 260ms ease, transform 260ms ease;
}

.contact-result.success {
  opacity: 1;
  transform: translateY(0);
  background: rgba(16, 185, 129, 0.1);
  color: #059669;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

/* How to Calculate page styles */
.formula-box {
  margin: 1.5rem 0;
  padding: 2rem 2.25rem;
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
  border-radius: 1.25rem;
  border: 2px solid rgba(102, 126, 234, 0.2);
  text-align: center;
  width: 100%;
  box-sizing: border-box;
}

.formula-main {
  margin-bottom: 1rem;
}

.formula-text {
  font-size: 1.8rem;
  font-weight: 700;
  color: #6366f1;
  font-family: 'Courier New', monospace;
  display: inline-block;
  padding: 0.5rem 1.5rem;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 0.75rem;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.2);
}

.formula-explanation {
  font-size: 0.95rem;
  color: #4b5563;
  margin: 0;
}

.steps-container {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 1rem;
  width: 100%;
  padding: 0;
}

.step-item {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  border-radius: 1rem;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: all 300ms ease;
}

.step-item:hover {
  transform: translateY(-2px);
  background: rgba(255, 255, 255, 0.8);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.step-number {
  width: 48px;
  height: 48px;
  min-width: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #6366f1, #06b6d4);
  color: white;
  font-size: 1.5rem;
  font-weight: 700;
  border-radius: 50%;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.step-content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #111827;
  margin: 0 0 0.5rem 0;
}

.step-content p {
  font-size: 0.95rem;
  color: #4b5563;
  margin: 0;
  line-height: 1.7;
}

.dpi-reference {
  margin-top: 0.5rem;
  padding-left: 1.5rem;
}

.dpi-reference li {
  font-size: 0.9rem;
  line-height: 1.6;
  color: #4b5563;
  margin-bottom: 0.3rem;
}

.example-box {
  margin: 0 0 3rem 0;
  border-left: none;
  padding: 1.5rem 1.5rem 1.5rem 2rem;
  border-left: 4px solid rgba(102, 126, 234, 0.3);
  background: rgba(102, 126, 234, 0.05);
  border-radius: 0.75rem;
}

.example-box h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #111827;
  margin: 0 0 1rem 0;
}

.example-calculation {
  margin-top: 0.75rem;
}

.example-calculation > p {
  font-size: 0.95rem;
  color: #6b7280;
  margin-bottom: 0.75rem;
}

.calculation-steps {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 1rem;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 0.75rem;
  font-family: 'Courier New', monospace;
}

.calc-step {
  font-size: 1rem;
  color: #4b5563;
  padding: 0.4rem 0;
}

.calc-result {
  margin-top: 0.5rem;
  padding-top: 0.75rem;
  border-top: 2px solid rgba(99, 102, 241, 0.2);
  font-size: 1.05rem;
  color: #111827;
  font-weight: 600;
}

.dpi-comparison {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 1.5rem;
  align-items: stretch;
  padding: 0;
}

.dpi-card {
  display: flex;
  flex-direction: column;
  height: 100%;
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  border-radius: 1rem;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: all 300ms ease;
}

.dpi-card:hover {
  background: rgba(255, 255, 255, 0.8);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.dpi-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #111827;
  margin: 0 0 0.5rem 0;
}

.dpi-card > p {
  font-size: 0.9rem;
  color: #6b7280;
  margin-bottom: 0.75rem;
  font-weight: 500;
}

.dpi-card ul {
  list-style: none;
  padding-left: 0;
  margin: 0;
}

.dpi-card li {
  font-size: 0.9rem;
  color: #4b5563;
  padding: 0.3rem 0;
  padding-left: 1.2rem;
  position: relative;
}

.dpi-card li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: #6366f1;
  font-weight: 700;
}

.chart-wrapper {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  margin-top: 1rem;
  width: 100%;
  padding: 0;
}


.chart-container h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #111827;
  margin: 0 0 1rem 0;
}

.tips-list {
  list-style: none;
  padding-left: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1rem;
}

.tips-list li {
  padding: 1.5rem 1.75rem;
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  border-radius: 1rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-left: 4px solid rgba(102, 126, 234, 0.5);
  font-size: 1.0625rem;
  line-height: 1.8;
  color: #2d3748;
  transition: all 300ms ease;
  font-weight: 400;
}

.tips-list li:hover {
  transform: translateY(-1px);
  background: rgba(255, 255, 255, 0.8);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.tips-list li strong {
  color: #111827;
  font-weight: 600;
}

.hero {
  width: 100%;
  max-width: 960px;
  display: flex;
  justify-content: center;
}

.card {
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-radius: 2rem;
  padding: 3.5rem 4rem;
  box-shadow: 
    0 20px 60px rgba(0, 0, 0, 0.15),
    0 0 0 1px rgba(255, 255, 255, 0.5) inset,
    0 1px 0 rgba(255, 255, 255, 0.6) inset;
  max-width: 600px;
  width: 100%;
  border: 1px solid rgba(255, 255, 255, 0.3);
  animation: cardIn 800ms cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.8), transparent);
}

.card h1 {
  font-size: clamp(2rem, 3vw + 1rem, 2.75rem);
  font-weight: 700;
  color: #1a202c;
  margin-bottom: 0.75rem;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.15;
}

.subtitle {
  font-size: 1.125rem;
  color: #4a5568;
  margin-bottom: 2.5rem;
  line-height: 1.7;
  font-weight: 400;
  letter-spacing: -0.01em;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1.3rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

label {
  font-size: 0.9375rem;
  font-weight: 600;
  color: #2d3748;
  margin-bottom: 0.5rem;
  display: block;
  letter-spacing: -0.01em;
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

input[type="number"],
input[type="text"],
input[type="email"],
textarea {
  width: 100%;
  padding: 1rem 1.25rem;
  padding-right: 3.1rem;
  border-radius: 1rem;
  border: 2px solid rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  color: #1a202c;
  font-size: 1rem;
  outline: none;
  transition: all 300ms cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 
    0 4px 12px rgba(0, 0, 0, 0.05),
    inset 0 1px 0 rgba(255, 255, 255, 0.8);
  font-weight: 400;
  line-height: 1.5;
}

input[type="number"]::placeholder {
  color: #9ca3af;
}

input[type="number"]:hover,
input[type="text"]:hover,
input[type="email"]:hover,
textarea:hover {
  transform: translateY(-1px);
  background-color: rgba(255, 255, 255, 0.95);
  border-color: rgba(255, 255, 255, 0.5);
  box-shadow: 
    0 6px 20px rgba(0, 0, 0, 0.08),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
}

input[type="number"]:focus,
input[type="text"]:focus,
input[type="email"]:focus,
textarea:focus {
  border-color: rgba(102, 126, 234, 0.6);
  box-shadow: 
    0 0 0 4px rgba(102, 126, 234, 0.15),
    0 8px 25px rgba(102, 126, 234, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
  background-color: #ffffff;
  transform: translateY(-1px);
}

.input-icon {
  position: absolute;
  right: 0.9rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: #6b7280;
  pointer-events: none;
}

.dpi-icon {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: #9ca3af;
  stroke-width: 1.1;
}

.dpi-icon rect:first-child {
  fill: #f3f4ff;
  stroke: #a5b4fc;
}

.btn {
  margin-top: 0.5rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  border: none;
  border-radius: 999px;
  padding: 0.8rem 1.6rem;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: none; /* custom cursor will appear */
  transition: transform 160ms ease, box-shadow 160ms ease,
    background-position 220ms ease, opacity 120ms ease;
}

.btn.primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  background-size: 200% 200%;
  color: #ffffff;
  box-shadow: 
    0 10px 30px rgba(102, 126, 234, 0.4),
    0 0 0 0 rgba(102, 126, 234, 0.5),
    inset 0 1px 0 rgba(255, 255, 255, 0.3);
  position: relative;
  overflow: hidden;
  font-weight: 600;
  letter-spacing: 0.3px;
}

.btn.primary::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transition: left 0.5s ease;
}

.btn.primary:hover::before {
  left: 100%;
}

.btn.primary:hover {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 
    0 15px 40px rgba(102, 126, 234, 0.5),
    0 0 0 4px rgba(102, 126, 234, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.4);
  background-position: 100% 0;
}

.btn.primary:active {
  transform: translateY(0) scale(1);
  box-shadow: 
    0 5px 15px rgba(102, 126, 234, 0.4),
    0 0 0 2px rgba(102, 126, 234, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.btn-icon svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: #e5e7eb;
  stroke-width: 1.2;
}

.result {
  margin-top: 2rem;
  min-height: 1.5em;
  font-size: 1.25rem;
  font-weight: 700;
  color: #111827;
  opacity: 0;
  transform: translateY(8px);
  padding: 1.25rem 1.5rem;
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
  border-radius: 1rem;
  border: 2px solid rgba(102, 126, 234, 0.2);
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.15);
}

.result.visible {
  animation: resultIn 400ms cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.helper-text {
  margin-top: 0.5rem;
  font-size: 0.8rem;
  color: #9ca3af;
}

.helper-text strong {
  color: #6b7280;
}

/* SEO / content section */
.seo-section {
  max-width: 1200px;
  width: 100%;
  margin: 5rem auto 0;
  color: #2d3748;
  padding: 0 1.5rem;
}

.seo-inner {
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border-radius: 0;
  padding: 0;
  border: none;
  box-shadow: none;
}

.info-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1.15fr);
  gap: 3rem;
  align-items: flex-start;
  margin-bottom: 3rem;
}

.info-copy h2 {
  font-size: 2rem;
  font-weight: 700;
  color: #1a202c;
  margin-bottom: 1.5rem;
  margin-top: 0;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.info-copy h3 {
  font-size: 1.375rem;
  font-weight: 600;
  color: #2d3748;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.info-copy p {
  font-size: 1.0625rem;
  line-height: 1.8;
  color: #2d3748;
  margin-bottom: 1.5rem;
  font-weight: 400;
  letter-spacing: -0.01em;
}

.info-copy ol,
.info-copy ul {
  padding-left: 1.5rem;
  margin-top: 0.5rem;
  margin-bottom: 1.5rem;
  font-size: 1.0625rem;
  line-height: 1.8;
  color: #2d3748;
}

.info-copy li + li {
  margin-top: 0.2rem;
}

.table-wrapper {
  margin-top: 0.8rem;
  overflow-x: auto;
}

.reference-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin-top: 0.3rem;
}

.reference-table th,
.reference-table td {
  padding: 0.5rem 0.6rem;
  text-align: left;
  border-bottom: 1px solid rgba(209, 213, 219, 0.7);
}

.reference-table thead th {
  font-size: 0.86rem;
  font-weight: 600;
  color: #111827;
  background: #f3f4ff;
}

.reference-table tbody tr:nth-child(even) {
  background: #f9fafb;
}

.reference-table tbody tr:hover {
  background: #eef2ff;
}

.info-visual img {
  width: 100%;
  border-radius: 1.5rem;
  display: block;
  object-fit: cover;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.faq {
  margin-top: 3rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 2rem;
}

.faq h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: #111827;
  margin-bottom: 1.25rem;
  letter-spacing: -0.01em;
}

.faq details {
  border-radius: 1rem;
  background: rgba(249, 250, 251, 0.6);
  backdrop-filter: blur(10px);
  padding: 1rem 1.25rem;
  margin-bottom: 0.75rem;
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: all 300ms ease;
}

.faq details[open] {
  background: rgba(255, 255, 255, 0.8);
  border-color: rgba(102, 126, 234, 0.4);
  box-shadow: 0 8px 20px rgba(102, 126, 234, 0.15);
  transform: translateY(-1px);
}

.faq summary {
  font-size: 1.0625rem;
  font-weight: 600;
  color: #1a202c;
  cursor: none;
  list-style: none;
  line-height: 1.5;
  letter-spacing: -0.01em;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq p {
  font-size: 1.0625rem;
  margin-top: 0.75rem;
  color: #2d3748;
  line-height: 1.8;
  font-weight: 400;
}

/* Custom cursor */
.cursor,
.cursor-outline {
  position: fixed;
  top: 0;
  left: 0;
  width: 16px;
  height: 16px;
  border-radius: 999px;
  pointer-events: none;
  z-index: 1000;
  transform: translate(-50%, -50%);
  mix-blend-mode: multiply;
}

.cursor {
  background: radial-gradient(circle at 30% 30%, #6366f1, #06b6d4);
  box-shadow: 0 0 12px rgba(79, 70, 229, 0.7);
  transition: width 140ms ease, height 140ms ease, transform 80ms ease,
    opacity 160ms ease, background 160ms ease;
}

.cursor-outline {
  width: 32px;
  height: 32px;
  border: 1px solid rgba(129, 140, 248, 0.7);
  background: radial-gradient(circle, rgba(129, 140, 248, 0.18), transparent);
  transition: width 180ms ease, height 180ms ease, opacity 160ms ease,
    border-color 160ms ease;
}

body.cursor-hidden .cursor,
body.cursor-hidden .cursor-outline {
  opacity: 0;
}

.cursor-interactive {
  width: 24px;
  height: 24px;
  background: radial-gradient(circle at 30% 30%, #f97316, #ec4899);
}

.cursor-outline-interactive {
  width: 44px;
  height: 44px;
  border-color: rgba(236, 72, 153, 0.9);
}

/* Define which elements are interactive for the cursor */
button,
input,
textarea,
a,
.nav-link,
details summary {
  cursor: none; /* keep system cursor hidden consistently */
}

/* Transitions & animations */
@keyframes cardIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.96);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes resultIn {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* Responsive */
@media (max-width: 768px) {
  .contact-wrapper {
    grid-template-columns: 1fr;
  }

  .grid-2 {
    grid-template-columns: 1fr;
  }

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

  .dpi-comparison {
    grid-template-columns: 1fr;
  }

  .formula-text {
    font-size: 1.4rem;
    padding: 0.4rem 1rem;
  }

  .step-item {
    flex-direction: column;
    gap: 1rem;
  }

  .step-number {
    width: 40px;
    height: 40px;
    min-width: 40px;
    font-size: 1.2rem;
  }

  /* Uniform padding for mobile */
  .content-card,
  .example-box,
  .dpi-card,
  .chart-container,
  .grid-item,
  .step-item {
    padding: 1.5rem 1.5rem;
  }
}

@media (max-width: 640px) {
  body {
    padding: 1rem;
    background-size: 300% 300%;
  }

  .site-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
    padding: 0.85rem 1.25rem;
    margin-bottom: 1.5rem;
  }

  .main-nav {
    width: 100%;
    justify-content: flex-start;
    gap: 0.5rem;
    flex-wrap: wrap;
  }

  .nav-link {
    font-size: 0.8rem;
    padding: 0.4rem 0.75rem;
  }

  .site-footer {
    padding: 2rem 1rem;
    margin-top: 3rem;
  }

  .footer-links {
    gap: 0.5rem;
  }

  .footer-links a {
    font-size: 0.85rem;
    padding: 0.3rem 0.6rem;
  }

  .card,
  .content-card,
  .contact-info-card,
  .contact-form-card,
  .example-box,
  .dpi-card,
  .chart-container,
  .grid-item,
  .step-item {
    padding: 1.5rem 1.25rem;
    border-radius: 1.25rem;
  }

  .card {
    padding: 2rem 1.5rem;
  }

  .card h1,
  .content-card h2 {
    font-size: 1.6rem;
  }

  .subtitle {
    font-size: 0.95rem;
  }

  .content-card h2 {
    font-size: 1.4rem;
  }

  .contact-info-card h2,
  .contact-form-card h2 {
    font-size: 1.2rem;
  }

  .result {
    font-size: 1.1rem;
    padding: 1rem 1.25rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}