/* ============================================
   YUMO — Portfolio Styles
   Design: Minimal, dark, developer-focused
   Inspired by: linear.app, vercel.com
   ============================================ */

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

:root {
  --bg: #0a0a0a;
  --bg-elevated: #111111;
  --bg-card: #141414;
  --bg-card-hover: #1a1a1a;
  --border: #1e1e1e;
  --border-hover: #2a2a2a;
  --text: #ededed;
  --text-secondary: #888888;
  --text-tertiary: #555555;
  --accent: #3b82f6;
  --accent-hover: #60a5fa;
  --accent-glow: rgba(59, 130, 246, 0.15);
  --gradient-1: #3b82f6;
  --gradient-2: #8b5cf6;
  --green: #22c55e;
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono: 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 1100px;
  --transition: 0.2s ease;
}

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

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

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

/* --- Utilities --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.gradient-text {
  background: linear-gradient(135deg, var(--gradient-1), var(--gradient-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.accent {
  color: var(--accent);
}

/* --- Page Load Animation --- */
body:not(.loaded) .hero-content {
  opacity: 0;
  transform: translateY(30px);
}

body.loaded .hero-content {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

/* --- Nav --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(10, 10, 10, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: -0.02em;
  transition: text-shadow 0.3s ease;
}

.nav-logo:hover {
  text-shadow: 0 0 12px var(--accent-glow), 0 0 24px rgba(59, 130, 246, 0.1);
}

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

.nav-links a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: color var(--transition);
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--text);
}

/* Mobile menu button */
.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.mobile-menu-btn span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: all 0.3s ease;
}

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

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

.mobile-menu-btn.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

.mobile-menu {
  display: none;
  flex-direction: column;
  padding: 16px 24px 24px;
  gap: 16px;
  border-top: 1px solid var(--border);
}

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

.mobile-menu a {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition);
}

.mobile-menu a:hover {
  color: var(--text);
}

/* --- Hero --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding: 120px 0 80px;
}

#hero-particles {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 32px;
}

.status-dot {
  width: 8px;
  height: 8px;
  background: var(--green);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 24px;
}

/* Typewriter cursor */
.typewriter {
  border-right: 2px solid var(--accent);
  padding-right: 2px;
  animation: blink-cursor 0.8s step-end infinite;
}

.typewriter.typing-done {
  animation: blink-cursor 1s step-end infinite;
}

@keyframes blink-cursor {
  50% { border-color: transparent; }
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.7;
  margin-bottom: 40px;
}

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

.hero-gradient {
  position: absolute;
  top: 0;
  right: -20%;
  width: 60%;
  height: 60%;
  background: radial-gradient(ellipse at center, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius);
  font-size: 0.9375rem;
  font-weight: 500;
  font-family: var(--font);
  cursor: pointer;
  transition: all var(--transition);
  border: none;
  text-decoration: none;
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.3);
}

.btn-secondary {
  background: var(--bg-elevated);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  color: var(--text);
  border-color: var(--border-hover);
  transform: translateY(-1px);
}

/* --- Sections --- */
.section {
  padding: 120px 0;
}

.section-alt {
  background: var(--bg-elevated);
}

.section-label {
  font-family: var(--mono);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 48px;
}

/* --- About --- */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}

.about-content h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
  line-height: 1.2;
}

.about-content p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.75;
  font-size: 0.9375rem;
}

.about-content p:last-child {
  margin-bottom: 0;
}

.about-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.stat-card:hover {
  border-color: var(--border-hover);
  box-shadow: 0 4px 24px rgba(59, 130, 246, 0.08);
  transform: translateY(-2px);
}

.stat-number {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 2px;
}

.stat-desc {
  font-size: 0.75rem;
  color: var(--text-tertiary);
}

/* --- Timeline / Journey --- */
.timeline {
  position: relative;
  padding-left: 40px;
}

.timeline-line {
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), var(--gradient-2));
  opacity: 0.3;
}

.timeline-entries {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.timeline-entry {
  position: relative;
}

.timeline-dot {
  position: absolute;
  left: -33px;
  top: 24px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--text-tertiary);
  z-index: 1;
  transition: all 0.3s ease;
}

.timeline-dot.active {
  border-color: var(--accent);
  background: var(--accent);
  box-shadow: 0 0 12px rgba(59, 130, 246, 0.4);
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.timeline-card:hover {
  border-color: var(--border-hover);
  box-shadow: 0 4px 24px rgba(59, 130, 246, 0.06);
  transform: translateX(4px);
}

.timeline-card.active {
  border-color: rgba(59, 130, 246, 0.3);
  background: linear-gradient(135deg, var(--bg-card) 0%, rgba(59, 130, 246, 0.03) 100%);
}

.timeline-step {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent);
  margin-bottom: 8px;
  letter-spacing: 0.05em;
}

.timeline-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.timeline-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* --- Projects --- */
.project-featured {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 48px;
  margin-bottom: 32px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.project-featured:hover {
  border-color: var(--border-hover);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.08);
}

.project-featured-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  flex-wrap: wrap;
  gap: 16px;
}

.project-icon {
  width: 48px;
  height: 48px;
  background: var(--accent-glow);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}

.project-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  padding: 4px 12px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.15);
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--accent);
  font-family: var(--mono);
}

.project-featured-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.project-featured-desc {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.75;
  margin-bottom: 32px;
  max-width: 700px;
}

.project-features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 12px;
  margin-bottom: 32px;
}

.feature {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.feature svg {
  color: var(--green);
  flex-shrink: 0;
}

.project-actions {
  display: flex;
  gap: 12px;
}

/* Project cards grid */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 16px;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: all var(--transition);
}

.project-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.1);
}

.project-card-icon {
  width: 40px;
  height: 40px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

.project-card h4 {
  font-size: 1.0625rem;
  font-weight: 600;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.project-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 16px;
}

.project-card-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.tag-sm {
  padding: 3px 10px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 0.6875rem;
  color: var(--text-tertiary);
  font-family: var(--mono);
  font-weight: 500;
}

/* --- Skills --- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.skill-group {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.skill-group:hover {
  border-color: var(--border-hover);
  box-shadow: 0 4px 24px rgba(59, 130, 246, 0.06);
  transform: translateY(-2px);
}

.skill-group h4 {
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.skill-items {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.skill-item {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text);
  padding-left: 12px;
  border-left: 2px solid var(--border);
  transition: border-color var(--transition), padding-left var(--transition);
}

.skill-item:hover {
  border-left-color: var(--accent);
  padding-left: 16px;
}

/* --- Contact --- */
.contact-block {
  max-width: 600px;
}

.contact-block h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.contact-block p {
  color: var(--text-secondary);
  font-size: 1.0625rem;
  line-height: 1.7;
  margin-bottom: 32px;
}

.contact-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
}

.contact-link:hover {
  color: var(--text);
  border-color: var(--border-hover);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.08);
}

/* --- Footer --- */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
}

.footer p {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
  text-align: center;
}

/* --- Scroll Animations --- */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* --- Selection --- */
::selection {
  background: var(--accent);
  color: white;
}

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

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

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

::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}

/* ============================================
   Responsive
   ============================================ */

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

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

  .hero {
    padding: 100px 0 60px;
  }

  .hero-title {
    font-size: 2.25rem;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about-stats {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .project-featured {
    padding: 28px;
  }

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

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

  .skills-grid {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .skill-group {
    padding: 24px;
  }

  .section {
    padding: 80px 0;
  }

  .contact-links {
    flex-direction: column;
  }

  .contact-link {
    justify-content: center;
  }

  /* Timeline mobile */
  .timeline {
    padding-left: 32px;
  }

  .timeline-line {
    left: 11px;
  }

  .timeline-dot {
    left: -27px;
    width: 10px;
    height: 10px;
  }

  .timeline-card {
    padding: 20px 24px;
  }
}

@media (max-width: 480px) {
  .about-stats {
    grid-template-columns: 1fr;
  }

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

  .hero-actions {
    flex-direction: column;
  }

  .btn {
    justify-content: center;
    width: 100%;
  }

  .stat-card {
    padding: 20px;
  }
}