/* Reset and base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary-color: #6366f1;
  --primary-dark: #4f46e5;
  --secondary-color: #f59e0b;
  --accent-color: #10b981;
  --background-color: #f8fafc;
  --surface-color: #ffffff;
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --text-light: #9ca3af;
  --border-color: #e5e7eb;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --gradient-warm: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
}

body {
  font-family: "Noto Sans KR", "Inter", sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--background-color);
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  z-index: 1000;
  transition: all 0.3s ease;
}

.nav {
  padding: 1rem 0;
}

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

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-menu {
  display: flex;
  gap: 2rem;
}

.nav-link {
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

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

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: width 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  cursor: pointer;
  padding: 0.5rem;
}

.mobile-menu-toggle span {
  width: 25px;
  height: 3px;
  background: var(--primary-color);
  margin: 2px 0;
  transition: 0.3s;
  border-radius: 2px;
}

.mobile-menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

/* Mobile Menu */
.mobile-menu {
  display: none;
  position: fixed;
  top: 80px;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(10px);
  z-index: 999;
  transform: translateY(-100%);
  transition: transform 0.3s ease;
}

.mobile-menu.active {
  transform: translateY(0);
}

.mobile-menu-content {
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.mobile-nav-link {
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 500;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border-color);
  transition: color 0.3s ease;
}

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

.mobile-nav-link:last-child {
  border-bottom: none;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  position: relative;
  z-index: 2;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.hero-title .highlight {
  background: linear-gradient(45deg, #ffd700, #ffed4e);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.9;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  padding: 1rem 2rem;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
  font-size: 1rem;
}

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

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

.btn-secondary {
  background: rgba(255, 255, 255, 0.1);
  color: white;
  border: 2px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

/* Phone Mockup */
.phone-mockup {
  position: relative;
  width: 300px;
  height: 600px;
  margin: 0 auto;
  background: #000;
  border-radius: 40px;
  padding: 8px;
  box-shadow: var(--shadow-xl);
}

.phone-screen {
  width: 100%;
  height: 100%;
  background: var(--surface-color);
  border-radius: 32px;
  overflow: hidden;
  position: relative;
}

.app-interface {
  height: 100%;
  display: flex;
  flex-direction: column;
}

.interface-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  background: var(--background-color);
  color: var(--text-primary);
}

.time {
  font-weight: 600;
}

.status-icons {
  display: flex;
  gap: 0.5rem;
}

.interface-content {
  flex: 1;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.chat-message {
  margin-bottom: 1rem;
  padding: 0.75rem;
  border-radius: 18px;
  max-width: 80%;
}

.chat-message.ai {
  background: var(--gradient-primary);
  color: white;
  align-self: flex-start;
}

.chat-message.user {
  background: var(--border-color);
  color: var(--text-primary);
  align-self: flex-end;
}

.chat-input {
  display: flex;
  gap: 0.5rem;
  padding: 0.5rem;
  background: var(--background-color);
  border-radius: 25px;
}

.chat-input input {
  flex: 1;
  border: none;
  background: none;
  padding: 0.5rem;
  outline: none;
}

.chat-input button {
  background: var(--primary-color);
  color: white;
  border: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
}

/* Hero Background */
.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
}

.gradient-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(40px);
  opacity: 0.3;
  animation: float 6s ease-in-out infinite;
}

.orb-1 {
  width: 400px;
  height: 400px;
  background: var(--gradient-accent);
  top: -200px;
  right: -200px;
  animation-delay: 0s;
}

.orb-2 {
  width: 300px;
  height: 300px;
  background: var(--gradient-secondary);
  bottom: -150px;
  left: -150px;
  animation-delay: 2s;
}

.orb-3 {
  width: 200px;
  height: 200px;
  background: var(--gradient-warm);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  animation-delay: 4s;
}

@keyframes float {
  0%,
  100% {
    transform: translate(0, 0) rotate(0deg);
  }
  33% {
    transform: translate(30px, -30px) rotate(120deg);
  }
  66% {
    transform: translate(-20px, 20px) rotate(240deg);
  }
}

/* Features Section */
.features {
  padding: 6rem 0;
  background: var(--surface-color);
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: var(--surface-color);
  padding: 2rem;
  border-radius: 20px;
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  border: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

.feature-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;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

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

.feature-card.featured {
  background: var(--gradient-primary);
  color: white;
}

.feature-card.featured .feature-description {
  color: rgba(255, 255, 255, 0.9);
}

.feature-icon {
  width: 60px;
  height: 60px;
  background: var(--gradient-accent);
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
  color: white;
}

.feature-card.featured .feature-icon {
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
}

.feature-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.feature-description {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.6;
}

.feature-highlight {
  padding: 0.5rem 1rem;
  background: var(--gradient-warm);
  border-radius: 25px;
  display: inline-block;
}

.highlight-text {
  color: white;
  font-weight: 500;
  font-size: 0.9rem;
}

.feature-card.featured .feature-highlight {
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
}

/* How It Works Section */
.how-it-works {
  padding: 6rem 0;
  background: var(--background-color);
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 3rem;
  margin-top: 3rem;
}

.step {
  text-align: center;
  position: relative;
}

.step-number {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  font-weight: 700;
  color: white;
  margin: 0 auto 1.5rem;
  box-shadow: var(--shadow-lg);
}

.step h3 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.step p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Download Section */
.download {
  padding: 6rem 0;
  background: var(--gradient-primary);
  color: white;
}

.download-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.download-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.download-subtitle {
  font-size: 1.2rem;
  margin-bottom: 2rem;
  opacity: 0.9;
  line-height: 1.6;
}

.download-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.download-btn {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1rem 1.5rem;
  background: rgba(255, 255, 255, 0.1);
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-radius: 15px;
  text-decoration: none;
  color: white;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.download-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-2px);
}

.download-btn i {
  font-size: 2rem;
}

.download-btn div {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.download-btn span {
  font-size: 0.9rem;
  opacity: 0.8;
}

.download-btn strong {
  font-size: 1.1rem;
  font-weight: 600;
}

.phone-preview {
  width: 250px;
  height: 500px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 30px;
  margin: 0 auto;
  backdrop-filter: blur(10px);
  border: 2px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
}

.preview-screen {
  width: 80%;
  height: 80%;
  background: var(--surface-color);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--text-primary);
}

/* Footer */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 3rem 0 1rem;
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 3rem;
  margin-bottom: 2rem;
}

.footer-brand h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.footer-brand p {
  opacity: 0.8;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.footer-column h4 {
  margin-bottom: 1rem;
  font-weight: 600;
}

.footer-column a {
  display: block;
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  margin-bottom: 0.5rem;
  transition: color 0.3s ease;
}

.footer-column a:hover {
  color: white;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 1rem;
  text-align: center;
  opacity: 0.8;
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 2rem;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .nav-menu {
    display: none;
  }

  .mobile-menu-toggle {
    display: flex;
  }

  .mobile-menu {
    display: block;
  }

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

  .download-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer-links {
    grid-template-columns: 1fr;
  }

  .phone-mockup {
    width: 250px;
    height: 500px;
  }

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

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }

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

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

  .btn {
    padding: 0.8rem 1.5rem;
    font-size: 0.9rem;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .download-buttons {
    flex-direction: column;
    align-items: center;
  }
}

/* Animation Classes */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.slide-in-left {
  opacity: 0;
  transform: translateX(-50px);
  transition: all 0.6s ease;
}

.slide-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.slide-in-right {
  opacity: 0;
  transform: translateX(50px);
  transition: all 0.6s ease;
}

.slide-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

/* Loading Spinner */
.loading-spinner {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 10000;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loading-spinner.hidden {
  opacity: 0;
  visibility: hidden;
}

.spinner {
  width: 60px;
  height: 60px;
  margin-bottom: 2rem;
}

.spinner-inner {
  position: relative;
  width: 100%;
  height: 100%;
}

.spinner-circle {
  position: absolute;
  width: 20px;
  height: 20px;
  background: white;
  border-radius: 50%;
  animation: spinner-bounce 1.4s ease-in-out infinite both;
}

.spinner-circle:nth-child(1) {
  top: 0;
  left: 20px;
  animation-delay: -0.32s;
}

.spinner-circle:nth-child(2) {
  top: 20px;
  left: 40px;
  animation-delay: -0.16s;
}

.spinner-circle:nth-child(3) {
  top: 40px;
  left: 20px;
  animation-delay: 0s;
}

@keyframes spinner-bounce {
  0%,
  80%,
  100% {
    transform: scale(0);
  }
  40% {
    transform: scale(1);
  }
}

.loading-text {
  color: white;
  font-size: 1.2rem;
  font-weight: 500;
  margin: 0;
  opacity: 0.9;
}