/* ============================================
   APPLE-CLEAN PORTFOLIO STYLES
   Mobile-first, minimal, with subtle animations
   ============================================ */

/* CSS Variables - 8px spacing scale */
:root {
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-text: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-border: #d2d2d7;
  --color-primary: #1d1d1f;
  --color-primary-hover: #000000;
  --color-accent: #0071e3;
  
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 32px;
  --spacing-xl: 48px;
  --spacing-2xl: 64px;
  --spacing-3xl: 96px;
  
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1100px;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

/* ============================================
   NAVIGATION
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: rgba(250, 250, 250, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: var(--transition);
}

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

.nav-logo {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text);
  text-decoration: none;
  transition: var(--transition);
}

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

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
  align-items: center;
}

.nav-link {
  color: var(--color-text);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  padding: var(--spacing-xs) 0;
  position: relative;
  transition: var(--transition);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-accent);
  transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

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

.nav-link.active {
  color: var(--color-accent);
}

/* Hamburger Menu */
.nav-toggle {
  display: none;
  flex-direction: column;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
  gap: 5px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  transition: var(--transition);
  border-radius: 2px;
}

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--spacing-3xl) var(--spacing-md) var(--spacing-2xl);
  margin-top: 60px;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
  animation: fadeInUp 0.8s ease-out;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  color: var(--color-text-secondary);
  max-width: 700px;
  margin: 0 auto var(--spacing-xl);
  line-height: 1.5;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-buttons {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-block;
  padding: 12px 32px;
  font-size: 1rem;
  font-weight: 500;
  text-decoration: none;
  border-radius: var(--radius-lg);
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.btn-primary {
  background-color: var(--color-primary);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background-color: var(--color-primary-hover);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-text);
  border: 1.5px solid var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--color-text);
  background-color: var(--color-surface);
  transform: translateY(-2px);
}

/* ============================================
   SECTIONS
   ============================================ */
.section {
  padding: var(--spacing-3xl) 0;
}

.section-title {
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-xl);
  text-align: center;
  color: var(--color-text);
}

/* ============================================
   ABOUT SECTION
   ============================================ */
.about-text {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  max-width: 800px;
  margin: 0 auto var(--spacing-xl);
  text-align: center;
  line-height: 1.7;
}

.highlights {
  list-style: none;
  max-width: 900px;
  margin: 0 auto;
  display: grid;
  gap: var(--spacing-md);
}

.highlights li {
  background-color: var(--color-surface);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-sm);
  transition: var(--transition);
}

.highlights li:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
  border-color: var(--color-text);
}

.highlight-icon {
  font-size: 1.5rem;
  flex-shrink: 0;
}

.highlights strong {
  color: var(--color-text);
}

/* ============================================
   PROJECTS SECTION
   ============================================ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.project-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.project-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-8px);
  border-color: var(--color-text);
}

.project-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

.project-description {
  color: var(--color-text-secondary);
  line-height: 1.6;
  flex-grow: 1;
  margin-bottom: var(--spacing-sm);
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-sm);
}

.tag {
  background-color: var(--color-bg);
  color: var(--color-text-secondary);
  padding: 4px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid var(--color-border);
}

.project-links {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
  padding-top: var(--spacing-sm);
  border-top: 1px solid var(--color-border);
}

.project-link {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-accent);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: var(--transition);
}

.project-link:hover {
  color: var(--color-text);
}

.project-link svg {
  flex-shrink: 0;
}

/* ============================================
   WORK/EXPERIENCE SECTION
   ============================================ */
.work-timeline {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.work-item {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  transition: var(--transition);
  position: relative;
}

.work-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateX(8px);
  border-color: var(--color-text);
}

.work-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background-color: var(--color-accent);
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  opacity: 0;
  transition: var(--transition);
}

.work-item:hover::before {
  opacity: 1;
}

.work-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: var(--spacing-xs);
  flex-wrap: wrap;
  gap: var(--spacing-xs);
}

.work-role {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text);
}

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

.work-company {
  color: var(--color-accent);
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: var(--spacing-sm);
}

.work-description {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.work-description li {
  color: var(--color-text-secondary);
  padding-left: var(--spacing-md);
  position: relative;
}

.work-description li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--color-accent);
  font-weight: bold;
}

/* ============================================
   CONTACT SECTION
   ============================================ */
.contact-intro {
  text-align: center;
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xl);
}

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

.contact-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm) var(--spacing-md);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
}

.contact-link:hover {
  border-color: var(--color-text);
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.contact-link svg {
  flex-shrink: 0;
}

/* Contact Form */
.contact-form {
  max-width: 600px;
  margin: 0 auto;
  background-color: var(--color-surface);
  padding: var(--spacing-xl);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-group label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 500;
  color: var(--color-text);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 1rem;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

.error-message {
  display: block;
  color: #ff3b30;
  font-size: 0.875rem;
  margin-top: var(--spacing-xs);
  min-height: 20px;
}

.form-success {
  color: #34c759;
  font-weight: 500;
  margin-top: var(--spacing-sm);
  text-align: center;
  min-height: 24px;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
  margin-top: var(--spacing-3xl);
  text-align: center;
}

.footer p {
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

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

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

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

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

/* Tablets and below */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  
  .nav-menu {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background-color: rgba(250, 250, 250, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    padding: var(--spacing-md);
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s ease;
  }
  
  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  .nav-menu li {
    width: 100%;
    text-align: center;
    border-bottom: 1px solid var(--color-border);
  }
  
  .nav-menu li:last-child {
    border-bottom: none;
  }
  
  .nav-link {
    display: block;
    padding: var(--spacing-sm);
  }
  
  .hero {
    min-height: 80vh;
    padding: var(--spacing-2xl) var(--spacing-md);
  }
  
  .projects-grid {
    grid-template-columns: 1fr;
  }
  
  .work-header {
    flex-direction: column;
  }
  
  .contact-links {
    flex-direction: column;
    align-items: stretch;
  }
  
  .contact-link {
    justify-content: center;
  }
  
  .contact-form {
    padding: var(--spacing-md);
  }
}

/* Mobile phones */
@media (max-width: 480px) {
  html {
    font-size: 14px;
  }
  
  .section {
    padding: var(--spacing-2xl) 0;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: stretch;
  }
  
  .btn {
    width: 100%;
    text-align: center;
  }
}

/* Smooth scrolling offset for fixed nav */
section {
  scroll-margin-top: 80px;
}