/* ===========================
   Design Tokens
   =========================== */
:root {
  --bg-primary: #0d0d0d;
  --bg-secondary: #111111;
  --text-primary: #ffffff;
  --text-secondary: rgba(255, 255, 255, 0.85);
  --text-muted: rgba(255, 255, 255, 0.65);
  --accent-gold: #c8a84b;
  --accent-gold-hover: #d4b55e;
  --font-korean: 'Noto Sans KR', sans-serif;
  --font-english: 'Inter', sans-serif;
  --section-padding: 120px 60px;
  --max-width: 900px;
  --border-radius-btn: 999px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-korean);
  line-height: 1.7;
  overflow-x: hidden;
}

::-webkit-scrollbar {
  display: none;
}


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

/* ===========================
   Sticky CTA Button
   =========================== */
.sticky-cta {
  position: fixed;
  bottom: 32px;
  right: 32px;
  z-index: 1000;
  background-color: var(--accent-gold);
  color: #000;
  font-family: var(--font-korean);
  font-size: 14px;
  font-weight: 600;
  padding: 12px 22px;
  border-radius: var(--border-radius-btn);
  transition: background-color 0.2s ease, transform 0.2s ease, opacity 0.4s ease-out;
  letter-spacing: 0.02em;
  overflow: hidden;
}

.sticky-cta:hover {
  background-color: var(--accent-gold-hover);
  transform: scale(1.05);
}

/* ===========================
   Navigation
   =========================== */
.navbar {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 4% 0 0 0;
  transition: all 0.3s ease;
}

.nav-logo {
  width: 40px;
  display: flex;
  align-items: center;
  opacity: 0.9;
  transition: opacity 0.2s, transform 0.3s;
  animation: fadeInDown 0.8s ease-out;
}

.nav-logo:hover {
  opacity: 1;
  transform: scale(1.1);
}

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

/* ===========================
   Hero Section
   =========================== */
.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 50px 10% 60px 150px;
}

.hero-content {
  max-width: 600px;
}

.hero-subtitle {
  font-family: var(--font-english);
  font-size: 35px;
  font-weight: lighter;
  color: var(--text-secondary);
  margin-left: 5px;
  letter-spacing: 0.02em;
  animation: fadeInUp 0.8s ease-out 0.1s both;
}

.hero-title {
  font-family: var(--font-english);
  font-size: clamp(80px, 14vw, 160px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 20px;
  color: var(--text-primary);
  animation: titleReveal 1s ease-out;
}

.hero-desc {
  font-family: var(--font-korean);
  font-size: 18px;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 0.01em;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.scroll-indicator {
  position: absolute;
  bottom: -60px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-english);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: #f0f0f0;
  text-transform: uppercase;
  animation: scrollBounce 2s ease-in-out infinite;
  margin-bottom: 60px;
}

@keyframes scrollBounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

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

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

/* ===========================
   Common Animation Classes
   =========================== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

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

/* ===========================
   Introduction Section
   =========================== */
.intro-section {
  padding: var(--section-padding);
  max-width: 1100px;
  margin: 500px auto;
}

.intro-title {
  font-family: var(--font-korean);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 36px;
  letter-spacing: -0.01em;
}

.intro-text p {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.8;
  font-weight: 400;
}

/* ===========================
   Platform Dev Section
   =========================== */
.platform-section {
  padding: var(--section-padding);
  max-width: 1100px;
  margin: 0 auto;
}

.platform-title {
  font-family: var(--font-korean);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 36px;
  letter-spacing: -0.01em;
}

.platform-text p {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.8;
  font-weight: 400;
}

/* ===========================
   Projects Section
   =========================== */
.projects-section {
  padding: var(--section-padding);
  max-width: 1100px;
  margin: 0 auto;
}

.projects-title {
  font-family: var(--font-english);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 48px;
  letter-spacing: -0.01em;
}

.projects-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.project-card {
  cursor: pointer;
  transition: all 0.3s ease;
}

.project-card:hover {
  transform: translateY(-12px);
}

.project-image {  
  width: 100%;
  height: 80%;
  border-radius: 20px;
  object-fit: cover;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:hover .project-image {
  transform: scale(1.02);
  box-shadow: 0 20px 40px rgba(204, 173, 81, 0.204);
}

.project-info h3 {
  font-family: var(--font-english);
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
  letter-spacing: -0.01em;
}

.project-info p {
  font-size: 14px;
  color: var(--text-secondary);
  font-weight: 400;
}

/* ===========================
   Advantage Section
   =========================== */
.advantage-section {
  padding: var(--section-padding);
  max-width: 1100px;
  margin: 0 auto;
}

.advantage-title {
  font-family: var(--font-english);
  font-size: clamp(60px, 10vw, 100px);
  font-weight: 800;
  color: rgba(255, 255, 255, 0.15);
  letter-spacing: -0.03em;
  margin-bottom: 80px;
  line-height: 1;
}

.advantage-list {
  display: flex;
  flex-direction: column;
  gap: 80px;
}

.advantage-item {
  display: block;
  max-width: 1200px;
}

.advantage-content h3 {
  font-family: var(--font-korean);
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}

.advantage-content p {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 14px;
  line-height: 1.8;
  font-weight: 400;
}

/* ===========================
   Tech Stack Section
   =========================== */
.tech-section {
  position: relative;
  min-height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: 80px 40px;
}

.tech-floating-icons {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.tech-icon {
  position: absolute;
  opacity: 0.85;
  filter: drop-shadow(0 4px 20px rgba(0,0,0,0.5));
  animation: float 6s ease-in-out infinite;
}

.tech-react {
  left: 10%;
  top: 20%;
  animation-delay: 0s;
  animation-duration: 7s;
}

.tech-docker {
  left: 55%;
  top: 3%;
  animation-delay: -1.5s;
  animation-duration: 8s;
}

.tech-nextjs {
  right: 12%;
  top: 35%;
  animation-delay: -3s;
  animation-duration: 6.5s;
}

.tech-typescript {
  left: 18%;
  bottom: 20%;
  animation-delay: -2s;
  animation-duration: 7.5s;
}

.tech-nestjs {
  right: 18%;
  bottom: 15%;
  animation-delay: -4s;
  animation-duration: 6s;
}

.tech-spring {
  left: 38%;
  top: 12%;
  animation-delay: -0.5s;
  animation-duration: 9s;
}

.tech-kotlin {
  right: 5%;
  top: 15%;
  animation-delay: -2.5s;
  animation-duration: 7s;
}

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  33% { transform: translateY(-15px) rotate(3deg); }
  66% { transform: translateY(8px) rotate(-2deg); }
}

.tech-cta {
  position: relative;
  z-index: 10;
  text-align: center;
  animation: fadeInUp 0.8s ease-out;
}

.tech-cta h2 {
  font-family: var(--font-korean);
  font-size: clamp(20px, 3vw, 28px);
  font-weight: 400;
  color: var(--text-primary);
  line-height: 1.6;
  margin-bottom: 4px;
}

.tech-cta h2 strong {
  font-weight: 700;
}

.cta-button {
  display: inline-block;
  margin-top: 32px;
  background-color: var(--accent-gold);
  color: #000;
  font-family: var(--font-korean);
  font-size: 15px;
  font-weight: 600;
  padding: 14px 28px;
  border-radius: var(--border-radius-btn);
  transition: background-color 0.2s ease, transform 0.2s ease;
  letter-spacing: 0.02em;
  position: relative;
  overflow: hidden;
}

.cta-button::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  pointer-events: none;
}

.cta-button:hover {
  background-color: var(--accent-gold-hover);
  transform: scale(1.05);
}

.cta-button:hover::before {
  animation: buttonRipple 0.6s ease-out;
}

/* ===========================
   Footer
   =========================== */
.footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 32px 60px;
  border-top: 1px solid rgba(255,255,255,0.06);
  animation: fadeInUp 0.8s ease-out;
}

.footer-logo {
  opacity: 0.7;
  transition: opacity 0.2s, transform 0.3s;
}

.footer-logo:hover {
  opacity: 1;
  transform: scale(1.1);
}

.footer-links {
  display: flex;
  gap: 32px;
}

.footer-links a {
  font-family: var(--font-english);
  font-size: 15px;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 0.02em;
  transition: color 0.2s, transform 0.2s;
  position: relative;
}

.footer-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-gold);
  transition: width 0.3s ease;
}

.footer-links a:hover {
  color: var(--text-primary);
  transform: translateY(-2px);
}

.footer-links a:hover::after {
  width: 100%;
}

/* ===========================
   Responsive
   =========================== */
@media (max-width: 768px) {
  :root {
    --section-padding: 80px 24px;
  }

  .hero {
    padding: 80px 24px 60px;
  }

  .hero-title {
    font-size: clamp(60px, 18vw, 100px);
  }

  .intro-container {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .intro-label {
    position: static;
  }

  .projects-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .advantage-item {
    grid-template-columns: 50px 1fr;
    margin-left: 0;
  }

  .tech-icon {
    transform: scale(0.7);
  }

  .footer {
    padding: 24px;
    flex-direction: column;
    gap: 16px;
  }

  .sticky-cta {
    bottom: 20px;
    right: 20px;
    font-size: 13px;
    padding: 10px 18px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 64px;
  }

  .advantage-title {
    font-size: 48px;
  }

  .tech-floating-icons {
    opacity: 0.5;
  }
}