/* Custom Properties (Variables) */
:root {
    --bg-color-dark: #121212; --text-dark: #e0e0e0; --surface-dark: #1a1a1a;
    --bg-color-light: #f5f5f5; --text-light: #212121; --surface-light: #ffffff;
    
    --primary-accent: #8A2BE2; --secondary-accent: #DC143C;
    --border-color: #282828; --border-color-light: #e0e0e0;
    --gradient-text: linear-gradient(135deg, var(--primary-accent), var(--secondary-accent));
    
    --bg-color: var(--bg-color-dark);
    --text-color: var(--text-dark);
    --secondary-text: #b0b0b0;
    --surface-color: var(--surface-dark);
    --current-border: var(--border-color);
}
html.light-theme {
    --bg-color: var(--bg-color-light);
    --text-color: var(--text-light);
    --secondary-text: #555;
    --surface-color: var(--surface-light);
    --current-border: var(--border-color-light);
}

/* Reset and Base Styles */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Poppins', sans-serif; background-color: var(--bg-color); color: var(--text-color); line-height: 1.6; overflow-x: hidden; transition: background-color 0.3s, color 0.3s; }

/* Navigation */
.navbar { position: fixed; top: 0; width: 100%; background: rgba(18, 18, 18, 0.8); backdrop-filter: blur(10px); z-index: 1000; padding: 1rem 0; transition: all 0.3s ease; border-bottom: 1px solid #222; }
html.light-theme .navbar { background: rgba(255, 255, 255, 0.8); border-bottom: 1px solid var(--current-border); }
.nav-container { max-width: 1200px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; padding: 0 2rem; }
.logo { font-size: 1.5rem; font-weight: 700; color: var(--primary-accent); text-decoration: none; }
.nav-menu { display: flex; list-style: none; gap: 2rem; align-items: center; }
.nav-link { color: var(--text-color); text-decoration: none; font-weight: 500; transition: color 0.3s ease; position: relative; }
.nav-link:hover { color: var(--primary-accent); }
.nav-link::after { content: ''; position: absolute; width: 0; height: 2px; bottom: -5px; left: 0; background-color: var(--primary-accent); transition: width 0.3s ease; }
.nav-link:hover::after { width: 100%; }
.hamburger { display: none; flex-direction: column; cursor: pointer; gap: 4px; }
.hamburger span { width: 25px; height: 3px; background: var(--primary-accent); transition: 0.3s; border-radius: 2px; }
.theme-toggle-btn { background: none; border: none; cursor: pointer; font-size: 1.5rem; padding: 0; line-height: 1; }
.theme-toggle-btn .icon-sun { display: none; } html.light-theme .theme-toggle-btn .icon-sun { display: inline; }
html.light-theme .theme-toggle-btn .icon-moon { display: none; }

/* Hero Section */
.hero { min-height: 100vh; display: flex; align-items: center; justify-content: center; position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0; background: radial-gradient(circle at 20% 80%, rgba(138, 43, 226, 0.1) 0%, transparent 40%), radial-gradient(circle at 80% 20%, rgba(220, 20, 60, 0.1) 0%, transparent 40%); }
.hero-content { text-align: center; z-index: 2; max-width: 800px; padding: 0 2rem; }
.hero-title { font-size: 3.5rem; font-weight: 700; background: var(--gradient-text); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-alias { font-size: 1.5rem; font-weight: 300; color: var(--secondary-text); margin-bottom: 1rem; }
.hero .subtitle { font-size: 1.5rem; color: var(--secondary-text); margin-bottom: 2rem; font-weight: 300; min-height: 2.2rem; }
.cta-button { display: inline-block; padding: 1rem 2rem; background: var(--gradient-text); color: white; text-decoration: none; border-radius: 50px; font-weight: 600; transition: transform 0.3s ease, box-shadow 0.3s ease; border: none; cursor: pointer; }
.cta-button:hover { transform: translateY(-3px); box-shadow: 0 10px 30px rgba(138, 43, 226, 0.3); }
.scroll-indicator { position: absolute; bottom: 2rem; left: 50%; color: var(--primary-accent); font-size: 2rem; animation: bounce 2s infinite; text-decoration: none; transform: translateX(-50%); }
@keyframes bounce { 0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); } 40% { transform: translateX(-50%) translateY(-10px); } 60% { transform: translateX(-50%) translateY(-5px); } }

/* Section Styles */
.section { padding: 6rem 2rem; max-width: 1200px; margin: 0 auto; opacity: 0; transform: translateY(40px); transition: opacity 0.8s ease-out, transform 0.8s ease-out; }
.section.visible { opacity: 1; transform: translateY(0); }
.section-title { font-size: 2.5rem; font-weight: 700; text-align: center; margin-bottom: 4rem; color: var(--primary-accent); position: relative; }
.section-title::after { content: ''; position: absolute; bottom: -10px; left: 50%; transform: translateX(-50%); width: 80px; height: 3px; background: var(--gradient-text); border-radius: 2px; }

/* About Section */
.about-content { display: grid; grid-template-columns: auto 1fr; gap: 4rem; align-items: center; }
.about-images img { width: 250px; height: 250px; border-radius: 50%; object-fit: cover; border: 4px solid var(--primary-accent); transition: transform 0.3s ease; }
.about-images img:hover { transform: scale(1.05); }
.about-text p { font-size: 1.1rem; line-height: 1.8; color: var(--secondary-text); margin-bottom: 1rem; }
.cv-button { margin-top: 1rem; }

/* Experience Section (Timeline) */
.timeline { position: relative; max-width: 800px; margin: 0 auto; }
.timeline::after { content: ''; position: absolute; width: 3px; background: var(--primary-accent); top: 0; bottom: 0; left: 50%; margin-left: -1.5px; }
.timeline-item { padding: 1rem 3rem; position: relative; width: 50%; }
.timeline-item:nth-child(odd) { left: 0; text-align: right; }
.timeline-item:nth-child(even) { left: 50%; text-align: left; }
.timeline-icon { position: absolute; width: 50px; height: 50px; right: -25px; background: var(--gradient-text); top: 15px; border-radius: 50%; z-index: 1; display: flex; justify-content: center; align-items: center; font-size: 1.5rem; }
.timeline-item:nth-child(even) .timeline-icon { left: -25px; }
.timeline-content { padding: 1.5rem; background: var(--surface-color); position: relative; border-radius: 8px; border: 1px solid var(--current-border); }
.timeline-date { color: var(--primary-accent); font-weight: 600; margin-bottom: 0.5rem; }

/* Skills Section */
.skills-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 1.5rem; text-align: center; }
.skill-card { background: var(--surface-color); padding: 1.5rem; border-radius: 10px; border: 1px solid var(--current-border); transition: transform 0.3s ease, box-shadow 0.3s ease; }
.skill-card:hover { transform: translateY(-5px); box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2); }
.skill-card i { font-size: 3rem; color: var(--primary-accent); }
.skill-card span { display: block; margin-top: 1rem; font-weight: 500; color: var(--text-color); }

/* Projects Section */
.projects-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: 2rem; }
.project-card { background: var(--surface-color); border-radius: 15px; padding: 2rem; transition: transform 0.3s ease, box-shadow 0.3s ease; border: 1px solid var(--current-border); position: relative; overflow: hidden; display: flex; flex-direction: column; }
.project-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: var(--gradient-text); }
.project-card:hover { transform: translateY(-10px); box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2); }
.project-title { font-size: 1.3rem; font-weight: 600; color: var(--primary-accent); margin-bottom: 1rem; }
.project-description { color: var(--secondary-text); line-height: 1.6; flex-grow: 1; }
.project-tech { display: flex; flex-wrap: wrap; gap: 0.5rem; margin: 1.5rem 0; }
.tech-tag { background: rgba(138, 43, 226, 0.2); color: var(--primary-accent); padding: 0.3rem 0.8rem; border-radius: 20px; font-size: 0.8rem; font-weight: 500; }
.project-links { display: flex; gap: 1rem; margin-top: auto; }
.project-link { text-decoration: none; font-weight: 600; transition: color 0.3s ease; color: var(--secondary-text); }
.project-link:hover { color: var(--primary-text); }
.project-link.online { color: var(--primary-accent); }
.project-link.online:hover { color: var(--secondary-accent); }

/* Contact Section */
.contact-content { text-align: center; max-width: 600px; margin: 0 auto; }
.contact-content p { font-size: 1.2rem; color: var(--secondary-text); }
#contact-form { display: flex; flex-direction: column; gap: 1rem; margin-top: 2rem; }
#contact-form input, #contact-form textarea { width: 100%; padding: 1rem; border-radius: 8px; border: 1px solid var(--current-border); background: var(--surface-color); color: var(--text-color); font-family: 'Poppins', sans-serif; font-size: 1rem; }
#contact-form textarea { min-height: 150px; resize: vertical; }
#form-status { margin-top: 1rem; font-weight: 500; min-height: 1.5rem; }

/* Back to Top Button */
.back-to-top-btn { position: fixed; bottom: 2rem; right: 2rem; background: var(--gradient-text); color: white; width: 50px; height: 50px; border-radius: 50%; display: flex; justify-content: center; align-items: center; font-size: 1.5rem; text-decoration: none; z-index: 100; opacity: 0; visibility: hidden; transition: opacity 0.3s, visibility 0.3s, transform 0.3s; }
.back-to-top-btn.visible { opacity: 1; visibility: visible; }
.back-to-top-btn:hover { transform: scale(1.1); }

/* Footer */
.footer { background: #0a0a0a; text-align: center; padding: 3rem 2rem 2rem; color: #666; border-top: 1px solid #222; }
html.light-theme .footer { background: var(--surface-light); }
.footer-socials { display: flex; justify-content: center; gap: 1.5rem; margin-bottom: 1.5rem; }
.footer-socials a { color: var(--secondary-text); font-size: 2rem; transition: color 0.3s ease, transform 0.3s ease; }
.footer-socials a:hover { color: var(--primary-accent); transform: translateY(-5px); }

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger { display: flex; }
    .nav-menu { position: fixed; left: -100%; top: 65px; flex-direction: column; background-color: rgba(18, 18, 18, 0.98); width: 100%; text-align: center; transition: 0.3s; padding: 2rem 0; gap: 1rem; }
    html.light-theme .nav-menu { background-color: rgba(255, 255, 255, 0.98); }
    .nav-menu.active { left: 0; }
    .hero-title { font-size: 2.5rem; }
    .hero .subtitle { font-size: 1.2rem; }
    .section { padding: 4rem 1rem; }
    .section-title { font-size: 2rem; }
    .about-content { grid-template-columns: 1fr; gap: 3rem; text-align: center; }
    .timeline::after { left: 25px; }
    .timeline-item { width: 100%; padding-left: 70px; padding-right: 15px; text-align: left !important; }
    .timeline-item:nth-child(even) { left: 0; }
    .timeline-icon { left: 0; }
}

/* Accessibility Focus */
:focus-visible {
    outline: 3px solid var(--primary-accent);
    outline-offset: 3px;
    border-radius: 4px;
}