/* Global Variables & Theme */
:root {
  /* Light Theme (Default) */
  --bg-color: #f4f4f9;
  --text-color: #333333;
  --card-bg: #ffffff;
  --primary-color: #00bcd4;
  --secondary-color: #008ba3;
  --accent-color: #ff4081;
  --nav-bg: rgba(255, 255, 255, 0.9);
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --transition-speed: 0.3s;
  --font-main: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
  /* Dark Theme */
  --bg-color: #121212;
  --text-color: #e0e0e0;
  --card-bg: #1e1e1e;
  --primary-color: #00bcd4;
  --secondary-color: #00e5ff;
  --accent-color: #ff80ab;
  --nav-bg: rgba(18, 18, 18, 0.9);
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
}

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: background-color var(--transition-speed), color var(--transition-speed);
  overflow-x: hidden;
}

html {
  scroll-behavior: smooth;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition-speed);
}

ul {
  list-style: none;
}

/* Typography */
h1,
h2,
h3 {
  font-weight: 700;
  margin-bottom: 1rem;
}

h1 {
  font-size: 2.5rem;
}

h2 {
  font-size: 2rem;
  color: var(--primary-color);
}

h3 {
  font-size: 1.5rem;
}

p {
  margin-bottom: 1rem;
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: var(--nav-bg);
  backdrop-filter: blur(10px);
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  z-index: 1000;
  box-shadow: var(--shadow);
}

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

.nav-links a {
  font-weight: 500;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -5px;
  left: 0;
  background-color: var(--primary-color);
  transition: width 0.3s;
}

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

.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
}

.hamburger .bar {
  width: 25px;
  height: 3px;
  background-color: var(--text-color);
  transition: all 0.3s;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--primary-color);
}

.nav-controls {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.btn-toggle {
  background: none;
  border: 2px solid var(--primary-color);
  color: var(--primary-color);
  padding: 0.5rem 1rem;
  border-radius: 20px;
  cursor: pointer;
  font-weight: 600;
  transition: all var(--transition-speed);
}

.btn-toggle:hover {
  background: var(--primary-color);
  color: #fff;
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 2rem;
  padding-top: 80px;
  /* Offset for fixed nav */
  background: radial-gradient(circle at center, var(--card-bg) 0%, var(--bg-color) 100%);
}

.hero-logo {
  width: 150px;
  height: auto;
  margin-bottom: 1.5rem;
  filter: drop-shadow(0 0 10px var(--primary-color));
  animation: float 4s ease-in-out infinite;
}

.hero h1 {
  margin-bottom: 0.5rem;
}

.tagline {
  font-size: 1.2rem;
  color: var(--secondary-color);
  margin-bottom: 2rem;
}

/* Sections */
section {
  padding: 4rem 2rem;
  max-width: 1100px;
  margin: 0 auto;
}

.section-content {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.section-content.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Skills/Interests */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1.5rem;
  text-align: center;
}

.skill-card {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 10px;
  box-shadow: var(--shadow);
  transition: transform var(--transition-speed);
}

.skill-card:hover {
  transform: translateY(-5px);
}

.skill-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 0.5rem;
}

/* Contact & Footer */
.footer {
  background: var(--card-bg);
  padding: 3rem 2rem;
  text-align: center;
  border-top: 1px solid var(--primary-color);
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.social-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--bg-color);
  font-size: 1.5rem;
  color: var(--text-color);
  box-shadow: var(--shadow);
  transition: all var(--transition-speed);
}

.social-btn:hover {
  background: var(--primary-color);
  color: #fff;
  transform: scale(1.1);
  box-shadow: 0 0 15px var(--primary-color);
}

.footer-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.email-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.1rem;
  color: var(--text-color);
  font-weight: 500;
}

.email-link:hover {
  color: var(--primary-color);
}

.copyright {
  font-size: 0.9rem;
  opacity: 0.8;
}

/* Animations */
@keyframes float {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-10px);
  }
}

/* Responsive */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .navbar {
    padding: 1rem;
  }

  .nav-controls {
    gap: 0.5rem;
  }

  .btn-toggle {
    padding: 0.4rem 0.8rem;
    font-size: 0.9rem;
  }

  /* Mobile Nav */
  .hamburger {
    display: flex;
    z-index: 1001;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 70%;
    height: 100vh;
    background: var(--card-bg);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    transition: right 0.3s ease-in-out;
    box-shadow: -5px 0 15px rgba(0, 0, 0, 0.1);
    z-index: 1000;
  }

  .nav-links.active {
    right: 0;
  }

  .nav-links a {
    font-size: 1.2rem;
  }

  /* Hamburger Animation */
  .hamburger.active .bar:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }

  .hamburger.active .bar:nth-child(2) {
    opacity: 0;
  }

  .hamburger.active .bar:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }
}

/* Dark Mode Logo Adjustment */
[data-theme="dark"] .hero-logo {
  filter: drop-shadow(0 0 10px var(--primary-color)) brightness(0) invert(1);
}

/* Back to Top Button */
#back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: var(--primary-color);
  color: #fff;
  border: none;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  font-size: 1.2rem;
  cursor: pointer;
  box-shadow: var(--shadow);
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease-in-out;
  z-index: 900;
  display: flex;
  align-items: center;
  justify-content: center;
}

#back-to-top.visible {
  opacity: 1;
  visibility: visible;
  animation: float 2s ease-in-out infinite;
}

#back-to-top:hover {
  background: var(--secondary-color);
  transform: translateY(-5px);
}