/* ============================================
   Sip - Landing Page Styles
   "Liquid Intelligence" Theme
   ============================================ */

/* CSS Variables */
:root {
  --color-primary-dark: #00695C;
  --color-primary: #00897B;
  --color-accent: #4DD0E1;
  --color-accent-light: #B2EBF2;
  --color-gradient-start: #00695C;
  --color-gradient-end: #4DD0E1;
  --color-text: #1A1A2E;
  --color-text-secondary: #64748B;
  --color-text-light: #94A3B8;
  --color-bg: #FFFFFF;
  --color-bg-secondary: #F8FAFC;
  --color-bg-gradient: linear-gradient(135deg, #F0FDFA 0%, #E0F2FE 100%);
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--color-text);
  line-height: 1.6;
  background: var(--color-bg);
  overflow-x: hidden;
}

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

a {
  color: inherit;
  text-decoration: none;
}

/* ============================================
   Animations
   ============================================ */

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

@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px rgba(77, 208, 225, 0.4); }
  50% { box-shadow: 0 0 40px rgba(77, 208, 225, 0.8); }
}

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

@keyframes fade-in-up {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes wave {
  0%, 100% { transform: translateX(0) translateY(0); }
  25% { transform: translateX(-5px) translateY(5px); }
  50% { transform: translateX(0) translateY(10px); }
  75% { transform: translateX(5px) translateY(5px); }
}

.animate-float {
  animation: float 6s ease-in-out infinite;
}

.animate-pulse-glow {
  animation: pulse-glow 3s ease-in-out infinite;
}

.animate-fade-in-up {
  animation: fade-in-up 0.6s ease-out forwards;
}

/* ============================================
   Layout
   ============================================ */

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

.section {
  padding: 80px 0;
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }
}

/* ============================================
   Header
   ============================================ */

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-primary-dark);
}

.logo-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color 0.2s;
}

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

.language-switcher {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
}

.lang-link {
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  color: var(--color-text-light);
  transition: all 0.2s;
}

.lang-link:hover {
  color: var(--color-text);
}

.lang-link.active {
  background: var(--color-primary);
  color: white;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--color-text);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .mobile-menu-btn {
    display: block;
  }
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 64px;
  overflow: hidden;
  background: var(--color-bg-gradient);
}

.hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.hero-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.5;
}

.hero-blob-1 {
  width: 600px;
  height: 600px;
  background: var(--color-accent);
  top: -200px;
  right: -100px;
  animation: wave 20s ease-in-out infinite;
}

.hero-blob-2 {
  width: 400px;
  height: 400px;
  background: var(--color-primary);
  bottom: -100px;
  left: -100px;
  animation: wave 15s ease-in-out infinite reverse;
}

.hero-content {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.hero-text {
  max-width: 560px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.8);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-primary-dark);
  margin-bottom: 24px;
  backdrop-filter: blur(10px);
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 50%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-phone {
  position: relative;
  width: 280px;
  height: 560px;
  background: linear-gradient(145deg, #1a1a2e 0%, #16213e 100%);
  border-radius: 40px;
  padding: 8px;
  box-shadow: 
    0 50px 100px -20px rgba(0, 105, 92, 0.3),
    0 30px 60px -30px rgba(0, 0, 0, 0.5);
  transform: perspective(1000px) rotateY(-15deg) rotateX(5deg);
  transition: transform 0.5s ease;
}

.hero-phone:hover {
  transform: perspective(1000px) rotateY(-5deg) rotateX(2deg);
}

.hero-phone-screen {
  width: 100%;
  height: 100%;
  border-radius: 32px;
  overflow: hidden;
  background: white;
}

.hero-phone-screen img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-glow {
  position: absolute;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, var(--color-accent) 0%, transparent 70%);
  opacity: 0.4;
  filter: blur(60px);
  z-index: -1;
}

@media (max-width: 968px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-text {
    max-width: 100%;
    order: 2;
  }
  
  .hero-visual {
    order: 1;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-phone {
    width: 220px;
    height: 440px;
  }
  
  .hero-cta {
    justify-content: center;
  }
}

/* ============================================
   Buttons
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: white;
  box-shadow: 0 4px 15px rgba(0, 105, 92, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0, 105, 92, 0.4);
}

.btn-secondary {
  background: white;
  color: var(--color-text);
  border: 2px solid #E2E8F0;
}

.btn-secondary:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-large {
  padding: 16px 32px;
  font-size: 1.1rem;
}

/* ============================================
   Features Section
   ============================================ */

.features {
  background: var(--color-bg);
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 64px;
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.feature-card {
  background: var(--color-bg-secondary);
  border-radius: var(--radius-xl);
  padding: 32px;
  transition: all 0.3s ease;
  border: 1px solid transparent;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-accent-light);
}

.feature-icon {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-accent-light) 0%, white 100%);
  border-radius: var(--radius-lg);
  color: var(--color-primary-dark);
  margin-bottom: 20px;
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

@media (max-width: 968px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  .section-title {
    font-size: 2rem;
  }
}

/* ============================================
   BHI Section
   ============================================ */

.bhi-section {
  background: var(--color-bg-gradient);
  position: relative;
  overflow: hidden;
}

.bhi-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.bhi-visual {
  position: relative;
}

.bhi-chart {
  background: white;
  border-radius: var(--radius-xl);
  padding: 32px;
  box-shadow: var(--shadow-xl);
}

.bhi-bar {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.bhi-bar-label {
  width: 80px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text);
}

.bhi-bar-track {
  flex: 1;
  height: 32px;
  background: #F1F5F9;
  border-radius: var(--radius-full);
  overflow: hidden;
  position: relative;
}

.bhi-bar-fill {
  height: 100%;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding-right: 12px;
  font-size: 0.8rem;
  font-weight: 600;
  color: white;
  transition: width 1s ease;
}

.bhi-bar-fill.high {
  background: linear-gradient(90deg, #10B981 0%, #34D399 100%);
}

.bhi-bar-fill.medium {
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-accent) 100%);
}

.bhi-bar-fill.low {
  background: linear-gradient(90deg, #F59E0B 0%, #FBBF24 100%);
}

.bhi-bar-fill.very-low {
  background: linear-gradient(90deg, #EF4444 0%, #F87171 100%);
}

.bhi-text {
  max-width: 480px;
}

.bhi-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
}

.bhi-desc {
  font-size: 1rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
}

.bhi-features {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.bhi-feature {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.bhi-feature-icon {
  width: 24px;
  height: 24px;
  color: var(--color-primary);
  flex-shrink: 0;
}

.bhi-feature-text {
  font-size: 0.95rem;
  color: var(--color-text);
}

@media (max-width: 968px) {
  .bhi-content {
    grid-template-columns: 1fr;
  }
  
  .bhi-text {
    max-width: 100%;
    order: 1;
  }
  
  .bhi-visual {
    order: 2;
  }
}

/* ============================================
   Screenshots Section
   ============================================ */

.screenshots {
  background: var(--color-bg);
}

.screenshots-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.screenshot-card {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: linear-gradient(145deg, #F8FAFC 0%, #F1F5F9 100%);
  padding: 16px;
  transition: all 0.4s ease;
}

.screenshot-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
}

.screenshot-frame {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #1a1a2e;
  padding: 8px;
  aspect-ratio: 9/19;
}

.screenshot-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius-md);
}

.screenshot-label {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 16px;
  background: linear-gradient(to top, rgba(0,0,0,0.8) 0%, transparent 100%);
  color: white;
  font-size: 0.9rem;
  font-weight: 500;
}

@media (max-width: 968px) {
  .screenshots-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .screenshots-grid {
    grid-template-columns: 1fr;
    max-width: 300px;
    margin: 0 auto;
  }
}

/* ============================================
   How It Works Section
   ============================================ */

.how-it-works {
  background: var(--color-bg-secondary);
}

.steps {
  display: flex;
  flex-direction: column;
  gap: 32px;
  max-width: 800px;
  margin: 0 auto;
}

.step {
  display: flex;
  gap: 24px;
  align-items: flex-start;
}

.step-number {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: white;
  font-size: 1.5rem;
  font-weight: 700;
  border-radius: var(--radius-lg);
  flex-shrink: 0;
}

.step-content {
  flex: 1;
  background: white;
  padding: 24px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
}

.step-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 8px;
}

.step-desc {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

@media (max-width: 640px) {
  .step {
    flex-direction: column;
    gap: 16px;
  }
}

/* ============================================
   FAQ Section
   ============================================ */

.faq {
  background: var(--color-bg);
}

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

.faq-item {
  border-bottom: 1px solid #E2E8F0;
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-text);
  transition: color 0.2s;
}

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

.faq-icon {
  width: 24px;
  height: 24px;
  transition: transform 0.3s;
  flex-shrink: 0;
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.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-bottom: 24px;
}

.faq-answer p {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

/* ============================================
   Contact Section
   ============================================ */

.contact {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: white;
  text-align: center;
}

.contact-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.contact-desc {
  font-size: 1.1rem;
  opacity: 0.9;
  margin-bottom: 32px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

.contact-email {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 16px 32px;
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-full);
  font-size: 1.1rem;
  font-weight: 500;
  transition: all 0.3s;
}

.contact-email:hover {
  background: rgba(255, 255, 255, 0.25);
  transform: translateY(-2px);
}

/* ============================================
   Footer
   ============================================ */

.footer {
  background: #0F172A;
  color: #94A3B8;
  padding: 64px 0 32px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand {
  max-width: 300px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: white;
  margin-bottom: 16px;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: white;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-link {
  font-size: 0.9rem;
  transition: color 0.2s;
}

.footer-link:hover {
  color: white;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.875rem;
}

@media (max-width: 968px) {
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .footer-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}

/* ============================================
   Utility Classes
   ============================================ */

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

.glass {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* Scroll animations */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}