/* 🌙 Theme Variables */
:root {
  --primary: #007acc;
  --secondary: #005f99;
  --bg-light: #f9fafb;
  --bg-dark: #121212;
  --text-light: #333;
  --text-dark: #f0f0f0;
  --transition: 0.3s ease-in-out;
}

/* ✅ Typography System */
:root {
  --font-heading: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

/* ✅ Headings */
h1, h2, h3, h4, h5 {
  font-family: var(--font-heading);
  line-height: 1.3;
  letter-spacing: 0.5px;
  margin-top: 0;
  margin-bottom: 10px;
}

h1 {
  font-size: 2.8rem;
  font-weight: 700;
}
h2 {
  font-size: 2rem;
  font-weight: 600;
}
h3 {
  font-size: 1.5rem;
  font-weight: 600;
}

/* ✅ Body */
body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-light);
}

/* ✅ Links */
a {
  text-decoration: none;
  color: var(--primary);
  position: relative;
  transition: color var(--transition);
}
a::after {
  content: '';
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -2px;
  left: 0;
  background: var(--primary);
  transition: width 0.3s ease;
}
a:hover::after {
  width: 100%;
}

/* ✅ Code snippets (future-proof for tech portfolio) */
code {
  font-family: var(--font-mono);
  background: rgba(0,0,0,0.05);
  padding: 2px 4px;
  border-radius: 4px;
  font-size: 0.95rem;
}
body.dark-mode code {
  background: rgba(255,255,255,0.1);
}

/* ✅ Responsive Typography */
@media (max-width: 700px) {
  h1 { font-size: 2.2rem; }
  h2 { font-size: 1.6rem; }
  h3 { font-size: 1.3rem; }
}


body.dark-mode {
  background: var(--bg-dark);
  color: var(--text-dark);
}

/* ✅ Progress Bar */
#progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  background: var(--primary);
  width: 0%;
  z-index: 1000;
  transition: width 0.2s ease-out;
}

/* ✅ Header */
header {
  text-align: center;
  padding: 80px 20px 60px;
  background: var(--primary);
  color: white;
  position: relative;
}

header h1 {
  font-size: 2.8rem;
  margin-bottom: 10px;
}

header h2 {
  font-size: 1.4rem;
  font-weight: 400;
  margin-bottom: 5px;
}

header p {
  font-size: 1rem;
  margin-top: 10px;
}

/* ✅ Dark Mode Button */
.dark-toggle {
  position: absolute;
  top: 20px;
  right: 20px;
  background: white;
  border: none;
  border-radius: 50%;
  width: 45px;
  height: 45px;
  font-size: 20px;
  cursor: pointer;
  box-shadow: 0 2px 5px rgba(0,0,0,0.2);
  transition: transform var(--transition);
}
.dark-toggle:hover {
  transform: scale(1.1);
}
body.dark-mode .dark-toggle {
  background: #333;
  color: white;
}

/* ✅ Social Icons */
.social-icons a {
  margin: 0 10px;
  color: white;
  font-size: 24px;
  transition: color var(--transition);
}
.social-icons a:hover {
  color: #ffdd57;
}

/* ✅ Sections */
section {
  max-width: 950px;
  margin: 40px auto;
  padding: 40px;
  background: white;
  border-radius: 10px;
  box-shadow: 0 3px 12px rgba(0,0,0,0.1);
  transition: transform var(--transition), background var(--transition);
}
section:hover {
  transform: translateY(-3px);
}
body.dark-mode section {
  background: #1e1e1e;
}

h2 {
  text-align: center;
  color: var(--primary);
  margin-bottom: 20px;
  font-weight: 700;
}

/* ✅ Skills */
.skills-list {
  list-style: none;
  padding: 0;
  font-size: 1rem;
}
.skills-list li {
  padding: 8px 0;
}

/* ✅ Timeline */
.timeline {
  border-left: 2px solid #ddd;
  padding-left: 20px;
}
.timeline-item {
  margin-bottom: 20px;
  position: relative;
}
.timeline-item::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 5px;
  width: 12px;
  height: 12px;
  background: var(--primary);
  border-radius: 50%;
}

/* ✅ CTA Section */
.cta {
  text-align: center;
  background: var(--primary);
  color: white;
}
.cta h2 {
  color: white;
}
.cta p {
  margin: 10px auto 20px;
  font-size: 1.1rem;
}
.btn-primary {
  display: inline-block;
  padding: 12px 25px;
  background: white;
  color: var(--primary);
  border-radius: 30px;
  font-weight: bold;
  text-decoration: none;
  transition: background var(--transition), color var(--transition);
}
.btn-primary:hover {
  background: #ffdd57;
  color: #333;
}

/* ✅ Footer */
footer {
  text-align: center;
  padding: 20px;
  background: var(--primary);
  color: white;
  font-size: 14px;
}

/* ✅ Back to Top Button */
#backToTop {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 50%;
  width: 45px;
  height: 45px;
  font-size: 20px;
  cursor: pointer;
  display: none;
  box-shadow: 0 3px 8px rgba(0,0,0,0.3);
  transition: background var(--transition), transform var(--transition);
}
#backToTop:hover {
  background: var(--secondary);
  transform: scale(1.1);
}

/* ✅ Skip Link (Accessibility) */
.skip-link {
  position: absolute;
  top: -40px;
  left: 10px;
  background: #000;
  color: #fff;
  padding: 8px 12px;
  border-radius: 4px;
  transition: top 0.3s;
  z-index: 10000;
}
.skip-link:focus {
  top: 10px;
}

/* ✅ Responsive */
@media (max-width: 700px) {
  header h1 {
    font-size: 2rem;
  }
  section {
    padding: 25px;
    margin: 15px;
  }
}