/* =====================================================
   Klipsan-Style Portfolio - Modern Dark Theme
   Color: Monotone + Blue accent
   ===================================================== */

/* Google Fonts — loaded via <link> in HTML for performance */

/* CSS Custom Properties (Design Tokens) */
:root {
  /* Colors - Light Theme */
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-primary-dark: #1d4ed8;

  --color-bg: #ffffff;
  --color-surface: #f8fafc;
  --color-surface-light: #f1f5f9;
  --color-border: #e2e8f0;

  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;

  --color-accent: #2563eb;
  --color-success: #22c55e;
  --color-warning: #f59e0b;

  /* Typography */
  --font-sans: 'Pretendard', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Spacing */
  --section-padding: clamp(4rem, 10vh, 8rem);
  --container-max: 1200px;
  --container-padding: clamp(1rem, 5vw, 2rem);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;

  /* Shadows */
  --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);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Selection */
::selection {
  background-color: var(--color-primary);
  color: var(--color-text);
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--color-surface-light);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-primary);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text);
}

h1 { font-size: clamp(2.5rem, 6vw, 4rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.75rem); }
h4 { font-size: clamp(1rem, 2vw, 1.25rem); }

p {
  color: var(--color-text-secondary);
  font-size: 1rem;
  line-height: 1.8;
}

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary);
}

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

/* Container */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Section */
.section {
  padding: var(--section-padding) 0;
  position: relative;
}

.section--alt {
  background-color: var(--color-surface);
}

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

.section__title {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 1rem;
  position: relative;
  display: inline-block;
}

.section__title::after {
  content: '';
  position: absolute;
  bottom: -0.5rem;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  border-radius: 2px;
}

.section__subtitle {
  color: var(--color-text-muted);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* =====================================================
   NAVBAR
   ===================================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 1rem 0;
  transition: all var(--transition-base);
  background: transparent;
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  padding: 0.75rem 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.navbar__container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.navbar__brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  opacity: 0;
  transform: translateY(-10px);
  transition: all var(--transition-base);
}

.navbar.scrolled .navbar__brand {
  opacity: 1;
  transform: translateY(0);
}

.navbar__menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.navbar__link {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  line-height: 1;
  transition: color var(--transition-fast);
  position: relative;
}

.navbar__link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition-base);
}

.navbar__link:hover,
.navbar__link.active {
  color: var(--color-text);
}

.navbar__link:hover::after,
.navbar__link.active::after {
  width: 100%;
}

/* Dropdown Menu */
.navbar__dropdown {
  position: relative;
}

.navbar__link--dropdown {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  line-height: 1;
}

.navbar__link--dropdown i {
  font-size: 0.625rem;
  transition: transform var(--transition-fast);
}

.navbar__dropdown:hover .navbar__link--dropdown i {
  transform: rotate(180deg);
}

.navbar__dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  min-width: 160px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 0.5rem 0;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
  z-index: 1000;
  list-style: none;
}

.navbar__dropdown:hover .navbar__dropdown-menu {
  opacity: 1;
  visibility: visible;
}

.navbar__dropdown-link {
  display: block;
  padding: 0.5rem 1rem;
  color: var(--color-text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition-fast);
}

.navbar__dropdown-link:hover {
  color: var(--color-primary);
  background: rgba(99, 102, 241, 0.1);
}

.navbar__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.navbar__toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: all var(--transition-fast);
}

@media (max-width: 768px) {
  .navbar__toggle {
    display: flex;
  }

  .navbar__menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--color-surface);
    flex-direction: column;
    padding: 5rem 2rem;
    gap: 1.5rem;
    transition: right var(--transition-base);
    box-shadow: -10px 0 30px rgba(0, 0, 0, 0.15);
  }

  .navbar__menu.open {
    right: 0;
  }

  .navbar__toggle.open span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }

  .navbar__toggle.open span:nth-child(2) {
    opacity: 0;
  }

  .navbar__toggle.open span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  /* Mobile Dropdown */
  .navbar__dropdown-menu {
    position: static;
    transform: none;
    min-width: auto;
    background: transparent;
    border: none;
    border-left: 2px solid var(--color-border);
    border-radius: 0;
    padding: 0.5rem 0 0.5rem 1rem;
    margin-top: 0.5rem;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
  }

  .navbar__dropdown-link {
    padding: 0.4rem 0;
  }

  .navbar__link--dropdown i {
    display: none;
  }
}

/* =====================================================
   HERO SECTION
   ===================================================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #ffffff 0%, #f8fafc 50%, #ffffff 100%);
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(37, 99, 235, 0.15) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 20%, rgba(59, 130, 246, 0.1) 0%, transparent 40%),
    radial-gradient(ellipse at 60% 80%, rgba(37, 99, 235, 0.08) 0%, transparent 40%);
  pointer-events: none;
}

/* Grid pattern overlay */
.hero::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image:
    linear-gradient(rgba(0, 0, 0, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 0, 0, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
  pointer-events: none;
}

.hero__content {
  text-align: center;
  z-index: 1;
  padding: 0 var(--container-padding);
}

.hero__greeting {
  font-size: 1rem;
  color: var(--color-primary-light);
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 1rem;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 0.2s;
}

.hero__name {
  font-size: clamp(3rem, 10vw, 6rem);
  font-weight: 700;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 0.4s;
}

.hero__title {
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: 600;
  color: var(--color-primary-light);
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 0.6s;
}

.hero__description {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto 2.5rem;
  line-height: 1.8;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 0.8s;
}

.hero__social {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 3rem;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 1s;
}

.hero__social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 1.25rem;
  transition: all var(--transition-base);
  border: 1px solid transparent;
}

.hero__social-link:hover {
  background: var(--color-primary);
  transform: translateY(-4px);
  border-color: var(--color-primary-light);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.3);
}

.hero__scroll {
  position: absolute;
  bottom: 2rem;
  left: 47%;
  transform: translateX(-53%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  cursor: pointer;
  opacity: 0;
  animation: fadeInUp 0.8s ease forwards;
  animation-delay: 1.2s;
  transition: color var(--transition-fast);
}

.hero__scroll:hover {
  color: var(--color-primary-light);
}

.hero__scroll-icon {
  width: 24px;
  height: 50px;
  border: 2px solid currentColor;
  border-radius: 12px;
  position: relative;
}

.hero__scroll-icon::before {
  content: '';
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  background: currentColor;
  border-radius: 2px;
  animation: scrollDown 1.5s ease-in-out infinite;
}

@keyframes scrollDown {
  0% { opacity: 1; transform: translateX(-50%) translateY(0); }
  50% { opacity: 0.5; }
  100% { opacity: 0; transform: translateX(-50%) translateY(12px); }
}

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

/* =====================================================
   ABOUT SECTION
   ===================================================== */
.about {
  background: var(--color-bg);
}

.about__grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
  align-items: start;
}

@media (max-width: 900px) {
  .about__grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
}

.about__image-wrapper {
  position: relative;
}

.about__image {
  width: 100%;
  aspect-ratio: 3/4;
  object-fit: cover;
  border-radius: var(--radius-lg);
}


.about__content h3 {
  color: var(--color-text);
  margin-bottom: 1.5rem;
  font-size: 1.75rem;
}

.about__text {
  color: var(--color-text-secondary);
  line-height: 2;
  margin-bottom: 1.5rem;
}

.about__highlight {
  color: var(--color-primary-light);
  font-weight: 500;
}

/* =====================================================
   CAREER TIMELINE
   ===================================================== */
.career {
  background: var(--color-surface);
}

.timeline {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--color-primary), var(--color-primary-light), var(--color-surface-light));
}

@media (max-width: 768px) {
  .timeline::before {
    left: 15px;
  }
}

.timeline__item {
  position: relative;
  padding-left: 3rem;
  padding-bottom: 3rem;
  opacity: 0;
  transform: translateX(-20px);
  transition: all 0.6s ease;
}

.timeline__item.visible {
  opacity: 1;
  transform: translateX(0);
}

.timeline__item:last-child {
  padding-bottom: 0;
}

.awards .timeline__item {
  padding-bottom: 1.25rem;
}

.awards .timeline__item:last-child {
  padding-bottom: 0;
}

/* Timeline with Logo */
.timeline--with-logo {
  border-left: 2px solid var(--color-border);
}

.timeline__item--with-logo {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding-left: 3rem;
  padding-bottom: 2rem;
  position: relative;
}

.timeline__item--with-logo:last-child {
  padding-bottom: 0;
}

.timeline__logo {
  width: 40px;
  height: 40px;
  object-fit: contain;
  background: #ffffff;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
  padding: 4px;
}

.timeline__logo--large {
  width: 50px;
  height: 50px;
}

.timeline__content {
  flex: 1;
}

@media (max-width: 768px) {
  .timeline__item--with-logo {
    gap: 0.75rem;
    padding-left: 1.5rem;
  }

  .timeline__logo {
    width: 32px;
    height: 32px;
  }

  .timeline__logo--large {
    width: 40px;
    height: 40px;
  }
}

.timeline__marker {
  position: absolute;
  left: -6px;
  top: 0;
  width: 14px;
  height: 14px;
  background: var(--color-primary);
  border-radius: 50%;
  border: 3px solid var(--color-surface);
  box-shadow: 0 0 0 3px var(--color-primary);
}

@media (max-width: 768px) {
  .timeline__item {
    padding-left: 3.5rem;
  }

  .timeline__marker {
    left: 9px;
  }
}

.timeline__date {
  font-size: 0.875rem;
  color: var(--color-primary-light);
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.timeline__title {
  font-size: 1.25rem;
  color: var(--color-text);
  margin-bottom: 0.25rem;
}

.timeline__subtitle {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  font-style: italic;
  margin-bottom: 0.75rem;
}

.timeline__description {
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}


.timeline__description ul {
  list-style: none;
  padding-left: 0;
}

.timeline__description li {
  position: relative;
  padding-left: 1.25rem;
  margin-bottom: 0.5rem;
}

.timeline__description li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--color-primary-light);
}

/* Timeline Project Subsections */
.timeline__project {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.timeline__project:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.timeline__project-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 0.5rem;
}

.timeline__project-meta {
  font-size: 0.85rem;
  color: var(--color-primary-light);
  margin-bottom: 0.75rem;
  font-weight: 500;
}

.timeline__project-overview {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 1rem;
  padding-left: 0.75rem;
  border-left: 2px solid var(--color-primary-light);
}

.timeline__subsection-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-text);
  margin-top: 1rem;
  margin-bottom: 0.75rem;
}

.timeline__description .timeline__nested-list {
  margin-left: 0.5rem;
}

.timeline__description .timeline__nested-list > li {
  margin-bottom: 0.75rem;
}

.timeline__description .timeline__nested-list > li > strong {
  color: var(--color-text);
  font-weight: 600;
  display: block;
  margin-bottom: 0.25rem;
}

.timeline__description .timeline__sub-items {
  margin-top: 0.5rem;
  padding-left: 1rem;
}

.timeline__description .timeline__sub-items li {
  font-size: 0.875rem;
  margin-bottom: 0.35rem;
  color: var(--color-text-muted);
}

.timeline__description .timeline__sub-items li::before {
  content: '◦';
  font-size: 0.75rem;
}

/* Timeline Inline Link (Report/GitHub badge) */
.timeline__inline-link {
  display: inline-block;
  margin-left: 0.5rem;
  padding: 0.125rem 0.5rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary);
  background: rgba(37, 99, 235, 0.08);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: all var(--transition-fast);
  vertical-align: middle;
}

.timeline__inline-link:hover {
  background: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
}

/* Timeline Link Card */
.timeline__link-card {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem;
  margin-top: 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.timeline__link-card:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

.timeline__link-card-image {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.timeline__link-card-content {
  flex: 1;
  min-width: 0;
}

.timeline__link-card-title {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.timeline__link-card-title i {
  font-size: 0.7rem;
  color: var(--color-text-muted);
}

/* Timeline Categories */
.timeline__category {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  letter-spacing: 0.02em;
  margin-top: 1.25rem;
  margin-bottom: 0.4rem;
  padding-bottom: 0.3rem;
  border-bottom: 1px solid var(--color-surface-light);
}

.timeline__category:first-child {
  margin-top: 0;
}

/* =====================================================
   SKILLS SECTION
   ===================================================== */
.skills {
  background: var(--color-bg);
}

.skills__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.skills__category {
  background: var(--color-surface);
  padding: 2rem;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(0, 0, 0, 0.08);
  transition: all var(--transition-base);
}

.skills__category:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary);
  box-shadow: 0 10px 40px rgba(37, 99, 235, 0.15);
}

.skills__category-title {
  font-size: 1rem;
  color: var(--color-primary-light);
  margin-bottom: 1.25rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.skills__category-title i {
  font-size: 1.25rem;
}

.skills__subgroup-title {
  font-size: 0.9rem;
  color: var(--color-text);
  margin-top: 1.25rem;
  margin-bottom: 0.75rem;
  font-weight: 600;
  border-left: 3px solid var(--color-primary);
  padding-left: 0.75rem;
  line-height: 1.2;
}

.skills__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.skill-tag {
  display: inline-flex;
  align-items: center;
  padding: 0.375rem 0.75rem;
  background: rgba(37, 99, 235, 0.1);
  color: var(--color-text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(37, 99, 235, 0.2);
  transition: all var(--transition-fast);
}

.skill-tag:hover {
  background: rgba(37, 99, 235, 0.2);
  color: var(--color-text);
  border-color: var(--color-primary);
}

/* =====================================================
   PROJECTS SECTION
   ===================================================== */
.projects {
  background: var(--color-surface);
}

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

.projects--educational {
  background: var(--color-surface);
}

/* Project Filter Tabs */
.projects__filter {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

.projects__filter-btn {
  padding: 0.5rem 1rem;
  border: none;
  background: transparent;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: color var(--transition-base);
  position: relative;
}

.projects__filter-btn:not(:last-child)::after {
  content: '|';
  position: absolute;
  right: -2px;
  color: var(--color-border);
  font-weight: 300;
}

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

.projects__filter-btn--active {
  color: var(--color-primary);
  font-weight: 600;
}

.project-card--hidden {
  display: none !important;
}

.project-card--coming-soon {
  opacity: 0.7;
  cursor: default;
}

.project-card--coming-soon:hover {
  transform: none;
  box-shadow: none;
}

.project-card__coming-soon-overlay {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 200px;
  background: linear-gradient(135deg, var(--color-surface) 0%, var(--color-surface-light) 100%);
  color: var(--color-text-secondary);
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.05em;
}

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

@media (max-width: 400px) {
  .projects__grid {
    grid-template-columns: 1fr;
  }
}

.project-card {
  background: var(--color-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(0, 0, 0, 0.08);
  transition: all var(--transition-base);
  cursor: pointer;
  display: flex;
  flex-direction: column;
  max-width: 500px;
}

.project-card:hover {
  transform: translateY(-8px);
  border-color: var(--color-primary);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

/* Hidden project cards */
.project-card.hidden {
  display: none;
  opacity: 0;
  transform: translateY(20px);
}

.project-card.hidden.show {
  display: block;
  animation: fadeInCard 0.5s ease forwards;
}

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

.project-card__image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.project-card:hover .project-card__image {
  transform: scale(1.05);
}

.project-card__image-wrapper {
  overflow: hidden;
  position: relative;
}

.project-card__status {
  position: absolute;
  top: 1rem;
  right: 1rem;
  padding: 0.25rem 0.75rem;
  background: var(--color-primary);
  color: var(--color-text);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
  z-index: 2;
}

.project-card__status--wip {
  background: var(--color-warning);
  color: var(--color-bg);
}

/* Category Badge */
.project-card__category {
  position: absolute;
  top: 1rem;
  left: 1rem;
  padding: 0.25rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
  z-index: 2;
}

.project-card__category--professional {
  background: linear-gradient(135deg, #2563eb, #3b82f6);
  color: #ffffff;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.4);
}

.project-card__category--educational {
  background: linear-gradient(135deg, #10b981, #34d399);
  color: #ffffff;
  box-shadow: 0 2px 8px rgba(16, 185, 129, 0.4);
}

.project-card__content {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.project-card__title {
  font-size: 1.125rem;
  color: var(--color-text);
  margin-bottom: 0.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.project-card__category-text {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.project-card__title-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 1.125rem;
}

.project-card__link {
  color: var(--color-text-muted);
  font-size: 1.25rem;
  transition: color var(--transition-fast);
}

.project-card__link:hover {
  color: var(--color-primary-light);
}

.project-card__description {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 1rem;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.project-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: auto;
}

.project-card__tag {
  padding: 0.25rem 0.5rem;
  background: rgba(37, 99, 235, 0.1);
  color: var(--color-primary-light);
  font-size: 0.75rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
}

/* Project Card Footer - GitHub Button */
.project-card__footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.03);
}

.project-card__github-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 500;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.project-card__github-btn:hover {
  background: var(--color-text);
  color: var(--color-bg);
  border-color: var(--color-text);
}

.project-card__github-btn i {
  font-size: 1rem;
}

.project-card__footer-note {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.project-card__footer-note i {
  font-size: 0.9rem;
}

/* Show More Button */
.projects__show-more {
  display: flex;
  justify-content: center;
  margin-top: 3rem;
}

.show-more-btn {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  background: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-base);
}

.show-more-btn:hover {
  background: var(--color-primary);
  color: #ffffff;
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.3);
}

.show-more-btn__icon {
  font-size: 0.875rem;
  transition: transform var(--transition-base);
}

.show-more-btn.expanded .show-more-btn__icon {
  transform: rotate(180deg);
}

/* Project Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 2000;
  overflow-y: auto;
  padding: 2rem;
}

.modal.active {
  display: flex;
  align-items: flex-start;
  justify-content: center;
}

.modal__content {
  background: var(--color-surface);
  border-radius: var(--radius-xl);
  max-width: 900px;
  width: 100%;
  margin: 2rem auto;
  position: relative;
  animation: modalIn 0.3s ease;
}

@keyframes modalIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.modal__close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 40px;
  height: 40px;
  background: var(--color-bg);
  border: none;
  border-radius: 50%;
  color: var(--color-text);
  font-size: 1.5rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  z-index: 10;
}

.modal__close:hover {
  background: var(--color-primary);
}

.modal__image {
  width: 100%;
  height: 300px;
  object-fit: cover;
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.modal__image--contain {
  object-fit: contain;
  background-color: var(--color-surface);
}

.modal__body {
  padding: 2rem;
}

.modal__title {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--color-text);
}

.modal__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.modal__meta-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.modal__meta-item i {
  color: var(--color-primary-light);
}

.modal__section {
  margin-bottom: 1.5rem;
}

/* Highlight Section (CTA - Try Demo 등) */
.modal__section--highlight {
  background: rgba(37, 99, 235, 0.08);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  border-left: 4px solid var(--color-primary);
  margin-bottom: 1.5rem;
}

.modal__section--highlight .modal__section-title {
  color: var(--color-primary);
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
}

.modal__section--highlight p {
  color: var(--color-text);
  margin: 0;
}

.modal__section--highlight a {
  color: var(--color-primary);
  font-weight: 600;
}

.modal__section--highlight a:hover {
  color: var(--color-primary-light);
  text-decoration: underline;
}

.modal__section-title {
  font-size: 1rem;
  color: var(--color-primary-light);
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.modal__section p,
.modal__section li {
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.modal__section ul {
  list-style: none;
  padding-left: 0;
}

.modal__section li {
  position: relative;
  padding-left: 1.25rem;
  margin-bottom: 0.5rem;
}

.modal__section li::before {
  content: '·';
  position: absolute;
  left: 0;
  color: var(--color-primary-light);
  font-weight: 700;
  font-size: 1.2em;
}

.modal__rich-content {
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 0.5rem;
}

.modal__section table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.85rem;
}

.modal__section th,
.modal__section td {
  padding: 0.5rem 0.75rem;
  text-align: left;
  border-bottom: 1px solid #e2e8f0;
}

.modal__section th {
  background: var(--color-surface);
  font-weight: 600;
  color: var(--color-text);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.modal__section td {
  color: var(--color-text-secondary);
}

.modal__section tr:hover td {
  background: #f8fafc;
}

.modal__section td strong {
  color: var(--color-primary);
}

.modal__demo-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  color: #ffffff;
  font-weight: 600;
  border-radius: var(--radius-md);
  margin-top: 1.5rem;
  margin-bottom: 1rem;
  transition: all var(--transition-base);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.modal__demo-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.4);
  color: #ffffff;
}

.modal__demo-btn i {
  font-size: 1rem;
}

.modal__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(0, 0, 0, 0.1);
}

/* =====================================================
   MODAL DISCLAIMER (회사 프로젝트용)
   ===================================================== */
.modal__disclaimer {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  margin-bottom: 1.5rem;
  background: rgba(245, 158, 11, 0.1);
  border: 1px solid rgba(245, 158, 11, 0.3);
  border-radius: var(--radius-md);
  border-left: 4px solid #f59e0b;
}

.modal__disclaimer i {
  color: #f59e0b;
  font-size: 1.25rem;
  flex-shrink: 0;
  margin-top: 0.125rem;
}

.modal__disclaimer p {
  color: var(--color-text-secondary);
  font-size: 0.85rem;
  line-height: 1.6;
  margin: 0;
}

/* Subsection 스타일 */
.modal__subsection {
  margin-top: 1rem;
  padding-left: 1rem;
  border-left: 2px solid var(--color-border);
}

.modal__subsection-title {
  font-size: 0.95rem;
  color: var(--color-text);
  font-weight: 600;
  margin-bottom: 0.5rem;
}

/* Section Image 스타일 */
.modal__section-image {
  width: 100%;
  max-width: 100%;
  border-radius: var(--radius-md);
  margin: 1rem 0;
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.modal__section-image:hover {
  transform: scale(1.02);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.modal__section-image-caption {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  text-align: center;
  margin-top: 0.5rem;
  font-style: italic;
}

/* Subsection Image 스타일 */
.modal__subsection-image {
  width: 100%;
  max-width: 100%;
  border-radius: var(--radius-md);
  margin: 0.75rem 0;
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.modal__subsection-image:hover {
  transform: scale(1.01);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
}

/* Image Gallery 스타일 (여러 이미지) */
.modal__image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
  margin: 1rem 0;
}

.modal__gallery-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.modal__gallery-item img {
  width: 100%;
  height: 200px;
  object-fit: contain;
  background-color: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.modal__gallery-item img:hover {
  transform: scale(1.02);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.modal__gallery-item span {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  margin-top: 0.5rem;
  text-align: center;
}

/* Video 지원 */
.modal__video-wrapper {
  margin: 1rem 0;
}

.modal__video {
  width: 100%;
  max-height: 500px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: #000;
}

.modal__video-caption {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  text-align: center;
  margin-top: 0.5rem;
}

/* Subsection Gallery (2열 병렬 배치) */
.modal__subsection-gallery {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin: 1rem 0;
}

.modal__subsection-gallery-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.modal__subsection-gallery-item img {
  width: 100%;
  height: 280px;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.modal__subsection-gallery-item img:hover {
  transform: scale(1.02);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.modal__subsection-gallery-item span {
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  margin-top: 0.5rem;
  text-align: center;
}

@media (max-width: 600px) {
  .modal__subsection-gallery {
    grid-template-columns: 1fr;
  }
}

/* =====================================================
   CONTACT SECTION
   ===================================================== */
.contact {
  background: var(--color-bg);
  text-align: center;
}

.contact__content {
  max-width: 600px;
  margin: 0 auto;
}

.contact__title {
  font-size: clamp(2rem, 4vw, 3rem);
  margin-bottom: 1rem;
}

.contact__description {
  color: var(--color-text-secondary);
  margin-bottom: 3rem;
  font-size: 1.125rem;
}

.contact__links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.contact__link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  background: var(--color-surface);
  color: var(--color-text);
  border-radius: var(--radius-lg);
  font-weight: 500;
  transition: all var(--transition-base);
  border: 1px solid transparent;
}

.contact__link i {
  font-size: 1.25rem;
  color: var(--color-primary-light);
}

.contact__link:hover {
  background: var(--color-primary);
  transform: translateY(-4px);
  box-shadow: 0 10px 30px rgba(37, 99, 235, 0.3);
}

.contact__link:hover i {
  color: var(--color-text);
}

/* Social Links in Contact */
.contact__social {
  display: flex;
  justify-content: center;
  gap: 3rem;
  margin-top: 3rem;
}

.contact__social-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

.contact__social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 1.5rem;
  border-radius: 50%;
  transition: all var(--transition-base);
  border: 1px solid transparent;
}

.contact__social-link:hover {
  background: var(--color-primary);
  border-color: var(--color-primary-light);
  transform: translateY(-4px);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.3);
  color: #ffffff;
}

.contact__social-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  text-align: center;
}

/* Popover */
.contact__popover-wrapper {
  position: relative;
}

.contact__popover {
  position: absolute;
  bottom: calc(100% + 12px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
  white-space: nowrap;
  z-index: 100;
}

.contact__popover::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 8px solid transparent;
  border-top-color: var(--color-border);
}

.contact__popover::before {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 7px solid transparent;
  border-top-color: var(--color-surface);
  z-index: 1;
}

.contact__popover.show {
  opacity: 1;
  visibility: visible;
}

.contact__popover-text {
  font-size: 0.9rem;
  color: var(--color-text);
  font-weight: 500;
}

.contact__popover-copy {
  background: transparent;
  border: none;
  color: var(--color-text-secondary);
  cursor: pointer;
  padding: 0.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color var(--transition-fast);
}

.contact__popover-copy:hover {
  color: var(--color-primary);
}

.contact__popover-copy.copied {
  color: #22c55e;
}

/* Profile Popover */
.contact__popover--profile {
  min-width: 320px;
  padding: 1.25rem;
}

.profile__info {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.profile__info-item {
  display: grid;
  grid-template-columns: 24px 1fr auto;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.9rem;
  color: var(--color-text);
}

.profile__info-item i {
  font-size: 1rem;
  color: var(--color-primary-light);
  width: 24px;
  text-align: left;
}

.profile__info-item span {
  font-weight: 500;
  text-align: left;
}

.profile__info-item .contact__popover-copy {
  justify-self: end;
}

/* =====================================================
   FOOTER
   ===================================================== */
.footer {
  background: var(--color-surface);
  padding: 2rem 0;
  text-align: center;
  border-top: 1px solid rgba(0, 0, 0, 0.08);
}

.footer__text {
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

.footer__text a {
  color: var(--color-primary-light);
}

/* =====================================================
   UTILITIES
   ===================================================== */
.text-gradient {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s ease;
}

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

.fade-in-left {
  opacity: 0;
  transform: translateX(-30px);
  transition: all 0.8s ease;
}

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

.fade-in-right {
  opacity: 0;
  transform: translateX(30px);
  transition: all 0.8s ease;
}

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

/* Stagger animation delay */
.stagger-1 { transition-delay: 0.1s; }
.stagger-2 { transition-delay: 0.2s; }
.stagger-3 { transition-delay: 0.3s; }
.stagger-4 { transition-delay: 0.4s; }
.stagger-5 { transition-delay: 0.5s; }
.stagger-6 { transition-delay: 0.6s; }

/* Hide scrollbar but keep functionality */
.no-scrollbar {
  -ms-overflow-style: none;
  scrollbar-width: none;
}

.no-scrollbar::-webkit-scrollbar {
  display: none;
}

/* Body scroll lock when modal is open */
body.modal-open {
  overflow: hidden;
}

/* Reduced motion for accessibility */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}