/* ============================================================================
   DESIGN TOKENS - COLOR PALETTE & TYPOGRAPHY
   ============================================================================ */
:root {
  color-scheme: light dark;
  
  /* Colors */
  --color-accent: light-dark(#0066cc, #4a9eff);
  --hover-color: light-dark(#0052a3, #3a8ee8);
  --background-color: light-dark(#cce5ff, rgba(74, 158, 255, 0.1));
  --primary-color: light-dark(#1a1a1a, #e0e0e0);
  --secondary-color: light-dark(#666, #aaa);
  --surface-color: light-dark(#f2f2f2, #2a2a2a);
  --border-color: light-dark(#e0e0e0, #444);
  --surface-color: light-dark(#f2f2f2, #2a2a2a);
  --code-color: light-dark(#d73a49, #f97583);
  
  /* Gradient */
  --gradient-banner: linear-gradient(135deg, light-dark(#0066cc, #1a4d99), light-dark(#4a9eff, #0066cc));
  
  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  --font-family-mono: 'Courier New', monospace;
  --font-size-xs: 12px;
  --font-size-sm: 13px;
  --font-size-base: 15px;
  --font-size-lg: 16px;
  --font-size-xl: 18px;
  --font-size-2xl: 20px;
  --font-size-3xl: 24px;
  --font-size-4xl: 28px;
  --font-size-5xl: 32px;
  --font-size-6xl: 36px;
  --font-size-7xl: 48px;
  
  /* Spacing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 12px;
  --spacing-lg: 16px;
  --spacing-xl: 24px;
  --spacing-2xl: 32px;
  --spacing-3xl: 48px;
  --spacing-4xl: 60px;
  
  /* Layout */
  --container-width: 1000px;
  --container-padding: var(--spacing-xl);
  --border-radius-sm: 4px;
  --border-radius-md: 6px;
  --border-radius-lg: 8px;
  --border-radius-xl: 12px;
  --border-radius-full: 50%;
  
  /* Transitions */
  --transition-fast: 0.2s;
  --transition-base: 0.3s;
  --transition-slow: 0.4s;
  
  /* Shadow */
  --shadow-sm: light-dark(0 2px 8px rgba(0,0,0,0.08), 0 2px 8px rgba(0,0,0,0.2));
  --shadow-md: light-dark(0 2px 12px rgba(0,0,0,0.08), 0 2px 12px rgba(0,0,0,0.3));
}


/* ============================================================================
   GLOBAL STYLES
   ============================================================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  line-height: 1.6;
  color: var(--primary-color);
  background: var(--surface-color);
  transition: background var(--transition-base), color var(--transition-base);
}

/* ============================================================================
   NAVBAR
   ============================================================================ */

.navbar {
  position: static;
  background: var(--surface-color);
  border-block-end: 1px solid var(--border-color);
  z-index: 1000;
  box-shadow: var(--shadow-md);
}

.nav-container {
  max-width: var(--container-width);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-inline: var(--container-padding);
  block-size: 60px;
}

.logo {
  font-weight: 700;
  font-size: var(--font-size-lg);
  color: var(--color-accent);
  text-decoration: none;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: var(--spacing-2xl);
}

.nav-links a {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

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

.theme-toggle {
  background: var(--surface-color);
  border: 1px solid var(--border-color);
  color: var(--primary-color);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius-md);
  cursor: pointer;
  font-weight: 600;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  background: var(--color-accent);
  color: white;
  border-color: var(--color-accent);
}

/* ============================================================================
   MAIN CONTENT
   ============================================================================ */

main {
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: var(--container-padding);
}

.section {
  padding-block: var(--spacing-4xl);
  border-block-end: 1px solid var(--border-color);
}

.section:last-of-type {
  border-block-end: none;
}

.section-title {
  font-size: var(--font-size-5xl);
  font-weight: 700;
  margin-block-end: var(--spacing-2xl);
  color: var(--primary-color);
}

/* ============================================================================
   PROFILE HEADER (TWITTER-LIKE)
   ============================================================================ */

.profile-header {
  background: var(--surface-color);
  border-block-end: 1px solid var(--border-color);
  margin-block-end: var(--spacing-3xl);
  inline-size: 100vw;
  position: relative;
  inset-inline-start: 50%;
  inset-inline-end: 50%;
  margin-inline-start: -50vw;
  margin-inline-end: -50vw;
}

.profile-banner {
  inline-size: 100%;
  block-size: 200px;
  background: var(--gradient-banner);
  position: relative;
}

.banner-links {
  display: flex;
  gap: var(--spacing-md);
  position: absolute;
  inset-block-end: var(--spacing-lg);
  inset-inline-end: var(--container-padding);
  flex-wrap: wrap;
  justify-content: flex-end;
}

.banner-link-item {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--surface-color);
  color: var(--accent-color);
  text-decoration: none;
  border-radius: 18px;
  font-size: var(--font-size-sm);
  font-weight: 600;
  transition: background var(--transition-fast), transform var(--transition-fast);
  box-shadow: var(--shadow-sm);
  white-space: nowrap;
}

.banner-link-item:hover {
  background: #fff;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.profile-info-container {
  display: flex;
  gap: var(--spacing-xl);
  padding-inline: var(--container-padding);
  position: relative;
  max-width: var(--container-width);
  margin-inline: auto;
  align-items: flex-end;
}

.profile-photo {
  flex-shrink: 0;
  margin-block-start: -110px;
  margin-block-end: 0;
  inline-size: 220px;
  block-size: 220px;
  border-radius: var(--border-radius-full);
  border: 4px solid var(--surface-color);
  object-fit: cover;
  display: block;
}

.profile-details {
  padding-block: var(--spacing-lg);
  flex: 1;
  min-inline-size: 0;
}

.profile-name {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  color: var(--primary-color);
  margin-block-end: var(--spacing-xs);
}

.profile-title {
  font-size: var(--font-size-lg);
  color: var(--color-accent);
  font-weight: 600;
  margin-block-end: var(--spacing-sm);
}

.profile-tagline {
  font-size: var(--font-size-base);
  color: var(--secondary-color);
  margin-block: 0 var(--spacing-md);
  max-inline-size: 600px;
  line-height: 1.5;
}

/* ============================================================================
   PROFILE TABS
   ============================================================================ */

.profile-tabs {
  display: flex;
  border-block-start: 1px solid var(--border-color);
  inline-size: 100vw;
  position: sticky;
  inset-block-start: 0;
  z-index: 999;
  background: var(--surface-color);
  inset-inline-start: 50%;
  inset-inline-end: 50%;
  margin-inline-start: -50vw;
  margin-inline-end: -50vw;
}

.tab-list {
  display: flex;
  list-style: none;
  gap: 0;
  margin: 0;
  padding-inline: var(--container-padding);
  inline-size: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
}

.tab-list li {
  flex: 0 0 auto;
}

.tab-link {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-inline: var(--spacing-xl);
  padding-block: var(--spacing-lg);
  color: var(--secondary-color);
  text-decoration: none;
  font-weight: 600;
  font-size: var(--font-size-base);
  border-block-end: 3px solid transparent;
  transition: color var(--transition-fast), border-block-end var(--transition-fast);
  cursor: pointer;
  white-space: nowrap;
}

.tab-link:hover {
  color: var(--color-accent);
  background: var(--background-color);
}

.tab-link.active {
  color: var(--color-accent);
  border-block-end-color: var(--color-accent);
}

/* ============================================================================
   ABOUT SECTION
   ============================================================================ */

.about-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-3xl);
}

.about-text h3 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-block-end: var(--spacing-lg);
}

.about-text p {
  color: var(--secondary-color);
  margin-block-end: var(--spacing-lg);
}

.cv-link {
  display: inline-block;
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
  border: 2px solid var(--color-accent);
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
}

.cv-link:hover {
  background: var(--color-accent);
  color: white;
}

/* ============================================================================
   EDUCATION SECTION
   ============================================================================ */

.education-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.education-card {
  background: var(--surface-color);
  padding: var(--spacing-xl);
  border-radius: var(--border-radius-lg);
  border-inline-start: 4px solid var(--color-accent);
}

.education-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-block-end: var(--spacing-sm);
}

.education-card .institution {
  color: var(--color-accent);
  font-weight: 600;
  margin-block-end: var(--spacing-sm);
}

.education-card .dates {
  color: var(--secondary-color);
  font-size: var(--font-size-sm);
  margin-block-end: var(--spacing-md);
}

.education-card .notes {
  color: var(--secondary-color);
  font-size: var(--font-size-sm);
  font-style: italic;
}

/* ============================================================================
   PROJECTS SECTION
   ============================================================================ */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
}

.project-card {
  background: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  transition: box-shadow var(--transition-fast);
}

.project-card:hover {
  box-shadow: var(--shadow-md);
}

.project-image {
  inline-size: 100%;
  block-size: 200px;
  background: var(--surface-color-light);
  overflow: hidden;
}

.project-image img {
  inline-size: 100%;
  block-size: 100%;
  object-fit: cover;
}

.project-content {
  padding: var(--spacing-xl);
}

.project-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-block-end: var(--spacing-sm);
}

.project-content p {
  color: var(--secondary-color);
  margin-block-end: var(--spacing-lg);
  font-size: var(--font-size-sm);
}

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-block-end: var(--spacing-lg);
}

.tech-tag {
  background: var(--color-accent);
  color: white;
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: 20px;
  font-size: var(--font-size-xs);
  font-weight: 600;
}

.project-detail-tech .tech-tag {
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius-sm);
  font-weight: 500;
}

.project-links {
  display: flex;
  gap: var(--spacing-md);
}

.project-links a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
  font-size: var(--font-size-sm);
  transition: color var(--transition-fast);
}

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

/* ============================================================================
   SKILLS SECTION
   ============================================================================ */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

.skill-category {
  background: var(--surface-color);
  padding: var(--spacing-xl);
  border-radius: var(--border-radius-lg);
}

.skill-category h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-block-end: var(--spacing-lg);
  color: var(--color-accent);
}

.skill-category ul {
  list-style: none;
}

.skill-category li {
  padding-block: var(--spacing-sm);
  color: var(--secondary-color);
}

.skill-category li::before {
  content: '✓ ';
  color: var(--color-accent);
  font-weight: 700;
  margin-inline-end: var(--spacing-sm);
}

/* ============================================================================
   CONTACT SECTION
   ============================================================================ */

.contact-container {
  text-align: center;
  max-inline-size: 600px;
  margin-inline: auto;
}

.contact-container p {
  font-size: var(--font-size-lg);
  color: var(--secondary-color);
  margin-block-end: var(--spacing-2xl);
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--spacing-xl);
  margin-block-end: var(--spacing-2xl);
}

.contact-links a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--transition-fast);
}

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

/* ============================================================================
   FOOTER
   ============================================================================ */

.footer {
  background: var(--surface-color);
  padding-block: var(--spacing-2xl);
  padding-inline: var(--container-padding);
  text-align: center;
  color: var(--secondary-color);
  border-block-start: 1px solid var(--border-color);
  margin-block-start: var(--spacing-2xl);
}

/* ============================================================================
   LOADING & ERROR STATES
   ============================================================================ */

.loading-state {
  display: flex;
  align-items: center;
  justify-content: center;
  min-block-size: 60vh;
  flex-direction: column;
}

.spinner {
  border: 4px solid var(--surface-color);
  border-block-start-color: var(--color-accent);
  border-radius: var(--border-radius-full);
  inline-size: 40px;
  block-size: 40px;
  animation: spin 0.8s linear infinite;
  margin-block-end: var(--spacing-lg);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-text {
  color: var(--secondary-color);
  font-size: var(--font-size-lg);
}

.error-state {
  display: flex;
  align-items: center;
  justify-content: center;
  min-block-size: 60vh;
  flex-direction: column;
  text-align: center;
}

.error-icon {
  font-size: var(--font-size-7xl);
  margin-block-end: var(--spacing-lg);
}

.error-state h2 {
  color: var(--primary-color);
  margin-block-end: var(--spacing-sm);
}

.error-state p {
  color: var(--secondary-color);
  margin-block-end: var(--spacing-xl);
}

.retry-btn {
  background: var(--color-accent);
  color: white;
  border: none;
  padding: var(--spacing-md) var(--spacing-2xl);
  border-radius: var(--border-radius-md);
  cursor: pointer;
  font-weight: 600;
  transition: opacity var(--transition-fast);
}

.retry-btn:hover {
  opacity: 0.8;
}

/* ============================================================================
   PROJECT DETAIL PAGE
   ============================================================================ */

.project-detail-back {
  display: inline-block;
  margin-block-start: var(--spacing-2xl);
  margin-block-end: var(--spacing-lg);
  color: var(--color-accent);
  text-decoration: none;
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.project-detail-back:hover {
  text-decoration: underline;
}

.project-detail-title {
  font-size: var(--font-size-6xl);
  font-weight: 700;
  margin-block-end: var(--spacing-lg);
  color: var(--primary-color);
}

.project-detail-container {
  display: flex;
  gap: var(--spacing-2xl);
  align-items: flex-start;
  margin-block: var(--spacing-2xl);
}

.project-detail-left {
  flex: 0 0 45%;
  min-inline-size: 0;
}

.project-detail-right {
  flex: 1;
  min-inline-size: 0;
}

.project-detail-section {
  margin-block-end: var(--spacing-lg);
}

.project-detail-section h2 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-block-end: var(--spacing-lg);
  color: var(--primary-color);
}

.project-detail-section p {
  color: var(--secondary-color);
  line-height: 1.8;
}

.project-detail-tech {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.project-detail-readme {
  margin-block-start: var(--spacing-3xl);
  padding-block-start: var(--spacing-2xl);
  border-block-start: 1px solid var(--border-color);
}

.project-detail-readme h2 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-block-end: var(--spacing-lg);
  color: var(--primary-color);
}

.project-detail-readme-content {
  color: var(--secondary-color);
  line-height: 1.8;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

.project-detail-readme-content h2 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-block-start: var(--spacing-2xl);
  margin-block-end: var(--spacing-lg);
  color: var(--primary-color);
}

.project-detail-readme-content h3 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-block-start: var(--spacing-xl);
  margin-block-end: var(--spacing-md);
  color: var(--primary-color);
}

.project-detail-readme-content h4 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-block-start: var(--spacing-lg);
  margin-block-end: var(--spacing-sm);
  color: var(--primary-color);
}

.project-detail-readme-content p {
  margin-block-end: var(--spacing-lg);
}

.project-detail-readme-content strong {
  font-weight: 700;
  color: var(--primary-color);
}

.project-detail-readme-content em {
  font-style: italic;
}

.project-detail-readme-content code {
  background: var(--surface-color);
  color: var(--code-color);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  font-family: var(--font-family-mono);
  font-size: var(--font-size-sm);
}

.project-detail-readme-content pre {
  background: var(--surface-color);
  border-inline-start: 4px solid var(--color-accent);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  margin-block: var(--spacing-lg);
  overflow-x: auto;
}

.project-detail-readme-content pre code {
  background: none;
  color: var(--primary-color);
  padding: 0;
  font-size: var(--font-size-sm);
}

.project-detail-readme-content ul {
  list-style-position: inside;
  margin-block-end: var(--spacing-lg);
  margin-inline-start: var(--spacing-lg);
}

.project-detail-readme-content li {
  margin-block-end: var(--spacing-sm);
  line-height: 1.8;
}

.project-detail-readme-content a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
}

.project-detail-readme-content a:hover {
  text-decoration: underline;
}

/* ============================================================================
   SLIDESHOW
   ============================================================================ */

.slideshow-container {
  margin-block-start: var(--spacing-2xl);
}

.slideshow-wrapper {
  position: relative;
  background-color: var(--surface-color);
  border-radius: var(--border-radius-xl);
  overflow: hidden;
  aspect-ratio: 16 / 9;
  display: flex;
  align-items: center;
  justify-content: center;
}

.slideshow-img {
  inline-size: 100%;
  block-size: 100%;
  object-fit: contain;
  transition: transform var(--transition-slow), opacity var(--transition-slow);
}

.slideshow-counter {
  position: absolute;
  inset-block-end: var(--spacing-lg);
  inset-inline-end: var(--spacing-lg);
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius-md);
  font-size: var(--font-size-sm);
  font-weight: 600;
  z-index: 10;
}

.slideshow-buttons {
  position: absolute;
  inset-block-start: 50%;
  transform: translateY(-50%);
  inline-size: 100%;
  display: flex;
  justify-content: space-between;
  padding-inline: var(--spacing-lg);
  pointer-events: none;
  z-index: 9;
}

.slideshow-btn {
  background: rgba(0, 0, 0, 0.5);
  color: #fff;
  border: none;
  inline-size: 40px;
  block-size: 40px;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  font-size: var(--font-size-lg);
  font-weight: 600;
  pointer-events: auto;
  transition: background var(--transition-fast);
}

.slideshow-btn:hover {
  background: rgba(0, 0, 0, 0.7);
}

/* ============================================================================
   SLIDESHOW ANIMATIONS
   ============================================================================ */

@keyframes slideInFromRight {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes slideInFromLeft {
  from {
    transform: translateX(-100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes slideOutToLeft {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(-100%);
    opacity: 0;
  }
}

@keyframes slideOutToRight {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(100%);
    opacity: 0;
  }
}

.slideshow-img.slide-out-left {
  animation: slideOutToLeft var(--transition-slow) ease-in-out forwards;
}

.slideshow-img.slide-out-right {
  animation: slideOutToRight var(--transition-slow) ease-in-out forwards;
}

.slideshow-img.slide-in-left {
  animation: slideInFromLeft var(--transition-slow) ease-in-out forwards;
}

.slideshow-img.slide-in-right {
  animation: slideInFromRight var(--transition-slow) ease-in-out forwards;
}

/* ============================================================================
   RESPONSIVE: ORIENTATION-BASED MEDIA QUERIES
   ============================================================================ */

/* Portrait orientation (typically mobile/tablet vertical) */
@media (orientation: portrait) {
  :root {
    --container-padding: var(--spacing-lg);
  }
  
  .nav-links {
    gap: var(--spacing-lg);
  }

  .profile-banner {
    block-size: 140px;
  }

  .profile-photo {
    margin-block-start: -70px;
    inline-size: 140px;
    block-size: 140px;
  }

  .profile-info-container {
    padding-inline: var(--spacing-lg);
    gap: var(--spacing-lg);
  }

  .profile-details {
    padding-block: var(--spacing-md);
  }

  .profile-name {
    font-size: var(--font-size-3xl);
  }

  .profile-title {
    font-size: var(--font-size-base);
  }

  .profile-tagline {
    font-size: var(--font-size-sm);
  }

  .banner-link-item {
    font-size: var(--font-size-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
  }

  .tab-link {
    padding-inline: var(--spacing-lg);
    padding-block: var(--spacing-md);
    font-size: var(--font-size-sm);
  }

  .section-title {
    font-size: var(--font-size-3xl);
  }

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

  .about-container {
    grid-template-columns: 1fr;
  }

  .project-detail-container {
    flex-direction: column;
    gap: var(--spacing-lg);
  }

  .project-detail-left {
    flex: 0 0 auto;
    inline-size: 100%;
  }

  .project-detail-title {
    font-size: var(--font-size-4xl);
  }
}

/* Landscape orientation (typically desktop/tablet horizontal) */
@media (orientation: landscape) and (max-height: 500px) {
  .profile-banner {
    block-size: 140px;
  }

  .profile-photo {
    margin-block-start: -70px;
    inline-size: 120px;
    block-size: 120px;
  }

  .profile-name {
    font-size: var(--font-size-3xl);
  }
}