/* Modern CSS Reset */
*, *::before, *::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, picture, video, canvas, svg {
  display: block;
  max-width: 100%;
}

input, button, textarea, select {
  font: inherit;
}

p, h1, h2, h3, h4, h5, h6 {
  overflow-wrap: break-word;
}

/* CSS Custom Properties */
:root {
  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: "JetBrains Mono", monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Layout */
  --max-width: 680px;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: 500ms cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

/* Dark theme (default) */
[data-theme="dark"] {
  --color-bg: rgb(15 23 42);
  --color-bg-secondary: rgb(30 41 59);
  --color-bg-tertiary: rgb(51 65 85);
  --color-text: #fafafa;
  --color-text-muted: #94a3b8;
  --color-accent-1: rgb(16 185 129);
  --color-accent-2: rgb(16 185 129);
  --color-link: #60a5fa;
  --color-link-hover: #93c5fd;
  --color-border: rgb(51 65 85);
  --color-glow: rgba(16, 185, 129, 0.15);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 30px rgba(16, 185, 129, 0.2);
}

/* Light theme */
[data-theme="light"] {
  --color-bg: #f5f3f0;
  --color-bg-secondary: #ebe8e4;
  --color-bg-tertiary: #dedad5;
  --color-text: #1a1918;
  --color-text-muted: #5c5856;
  --color-accent-1: #059669;
  --color-accent-2: #059669;
  --color-link: #7c3aed;
  --color-link-hover: #6d28d9;
  --color-border: #d6d2cc;
  --color-glow: rgba(5, 150, 105, 0.12);
  --shadow-sm: 0 2px 8px rgba(26, 25, 24, 0.06);
  --shadow-md: 0 4px 20px rgba(26, 25, 24, 0.1);
  --shadow-glow: 0 0 30px rgba(5, 150, 105, 0.2);
}

/* Base styles */
body {
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  font-weight: 450;
  background-color: var(--color-bg);
  color: var(--color-text);
  transition: background-color var(--transition-normal), color var(--transition-normal);
  min-height: 100vh;
  letter-spacing: -0.01em;
}


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

main {
  padding: var(--space-3xl) 0;
}

/* Typography */
h1, h2, h3 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 {
  font-family: var(--font-sans);
  font-size: 3.25rem;
  font-weight: 800;
  color: var(--color-accent-1);
}

h2 {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--color-accent-1);
  margin-bottom: var(--space-xl);
}

h3 {
  font-size: 1.125rem;
  margin-bottom: var(--space-sm);
}

p {
  margin-bottom: var(--space-md);
  color: var(--color-text-muted);
}

/* Links with animated underline */
.highlight {
  font-weight: 700;
  color: var(--color-accent-1);
}

a {
  color: var(--color-link);
  text-decoration: none;
  position: relative;
  transition: color var(--transition-fast);
}

a:not(.social-links a):not(.theme-toggle)::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent-1);
  transition: width var(--transition-normal);
}

a:not(.social-links a):not(.theme-toggle):hover::after {
  width: 100%;
}

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

/* Header */
.site-header {
  position: fixed;
  top: 0;
  right: 0;
  padding: var(--space-lg);
  z-index: 100;
}

/* Theme toggle */
.theme-toggle {
  background: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: var(--space-sm) var(--space-md);
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.theme-toggle:hover {
  background: var(--color-bg-tertiary);
  color: var(--color-text);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.theme-toggle:active {
  transform: translateY(0);
}

/* Hero section */
.hero {
  padding: var(--space-3xl) 0 var(--space-xl);
}

.hero h1 {
  margin-bottom: var(--space-xs);
  animation: fadeInUp 0.6s ease-out;
}

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

.subtitle-row {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  animation: fadeInUp 0.6s ease-out 0.1s both;
  font-weight: bold;
}

.hero .subtitle {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--color-text-muted);
  margin-bottom: 0;
}

.subtitle {
  font-weight: bold;
}

.social-links {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  color: var(--color-text-muted);
  background: var(--color-bg-secondary);
  transition: all var(--transition-fast);
}

.social-links a:hover {
  color: var(--color-text);
  background: var(--color-bg-tertiary);
  transform: translateY(-3px) scale(1.05);
  box-shadow: var(--shadow-md);
}

.social-links svg {
  width: 18px;
  height: 18px;
}

.hero .intro {
  font-size: 1.1875rem;
  line-height: 1.7;
  color: var(--color-text-muted);
  max-width: 560px;
  animation: fadeInUp 0.6s ease-out 0.2s both;
}

/* Sections */
.section {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--color-border);
}

.section-header {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-xl);
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
}

.section-header::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--color-accent-1);
  border-radius: 2px;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.7; transform: scale(0.9); }
}

/* About items */
.about-item {
  margin-bottom: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  overflow: hidden;
  background: var(--color-bg-secondary);
  transition: all var(--transition-normal);
}

.about-item:hover {
  border-color: var(--color-accent-1);
  box-shadow: var(--shadow-glow);
}

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

.about-header {
  display: flex;
  align-items: center;
  padding: var(--space-lg);
  cursor: pointer;
  list-style: none;
  font-weight: 600;
  color: var(--color-text);
  background: transparent;
  transition: background-color var(--transition-fast);
}

.about-header::-webkit-details-marker {
  display: none;
}

.about-header:hover {
  background: var(--color-bg-tertiary);
}

.about-content {
  padding: 0 var(--space-lg) var(--space-lg);
}

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

/* CTA Section */
.section--cta {
  padding: 0 0 var(--space-xl);
  border-top: none;
  border-bottom: none;
}

.cta-title {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-accent-1);
  margin-bottom: var(--space-sm);
}

.cta-box {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  padding: var(--space-lg);
  border: 2px dashed var(--color-accent-1);
  border-radius: 16px;
  background: var(--color-bg-secondary);
}

.cta-icon {
  color: var(--color-accent-1);
  font-size: 1.25rem;
  line-height: 1.6;
}

.cta-box p {
  margin: 0;
}

/* Experience items */
.experience-item {
  margin-bottom: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  overflow: hidden;
  background: var(--color-bg-secondary);
  transition: all var(--transition-normal);
}

.experience-item:hover {
  border-color: var(--color-accent-1);
  box-shadow: var(--shadow-glow);
}

.experience-item:last-child {
  margin-bottom: 0;
}

.experience-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-lg);
  cursor: pointer;
  list-style: none;
  background: transparent;
  transition: background-color var(--transition-fast);
}

.experience-header::-webkit-details-marker {
  display: none;
}

.experience-header:hover {
  background: var(--color-bg-tertiary);
}

.experience-title {
  font-weight: 600;
  color: var(--color-text);
}

.experience-company {
  color: var(--color-text-muted);
}

.experience-date {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-left: auto;
  padding: var(--space-xs) var(--space-sm);
  background: var(--color-bg-tertiary);
  border-radius: 6px;
}

.experience-content {
  padding: 0 var(--space-lg) var(--space-lg);
}

.experience-description {
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Tags */
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  padding: var(--space-xs) var(--space-sm);
  border-radius: 6px;
  background: var(--color-bg-tertiary);
  color: var(--color-text-muted);
  transition: all var(--transition-fast);
}

.tag:hover {
  background: var(--color-accent-1);
  color: white;
  transform: translateY(-2px);
}

.tag::before,
.tag::after {
  display: none;
}

/* Coming soon placeholder */
.coming-soon {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  padding: var(--space-lg);
  border: 2px dashed var(--color-border);
  border-radius: 12px;
  text-align: center;
}

/* Footer */
.site-footer {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--color-border);
}

.footer-copy {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* Responsive */
@media (max-width: 640px) {
  h1 {
    font-size: 2.25rem;
  }

  .hero {
    padding-top: var(--space-2xl);
  }

  .subtitle-row {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
  }

  .hero .subtitle {
    font-size: 0.9rem;
  }

  .experience-header {
    flex-direction: column;
    align-items: flex-start;
    position: relative;
    padding-right: calc(var(--space-lg) + 28px);
  }

  .experience-header::before {
    position: absolute;
    right: var(--space-lg);
    top: var(--space-lg);
  }

  .experience-header::after {
    left: auto;
    right: calc(var(--space-lg) + 7px);
    top: calc(var(--space-lg) + 7px);
  }

  .experience-date {
    margin-left: 0;
    margin-top: var(--space-xs);
  }

  .experience-content {
    padding-left: var(--space-lg);
  }
}