@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&family=Space+Grotesk:wght@400;500;600;700&display=swap');

:root {
  /* Dark Mode (Default) */
  --bg-dark: #090a0f;
  --bg-surface: #12141c;
  --bg-card: rgba(18, 20, 28, 0.65);
  --bg-card-hover: rgba(26, 29, 41, 0.85);
  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-purple: #9b51e0;
  --accent-error: #ff4757;
  --accent-success: #2ed573;
  --text-bright: #ffffff;
  --text-normal: #b3b8c9;
  --text-muted: #62687c;
  --border-light: rgba(255, 255, 255, 0.06);
  --border-glow: rgba(0, 242, 254, 0.25);
  --font-primary: 'Outfit', sans-serif;
  --font-mono: 'Space Grotesk', sans-serif;
  --transition-smooth: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  --glow-shadow: 0 0 15px rgba(0, 242, 254, 0.15);
  --container-width: 1100px;
}

[data-theme="light"] {
  /* Light Mode */
  --bg-dark: #f5f7fa;
  --bg-surface: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.7);
  --bg-card-hover: rgba(255, 255, 255, 0.9);
  --accent-cyan: #0ea5e9;
  --accent-blue: #2563eb;
  --accent-purple: #7c3aed;
  --accent-error: #ef4444;
  --accent-success: #10b981;
  --text-bright: #0f172a;
  --text-normal: #334155;
  --text-muted: #64748b;
  --border-light: rgba(15, 23, 42, 0.08);
  --border-glow: rgba(37, 99, 230, 0.2);
  --glow-shadow: 0 8px 30px rgba(37, 99, 230, 0.08);
}

/* Reset and Core Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-dark);
  color: var(--text-normal);
  font-family: var(--font-primary);
  line-height: 1.6;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 10% 20%, rgba(37, 99, 230, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 90% 80%, rgba(14, 165, 233, 0.04) 0%, transparent 40%);
  background-attachment: fixed;
  transition: background-color 0.3s ease, color 0.3s ease;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: var(--transition-smooth);
}

a:hover {
  color: var(--text-bright);
}

ul {
  list-style: none;
}

/* Navigation Layout */
header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition-smooth);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 1.2rem 2rem;
}

.logo {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.5rem;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo span {
  color: var(--text-bright);
  -webkit-text-fill-color: var(--text-bright);
  font-size: 0.8rem;
  border: 1px solid var(--border-glow);
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  margin-left: 0.2rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-links a {
  color: var(--text-normal);
  font-weight: 500;
  font-size: 1rem;
  position: relative;
  padding: 0.5rem 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue));
  transition: var(--transition-smooth);
}

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

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

.nav-links a.active {
  color: var(--accent-cyan);
  font-weight: 600;
}

/* Theme Toggle Button */
.theme-toggle-btn {
  background: rgba(15, 23, 42, 0.05);
  border: 1px solid var(--border-light);
  color: var(--text-bright);
  padding: 0.6rem;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-smooth);
}

[data-theme="light"] .theme-toggle-btn {
  background: rgba(15, 23, 42, 0.05);
}

.theme-toggle-btn:hover {
  background: var(--border-light);
}

/* Toggle Sun/Moon Icon display */
/* Default (dark): show sun so user can switch to light */
.theme-toggle-btn .sun-icon {
  display: block;
}
.theme-toggle-btn .moon-icon {
  display: none;
}
/* Light mode: show moon so user can switch to dark */
[data-theme="light"] .theme-toggle-btn .sun-icon {
  display: none;
}
[data-theme="light"] .theme-toggle-btn .moon-icon {
  display: block;
  color: var(--text-bright);
}

/* Mobile Toggle Menu */
.hamburger {
  display: none;
  cursor: pointer;
  background: none;
  border: none;
  flex-direction: column;
  gap: 6px;
}

.hamburger span {
  display: block;
  width: 25px;
  height: 2px;
  background-color: var(--text-bright);
  transition: var(--transition-smooth);
}

/* Layout Containers */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 4rem 2rem;
}

/* Typography elements */
h1, h2, h3, h4 {
  font-family: var(--font-mono);
  color: var(--text-bright);
  font-weight: 700;
}

h1 {
  font-size: 3rem;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
  position: relative;
  display: inline-block;
}

h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 50px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-blue));
  border-radius: 2px;
}

/* Glassmorphic Panel Cards */
.glass-panel {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--border-light);
  border-radius: 16px;
  padding: 2.5rem;
  position: relative;
  overflow: hidden;
}

.glass-panel:hover {
  border-color: var(--border-glow);
  box-shadow: var(--glow-shadow);
}

/* Hero Section (Homepage) */
.hero-section {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
  align-items: center;
  padding: 2rem 2rem 4rem;
}

.hero-content h1 span {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--accent-cyan);
  margin-bottom: 1.5rem;
  font-family: var(--font-mono);
}

.hero-desc {
  font-size: 1.1rem;
  margin-bottom: 2.5rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
}

.btn {
  display: inline-block;
  padding: 0.8rem 1.8rem;
  font-family: var(--font-mono);
  font-weight: 600;
  border-radius: 8px;
  transition: var(--transition-smooth);
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  color: var(--bg-dark);
  border: none;
}

.btn-primary:hover {
  opacity: 0.9;
  color: var(--bg-dark);
}

.btn-secondary {
  background: transparent;
  color: var(--text-bright);
  border: 1px solid var(--border-glow);
}

.btn-secondary:hover {
  background: rgba(0, 242, 254, 0.08);
  border-color: var(--accent-cyan);
}

.hero-image-container {
  display: flex;
  justify-content: center;
  position: relative;
}

.hero-image-wrapper {
  position: relative;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  padding: 8px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  box-shadow: var(--glow-shadow);
}

.hero-image {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--bg-dark);
}

/* Experience Stats Strip */
.stats-strip {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2rem;
  align-items: center;
  margin-top: 4rem;
}

.stats-highlight {
  text-align: center;
  padding: 2rem 2.5rem;
  border-right: 2px solid var(--border-light);
}

.stats-highlight .stat-number {
  font-family: var(--font-mono);
  font-size: 3.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
}

.stats-highlight .stat-label {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-top: 0.3rem;
}

.stats-description {
  padding: 1rem 0;
}

.stats-description p {
  font-size: 1.05rem;
  line-height: 1.8;
}

/* Value Proposition Cards */
.value-props {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 3rem;
}

.value-card {
  text-align: center;
  padding: 2rem 1.5rem;
}

.value-card .value-icon {
  font-size: 2rem;
  margin-bottom: 1rem;
  display: block;
}

.value-card h4 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.value-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* About Me Content */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  margin-top: 2rem;
}

.skills-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1.2rem;
  margin-top: 1rem;
}

.skill-tag {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-light);
  padding: 0.8rem;
  border-radius: 10px;
  text-align: center;
}

.skill-tag:hover {
  background: rgba(0, 242, 254, 0.06);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

.timeline-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1.5rem;
}

.timeline-table th, .timeline-table td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
}

.timeline-table th {
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  font-weight: 600;
}

.timeline-table tr:hover td {
  color: var(--text-bright);
}

/* Projects Section */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.project-thumbnail-wrapper {
  position: relative;
  width: 100%;
  height: 180px;
  overflow: hidden;
  border-radius: 12px;
  margin-bottom: 1.5rem;
  border: 1px solid var(--border-light);
}

.project-thumbnail {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.project-title {
  margin-bottom: 0.8rem;
  font-size: 1.3rem;
}

.project-desc {
  color: var(--text-normal);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.project-tags span {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  padding: 0.2rem 0.6rem;
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.15);
  color: var(--accent-cyan);
  border-radius: 4px;
}

/* Multimedia Video Section */
.multimedia-section {
  margin-top: 4rem;
}

.video-container {
  width: 100%;
  max-width: 800px;
  margin: 2rem auto 0 auto;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--border-glow);
  box-shadow: var(--glow-shadow);
  aspect-ratio: 16 / 9;
  background: #000;
}

.video-container video {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

/* Academic Planner Styling */
.planner-layout {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 3rem;
  align-items: start;
}

.planner-form-section h3 {
  margin-bottom: 1.5rem;
}

.form-group {
  margin-bottom: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.form-group label {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--text-bright);
}

.form-control {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-light);
  border-radius: 8px;
  padding: 0.8rem 1rem;
  color: var(--text-bright);
  font-family: var(--font-primary);
  font-size: 1rem;
  transition: var(--transition-smooth);
  width: 100%;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 10px rgba(0, 242, 254, 0.15);
  background: rgba(255, 255, 255, 0.05);
}

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

.planner-lists-section h3 {
  margin-bottom: 1.5rem;
}

.planner-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-light);
  padding-bottom: 0.5rem;
}

.tab-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-weight: 500;
  cursor: pointer;
  padding: 0.5rem 1rem;
  transition: var(--transition-smooth);
  border-radius: 6px;
}

.tab-btn:hover {
  color: var(--text-bright);
}

.tab-btn.active {
  color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.08);
}

.task-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-height: 450px;
  overflow-y: auto;
  padding-right: 0.5rem;
}

.task-list::-webkit-scrollbar {
  width: 6px;
}

.task-list::-webkit-scrollbar-track {
  background: transparent;
}

.task-list::-webkit-scrollbar-thumb {
  background-color: var(--border-light);
  border-radius: 3px;
}

.task-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-light);
  padding: 1rem 1.2rem;
  border-radius: 10px;
  transition: var(--transition-smooth);
}

.task-item:hover {
  border-color: rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.04);
}

.task-item.priority-high {
  border-left: 4px solid var(--accent-error);
}

.task-item.priority-medium {
  border-left: 4px solid var(--accent-cyan);
}

.task-item.priority-low {
  border-left: 4px solid var(--text-muted);
}

.task-item.completed {
  opacity: 0.5;
  border-left-color: var(--text-muted);
}

.task-item.completed .task-text {
  text-decoration: line-through;
  color: var(--text-muted);
}

.task-info {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  flex-grow: 1;
}

.task-text {
  font-weight: 500;
  color: var(--text-bright);
}

.task-meta {
  display: flex;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.task-meta span {
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.task-actions {
  display: flex;
  gap: 0.5rem;
}

.action-btn {
  background: none;
  border: 1px solid var(--border-light);
  color: var(--text-normal);
  padding: 0.4rem;
  border-radius: 6px;
  cursor: pointer;
  transition: var(--transition-smooth);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
}

.action-btn:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-bright);
}

.action-btn.btn-complete:hover {
  color: var(--accent-success);
  border-color: var(--accent-success);
  background: rgba(46, 213, 115, 0.08);
}

.action-btn.btn-delete:hover {
  color: var(--accent-error);
  border-color: var(--accent-error);
  background: rgba(255, 71, 87, 0.08);
}

.empty-state {
  text-align: center;
  padding: 3rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  border: 1px dashed var(--border-light);
  border-radius: 10px;
}

/* Contact Form and Validation Feedback */
.contact-container {
  max-width: 650px;
  margin: 0 auto;
}

.validation-summary {
  display: none;
  background: rgba(255, 71, 87, 0.1);
  border: 1px solid var(--accent-error);
  color: #ff6b81;
  padding: 1rem 1.2rem;
  border-radius: 8px;
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.validation-summary ul {
  list-style: disc;
  margin-left: 1.5rem;
  margin-top: 0.5rem;
}

.toast-message {
  display: none;
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--bg-surface);
  border: 1px solid var(--accent-success);
  box-shadow: 0 5px 25px rgba(46, 213, 115, 0.2);
  color: #ffffff;
  padding: 1.2rem 2rem;
  border-radius: 10px;
  z-index: 10000;
  display: flex;
  align-items: center;
  gap: 0.8rem;
  font-weight: 500;
  transform: translateY(100px);
  opacity: 0;
  transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity 0.4s ease;
}

.toast-message.show {
  transform: translateY(0);
  opacity: 1;
}

.toast-icon {
  color: var(--accent-success);
  font-size: 1.3rem;
}

/* Footer Section */
footer {
  border-top: 1px solid var(--border-light);
  background: var(--bg-surface);
  padding: 3rem 2rem;
  margin-top: 6rem;
  text-align: center;
  color: var(--text-muted);
}

.footer-content {
  max-width: var(--container-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.footer-student-info {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-normal);
  margin-bottom: 0.5rem;
}

.footer-student-info span {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-light);
  padding: 0.3rem 0.8rem;
  border-radius: 20px;
}

/* Mobile Responsiveness Styles */
@media screen and (max-width: 900px) {
  .hero-section {
    grid-template-columns: 1fr;
    gap: 3rem;
    text-align: center;
    padding: 3rem 1rem;
  }
  
  .hero-image-container {
    order: -1;
  }
  
  .hero-buttons {
    justify-content: center;
  }
  
  .about-grid {
    grid-template-columns: 1fr;
  }
  
  .planner-layout {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .stats-strip {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .stats-highlight {
    border-right: none;
    border-bottom: 2px solid var(--border-light);
    padding-bottom: 1.5rem;
  }

  .value-props {
    grid-template-columns: 1fr;
  }
}

@media screen and (max-width: 768px) {
  .hamburger {
    display: flex;
  }
  
  .nav-links {
    position: fixed;
    top: 68px; /* Height of header */
    right: -100%;
    width: 100%;
    height: calc(100vh - 68px);
    background: var(--bg-surface);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2.5rem;
    transition: 0.4s cubic-bezier(0.77, 0.2, 0.05, 1.0);
    z-index: 999;
  }
  
  .nav-links.active {
    right: 0;
  }
  
  .nav-links a {
    font-size: 1.3rem;
  }
  
  .hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 6px);
  }
  
  .hamburger.active span:nth-child(2) {
    opacity: 0;
  }
  
  .hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -7px);
  }
  
  h1 {
    font-size: 2.3rem;
  }
  
  .timeline-table th, .timeline-table td {
    padding: 0.8rem 0.5rem;
    font-size: 0.9rem;
  }
}