:root {
    --primary: #27ae60;
    --dark: #2c3e50;
    --light: #f4f7f6;
    --gold: #f1c40f;
}

/* --- GLOBAL STYLES --- */
html { scroll-behavior: smooth; }
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Segoe UI', sans-serif; line-height: 1.6; color: #333; overflow-x: hidden; }
.container { max-width: 1200px; margin: 0 auto; padding: 80px 20px; text-align: center; }
.bg-light { background: var(--light); width: 100%; }

/* --- NAVIGATION --- */
nav {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0 10%; background: #fff; position: sticky; top: 0; z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1); height: 80px;
}
.logo-wrapper a { text-decoration: none; display: flex; align-items: center; }
.site-logo { height: 50px; width: auto; transition: 0.3s; }
.site-logo:hover { transform: scale(1.08); filter: brightness(1.1); }

.nav-menu { display: flex; list-style: none; gap: 30px; }
.nav-menu a { text-decoration: none; color: var(--dark); font-weight: 500; position: relative; transition: 0.3s; }
.nav-menu a:hover { color: var(--primary); }
.nav-menu a::after { content: ''; position: absolute; width: 0; height: 2px; bottom: -5px; left: 0; background: var(--primary); transition: 0.3s; }
.nav-menu a:hover::after { width: 100%; }
.menu-toggle { display: none; font-size: 1.5rem; cursor: pointer; }

/* --- HEADER & STATUS BADGE --- */
header { background: var(--dark); color: white; padding: 100px 20px; text-align: center; }
.header-content { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; align-items: center; }

.status-badge {
    background: rgba(255, 255, 255, 0.1);
    padding: 8px 16px; border-radius: 20px;
    font-size: 0.85rem; margin-bottom: 15px;
    border: 1px solid rgba(255,255,255,0.2);
    display: flex; align-items: center; gap: 10px;
}
.pulse {
    width: 10px; height: 10px; background: var(--primary);
    border-radius: 50%; display: inline-block;
    animation: pulse-animation 2s infinite;
}
@keyframes pulse-animation {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(39, 174, 96, 0.7); }
    70% { transform: scale(1); box-shadow: 0 0 0 10px rgba(39, 174, 96, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(39, 174, 96, 0); }
}

.socials { display: flex; gap: 20px; margin: 25px 0; }
.socials a { color: white; font-size: 1.5rem; transition: 0.3s; }
.socials a:hover { color: var(--primary); transform: translateY(-3px); }
.blur-text { filter: blur(4px); transition: 0.3s; cursor: pointer; }
.blur-text:hover { filter: blur(0); }
.download-btn { background: var(--primary); color: white; padding: 12px 30px; border-radius: 5px; text-decoration: none; font-weight: bold; transition: 0.3s; }

/* --- RESEARCH STATUS CARD --- */
.status-card {
    background: white; padding: 40px; border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
    max-width: 700px; margin: 0 auto; text-align: left;
    border-left: 5px solid var(--primary);
}
.highlight { color: var(--primary); font-weight: bold; }
.progress-bar-container {
    background: #eee; border-radius: 10px; height: 25px;
    margin: 20px 0 10px; overflow: hidden;
}
.progress-bar {
    background: var(--primary); height: 100%; color: white;
    font-size: 0.8rem; display: flex; align-items: center;
    justify-content: center; font-weight: bold;
}

/* --- CARDS & TIMELINE --- */
.skills-grid, .research-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 25px; margin-top: 40px; }
.res-card, .work-card, .skill-category { 
    background: white; padding: 30px; border-radius: 12px; 
    box-shadow: 0 4px 15px rgba(0,0,0,0.05); text-align: left;
    transition: 0.3s;
}
.res-card:hover, .work-card:hover { transform: translateY(-10px); box-shadow: 0 12px 30px rgba(0,0,0,0.1); }
.tag { background: var(--primary); color: white; padding: 2px 8px; border-radius: 4px; font-size: 0.7rem; display: inline-block; margin-bottom: 10px; }

.skill-category ul { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.skill-category li { background: var(--light); border: 1px solid #ddd; padding: 4px 12px; border-radius: 20px; font-size: 0.9rem; transition: 0.3s; }
.skill-category li:hover { background: var(--primary); color: white; }

.timeline { max-width: 800px; margin: 0 auto; text-align: left; }
.timeline-item { border-left: 3px solid var(--primary); padding: 0 0 30px 30px; position: relative; }
@keyframes fadeInUp { from { opacity: 0; transform: translateX(-30px); } to { opacity: 1; transform: translateX(0); } }
.edu-fade { opacity: 0; animation: fadeInUp 0.8s ease forwards; }

/* --- BACK TO TOP --- */
#backToTop {
    display: none; position: fixed; bottom: 30px; right: 30px; z-index: 1001;
    background: var(--primary); color: white; border: none; padding: 15px;
    border-radius: 50%; cursor: pointer; transition: 0.3s;
}

/* --- MOBILE --- */
@media screen and (max-width: 768px) {
    nav { padding: 0 5%; }
    .menu-toggle { display: block; }
    .nav-menu {
        display: none; flex-direction: column; position: absolute; top: 80px;
        left: 0; width: 100%; background: white; padding: 20px;
        box-shadow: 0 5px 10px rgba(0,0,0,0.1);
    }
    .nav-menu.active { display: flex !important; }
}