/* Modern Download Time Estimator - CSS */

:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #818cf8;
  --secondary: #8b5cf6;
  --accent: #ec4899;
  --success: #10b981;
  --warning: #f59e0b;
  --dark: #0f172a;
  --dark-800: #1e293b;
  --dark-700: #334155;
  --gray: #64748b;
  --gray-light: #cbd5e1;
  --gray-lighter: #e2e8f0;
  --gray-lightest: #f1f5f9;
  --white: #ffffff;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --radius-sm: 0.5rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-xl: 2rem;
  --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);
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  line-height: 1.6;
  color: var(--dark);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  padding-bottom: 2rem;
  border-radius: 0 1rem 0 1rem;
}

/* NAVBAR */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
  animation: slideDown 0.5s ease-out;
}

@keyframes slideDown {
  from { transform: translateY(-100%); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

.navbar-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-sm) var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--dark);
  text-decoration: none;
  transition: transform 0.3s ease;
}

.navbar-brand:hover {
  transform: scale(1.05);
}

.brand-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: var(--radius-sm);
  color: white;
  transition: all 0.3s ease;
}

.navbar-brand:hover .brand-icon {
  transform: rotate(180deg);
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.brand-accent {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--dark);
  transition: all 0.3s ease;
}

.navbar-menu {
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

.nav-link {
  padding: 0.5rem 1rem;
  color: var(--dark-700);
  text-decoration: none;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all 0.3s ease;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: translateX(-50%);
  transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 80%;
}

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

.nav-cta {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-md);
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
  transition: all 0.3s ease;
}

.nav-cta::after {
  display: none;
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(99, 102, 241, 0.4);
  color: white;
}

/* HERO */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding-top: 80px;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  overflow: hidden;
}

.gradient-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.6;
  animation: float 20s ease-in-out infinite;
}

.orb-1 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.8), transparent);
  top: -200px;
  left: -200px;
  animation-delay: 0s;
}

.orb-2 {
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.8), transparent);
  top: 50%;
  right: -150px;
  animation-delay: 5s;
}

.orb-3 {
  width: 350px;
  height: 350px;
  background: radial-gradient(circle, rgba(236, 72, 153, 0.6), transparent);
  bottom: -100px;
  left: 30%;
  animation-delay: 10s;
}

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(50px, -50px) scale(1.1); }
  66% { transform: translate(-50px, 50px) scale(0.9); }
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1.25rem;
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 50px;
  color: white;
  font-weight: 500;
  font-size: 0.875rem;
  margin-bottom: var(--spacing-md);
  animation: slideIn 1s ease-out 0.2s backwards;
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

.badge-icon {
  font-size: 1.25rem;
}

.hero-title {
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 900;
  line-height: 1.1;
  margin-bottom: var(--spacing-md);
  color: white;
  animation: slideIn 1s ease-out 0.4s backwards;
}

.gradient-text {
  background: linear-gradient(135deg, #fff, #a5b4fc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  background-size: 200% auto;
  animation: shimmer 3s ease-in-out infinite;
}

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

.hero-subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  max-width: 600px;
  margin: 0 auto var(--spacing-xl);
  line-height: 1.8;
  animation: slideIn 1s ease-out 0.6s backwards;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: var(--spacing-xl);
  margin-top: var(--spacing-xl);
  animation: fadeInUp 1s ease-out 0.8s backwards;
}

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

.stat-number {
  font-size: 2rem;
  font-weight: 800;
  color: white;
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.7);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
  0%, 100% { transform: translate(-50%, 0); }
  50% { transform: translate(-50%, 10px); }
}

.mouse {
  width: 26px;
  height: 40px;
  border: 2px solid rgba(255, 255, 255, 0.5);
  border-radius: 13px;
  position: relative;
}

.wheel {
  width: 4px;
  height: 8px;
  background: rgba(255, 255, 255, 0.7);
  border-radius: 2px;
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  animation: scroll 1.5s ease-in-out infinite;
}

@keyframes scroll {
  0% { opacity: 1; transform: translate(-50%, 0); }
  100% { opacity: 0; transform: translate(-50%, 12px); }
}

/* SECTIONS */
main {
  background: linear-gradient(to bottom, transparent, var(--gray-lightest) 20%);
  position: relative;
  z-index: 1;
  padding-bottom: var(--spacing-2xl);
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.section-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: white;
  border-radius: 50px;
  font-weight: 600;
  font-size: 0.875rem;
  color: var(--primary);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-sm);
}

.section-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  margin-bottom: var(--spacing-sm);
  color: var(--dark);
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--gray);
  max-width: 600px;
  margin: 0 auto;
}

/* PAGE LAYOUT */
.page-header {
  padding-top: 110px;
  padding-bottom: var(--spacing-lg);
  text-align: center;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  margin-bottom: var(--spacing-sm);
}

.breadcrumb a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

.page-title {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-size: clamp(1.75rem, 4.5vw, 3rem);
  font-weight: 800;
  color: white;
}

.page-title svg {
  flex-shrink: 0;
}

.page-subtitle {
  font-size: 1.05rem;
  color: var(--gray);
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}

.page-content {
  padding-top: var(--spacing-lg);
  padding-bottom: var(--spacing-2xl);
}

.content-section {
  margin-top: var(--spacing-xl);
}

.content-section h2 {
  font-size: clamp(1.4rem, 3.5vw, 2.1rem);
  margin-bottom: var(--spacing-sm);
}

.content-section p {
  color: var(--dark-700);
  margin-bottom: var(--spacing-sm);
}

.tips-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-md);
}

.tip-card {
  background: white;
  border: 2px solid var(--gray-lighter);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
}

.tip-card h3 {
  margin-bottom: 0.5rem;
}

.ad-space {
  width: 100%;
  min-height: 120px;
  margin: var(--spacing-lg) 0;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.4);
  border: 1px dashed rgba(255, 255, 255, 0.5);
}

.content-section table {
  width: 100%;
  border-collapse: collapse;
}

.content-section th,
.content-section td {
  padding: 0.75rem;
  text-align: left;
  vertical-align: top;
}

/* CALCULATOR */
.calculator-section {
  padding: var(--spacing-xl) 0;
}

.calculator-card {
  background: white;
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-2xl);
  border: 1px solid var(--gray-lighter);
  position: relative;
  overflow: hidden;
  animation: scaleIn 0.5s ease-out;
}

@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}

.calculator-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary), var(--accent));
  background-size: 200% 100%;
  animation: shimmer 3s ease-in-out infinite;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.form-group {
  margin-bottom: var(--spacing-md);
}

label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: var(--dark-700);
  margin-bottom: var(--spacing-xs);
  font-size: 0.9375rem;
}

.label-icon {
  font-size: 1.25rem;
}

.input-group {
  display: flex;
  gap: 0.5rem;
  position: relative;
}

input[type="number"],
select {
  flex: 1;
  padding: 1rem;
  font-size: 1rem;
  border: 2px solid var(--gray-lighter);
  border-radius: var(--radius-md);
  font-family: inherit;
  background: white;
  color: var(--dark);
  transition: all 0.3s ease;
}

input[type="number"]:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
  transform: translateY(-2px);
}

.unit-select {
  min-width: 100px;
}

.input-suffix {
  position: absolute;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--gray);
  font-weight: 600;
  pointer-events: none;
}

.speed-presets-section {
  margin: var(--spacing-lg) 0;
}

.presets-label {
  font-size: 0.875rem;
  color: var(--gray);
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
}

.speed-presets {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 0.75rem;
}

.preset-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1rem;
  border: 2px solid var(--gray-lighter);
  background: white;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.3s ease;
  text-align: center;
}

.preset-btn:hover {
  border-color: var(--primary-light);
  background: rgba(99, 102, 241, 0.05);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.preset-btn.active {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  border-color: transparent;
  box-shadow: 0 8px 20px rgba(99, 102, 241, 0.3);
}

.preset-icon {
  font-size: 1.5rem;
  margin-bottom: 0.25rem;
}

.preset-name {
  font-weight: 600;
  font-size: 0.875rem;
  margin-bottom: 0.25rem;
}

.preset-speed {
  font-size: 0.75rem;
  opacity: 0.8;
}

.btn-calculate {
  width: 100%;
  padding: 1.25rem 2rem;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: 1.125rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 8px 25px rgba(99, 102, 241, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-top: var(--spacing-md);
}

.btn-calculate:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 35px rgba(99, 102, 241, 0.4);
}

.btn-calculate:active {
  transform: translateY(0);
}

.btn-icon {
  font-size: 1.5rem;
  transition: transform 0.3s ease;
}

.btn-calculate:hover .btn-icon {
  transform: translateX(5px);
}

/* RESULT */
.result {
  margin-top: var(--spacing-xl);
  padding: var(--spacing-lg);
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(139, 92, 246, 0.1));
  border: 2px solid rgba(99, 102, 241, 0.2);
  border-radius: var(--radius-lg);
  display: none;
  animation: slideInResult 0.5s ease-out;
}

@keyframes slideInResult {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.result.visible {
  display: block;
}

.result-header h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: var(--spacing-md);
}

.result-content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.result-main {
  padding: var(--spacing-md);
  background: white;
  border-radius: var(--radius-md);
}

.result-time {
  font-size: 2.5rem;
  font-weight: 900;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
}

.result-eta {
  color: var(--gray);
  font-size: 1rem;
}

.result-recommendation {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: var(--spacing-md);
  background: white;
  border-radius: var(--radius-md);
  border-left: 4px solid var(--success);
}

.rec-icon {
  font-size: 1.5rem;
}

.rec-text {
  font-weight: 600;
  color: var(--dark-700);
}

/* CARDS */
.popular-section {
  padding: var(--spacing-xl) 0;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.download-card {
  padding: var(--spacing-lg);
  background: white;
  border: 2px solid var(--gray-lighter);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: var(--dark);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.download-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 0;
  background: linear-gradient(180deg, var(--primary), var(--secondary));
  transition: height 0.3s ease;
}

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

.download-card:hover::before {
  height: 100%;
}

.card-icon {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-sm);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: var(--spacing-xs);
}

.card-description {
  color: var(--gray);
  font-size: 0.9375rem;
  line-height: 1.6;
  margin-bottom: var(--spacing-md);
}

.card-footer {
  margin-top: auto;
}

.card-link {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.9375rem;
  transition: all 0.3s ease;
}

.download-card:hover .card-link {
  transform: translateX(5px);
  display: inline-block;
}

/* FAQ */
.faq-section {
  padding: var(--spacing-xl) 0;
}

.faq-grid {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: white;
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-sm);
  overflow: hidden;
  border: 2px solid var(--gray-lighter);
  transition: all 0.3s ease;
}

.faq-item:hover {
  border-color: var(--primary-light);
}

.faq-question {
  width: 100%;
  padding: var(--spacing-md);
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  font-size: 1rem;
  color: var(--dark);
  transition: all 0.3s ease;
}

.faq-question:hover {
  background: rgba(99, 102, 241, 0.05);
}

.faq-icon {
  font-size: 1.5rem;
  color: var(--primary);
  transition: transform 0.3s ease;
  flex-shrink: 0;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 var(--spacing-md) var(--spacing-md);
}

.faq-answer p {
  color: var(--gray);
  line-height: 1.8;
  margin: 0;
}

/* CTA */
.cta-section {
  padding: var(--spacing-xl) 0;
}

.cta-card {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  color: white;
  box-shadow: var(--shadow-2xl);
  position: relative;
  overflow: hidden;
}

.cta-card::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.1), transparent);
  animation: rotate 20s linear infinite;
}

@keyframes rotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.cta-content {
  position: relative;
  z-index: 1;
  max-width: 600px;
}

.cta-title {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: var(--spacing-sm);
}

.cta-text {
  font-size: 1.125rem;
  margin-bottom: var(--spacing-lg);
  opacity: 0.9;
}

.cta-buttons {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.btn-primary,
.btn-secondary {
  padding: 0.875rem 1.75rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  display: inline-block;
}

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

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

.btn-secondary {
  background: rgba(255, 255, 255, 0.2);
  color: white;
  border: 2px solid white;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.3);
}

/* FOOTER */
.footer {
  background: var(--dark);
  color: var(--gray-light);
  padding: var(--spacing-2xl) 0 var(--spacing-md);
  margin-top: var(--spacing-2xl);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: var(--spacing-sm);
}

.footer-brand .brand-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: white;
}

.footer-description {
  color: var(--gray);
  line-height: 1.8;
}

.footer-column h4 {
  color: white;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
}

.footer-column a {
  display: block;
  color: var(--gray);
  text-decoration: none;
  margin-bottom: 0.5rem;
  transition: all 0.3s ease;
}

.footer-column a:hover {
  color: white;
  transform: translateX(5px);
}

.footer-bottom {
  border-top: 1px solid var(--dark-700);
  padding-top: var(--spacing-md);
  text-align: center;
}

.footer-bottom p {
  color: var(--gray);
  font-size: 0.875rem;
  margin: 0.25rem 0;
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .mobile-toggle {
    display: flex;
  }
  
  .navbar-menu {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    padding: var(--spacing-md);
    box-shadow: var(--shadow-xl);
    transform: translateY(-100%);
    opacity: 0;
    transition: all 0.3s ease;
    max-height: calc(100vh - 70px);
    overflow-y: auto;
  }
  
  .navbar-menu.active {
    transform: translateY(0);
    opacity: 1;
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .speed-presets {
    grid-template-columns: 1fr 1fr;
  }

  .page-header {
    padding-top: 90px;
  }

  .page-title svg {
    width: 32px;
    height: 32px;
  }

  .page-content {
    padding-top: var(--spacing-md);
  }

  .content-section {
    margin-top: var(--spacing-lg);
  }

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

  .calculator-card {
    padding: var(--spacing-lg);
  }

  .content-section table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }

  .content-section th,
  .content-section td {
    white-space: nowrap;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .cards-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .container {
    padding-left: var(--spacing-sm);
    padding-right: var(--spacing-sm);
  }

  .input-group {
    flex-direction: column;
    align-items: stretch;
  }

  .unit-select {
    width: 100%;
    min-width: 0;
  }

  .hero-title {
    font-size: 2rem;
  }
  
  .section-title {
    font-size: 1.75rem;
  }

  .page-title {
    font-size: 1.5rem;
  }

  .page-title svg {
    width: 28px;
    height: 28px;
  }

  .speed-presets {
    grid-template-columns: 1fr;
  }

  .result-time {
    font-size: 1.9rem;
  }

  .btn-calculate {
    font-size: 1rem;
    padding: 1rem 1.25rem;
  }
}

/* Auto-Detect Speed Button Styles */
.btn-auto-detect {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: linear-gradient(135deg, #8b5cf6, #6366f1);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
  white-space: nowrap;
  min-height: 48px;
}

.btn-auto-detect:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(139, 92, 246, 0.4);
}

.btn-auto-detect:active {
  transform: translateY(0);
}

.btn-auto-detect:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.btn-auto-detect svg {
  flex-shrink: 0;
}

.btn-auto-detect.loading svg {
  animation: spin 1s linear infinite;
}

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

/* Responsive adjustments */
@media (max-width: 768px) {
  .btn-auto-detect .btn-auto-text {
    display: none;
  }
  
  .btn-auto-detect {
    padding: 0.75rem;
    min-width: 48px;
    justify-content: center;
  }
}