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

:root {
  --color-bg: #fafafa;
  --color-bg-alt: #ffffff;
  --color-text: #1a1a1a;
  --color-text-secondary: #666666;
  --color-accent: #0d9488;
  --color-accent-dark: #0f766e;
  --color-accent-light: #14b8a6;
  --color-border: #e5e5e5;
  --color-border-dark: #d4d4d4;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --max-width: 720px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 5rem;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

/* Typography */
h1, h2, h3 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-text);
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: var(--spacing-lg);
}

h3 {
  font-size: 1.125rem;
  font-weight: 600;
}

p {
  margin-bottom: var(--spacing-sm);
}

strong {
  font-weight: 600;
  color: var(--color-text);
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover, a:focus {
  color: var(--color-accent-dark);
}

ul {
  list-style: none;
}

/* Header */
.header {
  padding: var(--spacing-2xl) 0 var(--spacing-xl);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg-alt);
}

.name {
  margin-bottom: var(--spacing-xs);
  color: var(--color-text);
}

.title {
  color: var(--color-text-secondary);
  font-size: 1.0625rem;
  margin-bottom: var(--spacing-lg);
  font-weight: 400;
}

.nav {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
}

.nav a {
  color: var(--color-text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  padding: var(--spacing-xs) 0;
  border-bottom: 2px solid transparent;
  transition: all 0.15s ease;
}

.nav a:hover, .nav a:focus {
  color: var(--color-text);
  border-bottom-color: var(--color-accent);
}

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

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

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

/* About */
.about-content {
  font-size: 1.0625rem;
  color: var(--color-text-secondary);
  max-width: 600px;
}

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

/* Stats Grid */
.stats-grid {
  display: flex;
  gap: var(--spacing-xl);
  margin-top: var(--spacing-xl);
  flex-wrap: wrap;
}

.stat {
  text-align: left;
}

.stat-value {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-accent);
  display: block;
  line-height: 1;
  letter-spacing: -0.02em;
}

.stat-label {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  margin-top: var(--spacing-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Skills Grid */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-xl);
}

.skill-group h3 {
  margin-bottom: var(--spacing-sm);
  font-size: 0.9375rem;
  color: var(--color-text);
  padding-bottom: var(--spacing-xs);
  border-bottom: 2px solid var(--color-accent);
  display: inline-block;
}

.skill-group ul {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.skill-group li {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
}

/* Jobs */
.job {
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-xl);
  border-bottom: 1px solid var(--color-border);
}

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

.job.featured {
  position: relative;
  padding-left: var(--spacing-md);
  border-left: 3px solid var(--color-accent);
  border-bottom: 1px solid var(--color-border);
}

.job-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.job-header h3 {
  margin-bottom: 0.125rem;
}

.company {
  color: var(--color-accent);
  font-size: 0.9375rem;
  font-weight: 500;
}

.date {
  color: var(--color-text-secondary);
  font-size: 0.8125rem;
  white-space: nowrap;
}

.achievements {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
}

.achievements li {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  padding-left: var(--spacing-md);
  position: relative;
  line-height: 1.6;
}

.achievements li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.625rem;
  width: 5px;
  height: 1px;
  background: var(--color-border-dark);
}

/* Certifications */
.certs-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.cert {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-xs) var(--spacing-sm);
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  font-size: 0.875rem;
}

.cert-badge {
  font-weight: 600;
  color: var(--color-accent);
}

.cert-name {
  color: var(--color-text-secondary);
}

/* Education */
.education-item h3 {
  margin-bottom: 0.125rem;
}

.education-item p {
  color: var(--color-text-secondary);
  margin-bottom: 0;
  font-size: 0.9375rem;
}

/* Contact */
#contact .container {
  max-width: 500px;
}

.contact-text {
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-md);
}

.contact-btn {
  display: inline-block;
  background: var(--color-accent);
  color: white;
  padding: 0.75rem 1.5rem;
  font-weight: 500;
  font-size: 0.9375rem;
  transition: background 0.15s ease;
}

.contact-btn:hover, .contact-btn:focus {
  background: var(--color-accent-dark);
  color: white;
}

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

.footer p {
  color: var(--color-text-secondary);
  font-size: 0.8125rem;
  margin: 0;
}

/* Responsive */
@media (max-width: 640px) {
  h1 { font-size: 1.875rem; }

  .header {
    padding: var(--spacing-xl) 0;
  }

  .section {
    padding: var(--spacing-xl) 0;
  }

  .job-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.25rem;
  }

  .job.featured {
    padding-left: var(--spacing-sm);
  }

  .skills-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }

  .stats-grid {
    gap: var(--spacing-lg);
  }

  .stat-value {
    font-size: 2rem;
  }

  .nav {
    gap: var(--spacing-sm);
  }
}

/* Print styles */
@media print {
  .nav, .contact-btn {
    display: none;
  }

  .section {
    padding: var(--spacing-md) 0;
    border-bottom: none;
  }

  .job {
    break-inside: avoid;
  }
}

/* Focus styles for accessibility */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *, *::before, *::after {
    transition: none !important;
  }
}

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