/* ===================================
   Personal Academic Website Styles
   Author: Hamit Efe Çınar
   =================================== */

/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700&family=Playfair+Display:wght@600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* CSS Variables for Color Scheme */
:root {
  --primary-color: #1e3a8a;
  --accent-color: #06b6d4;
  --background-color: #fafaf9;
  --text-primary: #334155;
  --text-secondary: #64748b;
  --white: #ffffff;
  --border-color: #e2e8f0;
  --hover-bg: #f1f5f9;
  
  /* Font families */
  --font-primary: 'Poppins', sans-serif;
  --font-heading: 'Playfair Display', serif;
  --font-mono: 'JetBrains Mono', monospace;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* Border radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
}

/* ===================================
   Base Styles
   =================================== */

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

html {
  font-size: 16px;
}

body {
  font-family: var(--font-primary);
  color: var(--text-primary);
  background-color: var(--background-color);
  line-height: 1.7;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--primary-color);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--spacing-sm);
}

h1 { font-size: 3rem; }
h2 { font-size: 2.25rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1.125rem; }

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

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: all 0.3s ease;
}

a:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

code, pre {
  font-family: var(--font-mono);
  background-color: var(--hover-bg);
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
}

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

/* ===================================
   Navigation
   =================================== */

nav {
  background-color: var(--white);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 2px solid var(--border-color);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-sm) var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-brand {
  font-family: 'Bitcount Grid Single', var(--font-heading);
  font-size: 1.75rem;
  font-weight: 400;
  color: var(--primary-color);
  text-decoration: none;
  letter-spacing: 0.05em;
}

.nav-brand:hover {
  color: var(--accent-color);
  text-decoration: none;
}

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

.nav-menu li {
  display: flex;
  align-items: center;
}

.nav-menu li a {
  color: var(--text-primary);
  font-weight: 500;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: all 0.3s ease;
  text-decoration: none;
  line-height: 1.5;
}

.nav-menu li a:hover,
.nav-menu li a.active {
  background-color: var(--accent-color);
  color: var(--white);
  text-decoration: none;
}

/* Dropdown Menu */
.nav-menu li {
  position: relative;
}

.dropdown {
  position: relative;
}

.dropdown-toggle {
  color: var(--text-primary);
  font-weight: 500;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: all 0.3s ease;
  text-decoration: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  line-height: 1.5;
}

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

.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  background-color: var(--white);
  min-width: 180px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  border-radius: var(--radius-md);
  padding: var(--spacing-xs);
  margin-top: 0.25rem;
  z-index: 1000;
}

.dropdown:hover .dropdown-menu,
.dropdown-menu:hover {
  display: block;
}

/* Keep dropdown visible when hovering over the menu */
.dropdown:hover .dropdown-toggle {
  background-color: var(--accent-color);
  color: var(--white);
}

.dropdown-menu a {
  display: block;
  padding: var(--spacing-sm);
  color: var(--text-primary);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.3s ease;
}

.dropdown-menu a:hover {
  background-color: var(--accent-color);
  color: var(--white);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--primary-color);
  cursor: pointer;
}

/* ===================================
   Container & Layout
   =================================== */

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-xl) var(--spacing-lg);
}

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

.section-title {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-lg);
  position: relative;
  padding-bottom: var(--spacing-sm);
}

.section-title::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 60px;
  height: 4px;
  background: linear-gradient(to right, var(--accent-color), var(--primary-color));
  border-radius: var(--radius-sm);
}

/* ===================================
   Hero Section
   =================================== */

.hero {
  background: linear-gradient(135deg, var(--primary-color) 0%, #2563eb 100%);
  color: var(--white);
  padding: var(--spacing-xl) 0;
  min-height: 60vh;
  display: flex;
  align-items: center;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: var(--spacing-xl);
  align-items: center;
}

.hero-image {
  position: relative;
}

.hero-image img {
  width: 280px;
  height: 280px;
  border-radius: 50%;
  object-fit: cover;
  border: 6px solid var(--white);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.hero-text h1 {
  color: var(--white);
  font-size: 3.5rem;
  margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
  font-size: 1.5rem;
  color: rgba(255, 255, 255, 0.9);
  font-weight: 400;
  margin-bottom: var(--spacing-md);
}

.hero-description {
  font-size: 1.125rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: var(--spacing-lg);
}

.research-link {
  color: rgba(255, 255, 255, 0.95);
  text-decoration: underline;
  text-decoration-color: rgba(255, 255, 255, 0.5);
  text-underline-offset: 3px;
  transition: all 0.3s ease;
}

.research-link:hover {
  color: var(--accent-color);
  text-decoration-color: var(--accent-color);
  text-decoration: underline;
}

.hero-contact {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
  margin-top: var(--spacing-md);
}

.hero-contact a {
  color: var(--white);
  font-size: 1rem;
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

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

.hero-buttons {
  display: flex;
  gap: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.btn {
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  transition: all 0.3s ease;
  cursor: pointer;
  border: 2px solid transparent;
  display: inline-block;
  text-decoration: none;
}

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

.btn-primary:hover {
  background-color: transparent;
  border-color: var(--white);
  color: var(--white);
  text-decoration: none;
}

.btn-secondary {
  background-color: transparent;
  color: var(--white);
  border-color: var(--white);
}

.btn-secondary:hover {
  background-color: var(--white);
  color: var(--primary-color);
  text-decoration: none;
}

/* ===================================
   Cards
   =================================== */

.card {
  background-color: var(--white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
  border: 1px solid var(--border-color);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.card-title {
  color: var(--primary-color);
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
}

.card-meta {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: var(--spacing-sm);
}

.card-description {
  color: var(--text-primary);
  line-height: 1.7;
}

/* ===================================
   Grid Layouts
   =================================== */

.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

/* ===================================
   Education & Timeline
   =================================== */

.timeline {
  position: relative;
  padding-left: var(--spacing-xl);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--accent-color), var(--primary-color));
}

.timeline-item {
  position: relative;
  margin-bottom: var(--spacing-xl);
  padding-left: var(--spacing-lg);
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -38px;
  top: 5px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background-color: var(--accent-color);
  border: 3px solid var(--white);
  box-shadow: 0 0 0 3px var(--accent-color);
}

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

.timeline-title {
  font-size: 1.25rem;
  color: var(--primary-color);
  font-weight: 600;
}

.timeline-title a {
  color: inherit;
  text-decoration: none;
  transition: color 0.3s ease, opacity 0.3s ease;
}

.timeline-title a:hover {
  color: var(--accent-color);
  opacity: 0.9;
}

.timeline-location {
  color: var(--text-secondary);
  font-style: italic;
}

.timeline-date {
  color: var(--accent-color);
  font-weight: 500;
}

.timeline-subtitle {
  color: var(--text-primary);
  margin-bottom: var(--spacing-sm);
}

.timeline-content ul {
  list-style: none;
  padding-left: 0;
}

.timeline-content li {
  padding-left: 1.5rem;
  margin-bottom: var(--spacing-xs);
  position: relative;
}

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

/* ===================================
   Publications
   =================================== */

.publication-item {
  background-color: var(--white);
  padding: var(--spacing-lg);
  border-radius: var(--radius-md);
  border-left: 4px solid var(--accent-color);
  margin-bottom: var(--spacing-md);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.publication-title {
  color: var(--primary-color);
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
}

.publication-authors {
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.publication-authors .me {
  font-weight: 600;
  color: var(--primary-color);
}

.publication-venue {
  color: var(--text-secondary);
  font-style: italic;
}

.publication-status {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 500;
  margin-top: var(--spacing-xs);
}

.status-submitted {
  background-color: #fef3c7;
  color: #92400e;
}

.status-preparation {
  background-color: #dbeafe;
  color: #1e40af;
}

/* ===================================
   Skills & Tags
   =================================== */

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

.skill-category h3 {
  color: var(--primary-color);
  font-size: 1.25rem;
  margin-bottom: var(--spacing-sm);
}

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

.tag {
  background-color: var(--hover-bg);
  color: var(--primary-color);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 500;
  border: 1px solid var(--border-color);
}

/* ===================================
   Awards
   =================================== */

.awards-list {
  list-style: none;
}

.award-item {
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  background-color: var(--white);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--accent-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.award-title {
  color: var(--text-primary);
  font-weight: 500;
}

.award-year {
  color: var(--accent-color);
  font-weight: 600;
}

/* ===================================
   Footer
   =================================== */

footer {
  background-color: var(--primary-color);
  color: var(--white);
  padding: var(--spacing-xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

footer p {
  color: var(--white);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.footer-links {
  display: flex;
  gap: var(--spacing-lg);
  list-style: none;
}

.footer-links a {
  color: var(--white);
  transition: color 0.3s ease;
}

.footer-links a:hover {
  color: var(--accent-color);
  text-decoration: none;
}

.footer-social {
  display: flex;
  gap: var(--spacing-md);
}

.social-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  transition: all 0.3s ease;
  color: var(--white);
  text-decoration: none;
  font-size: 1.25rem;
}

.social-icon:hover {
  background-color: var(--accent-color);
  transform: translateY(-3px);
}

/* ===================================
   Bookshelf
   =================================== */

.bookshelf-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: var(--spacing-lg);
}

.book-card {
  text-align: center;
}

.book-cover {
  width: 100%;
  height: 260px;
  object-fit: cover;
  border-radius: var(--radius-md);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s ease;
}

.book-cover:hover {
  transform: scale(1.05);
}

.book-title {
  margin-top: var(--spacing-sm);
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
}

/* ===================================
   Spotify Embed
   =================================== */

.spotify-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}

.spotify-embed {
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

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

@media (max-width: 768px) {
  html {
    font-size: 14px;
  }
  
  h1 { font-size: 2.5rem; }
  h2 { font-size: 2rem; }
  h3 { font-size: 1.5rem; }
  
  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--white);
    flex-direction: column;
    padding: var(--spacing-md);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  }
  
  .nav-menu.active {
    display: flex;
  }
  
  .mobile-menu-toggle {
    display: block;
  }
  
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-image {
    margin: 0 auto;
  }
  
  .hero-image img {
    width: 200px;
    height: 200px;
  }
  
  .hero-text h1 {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.25rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .hero-contact {
    align-items: center;
  }
  
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }
  
  .timeline {
    padding-left: var(--spacing-md);
  }
  
  .timeline-header {
    flex-direction: column;
  }
  
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
  
  .section-title {
    font-size: 2rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: var(--spacing-md) var(--spacing-sm);
  }
  
  .hero {
    min-height: auto;
  }
  
  .hero-image img {
    width: 150px;
    height: 150px;
  }
  
  .bookshelf-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  }
  
  .book-cover {
    height: 200px;
  }
}

/* ===================================
   Utility Classes
   =================================== */

.text-center {
  text-align: center;
}

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }