/* --- Root Variables (Professional Light Mode) --- */
:root {
    --bg-white: #ffffff;
    --bg-light: #f8fafc; /* Very subtle blue-grey */
    --text-dark: #0f172a; /* Slate 900 */
    --text-body: #334155; /* Slate 700 */
    --text-muted: #64748b; /* Slate 500 */
    --accent: #2563eb; /* Royal Blue */
    --accent-dark: #1d4ed8;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --font: 'Inter', sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    background-color: var(--bg-white);
    color: var(--text-body);
    font-family: var(--font);
    line-height: 1.6;
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }
a { text-decoration: none; transition: 0.3s; }
ul { list-style: none; }

/* --- Navbar --- */
.navbar {
    position: fixed; top: 0; width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
    padding: 16px 0;
}
.nav-content { display: flex; justify-content: space-between; align-items: center; }
.logo { font-weight: 800; font-size: 1.5rem; color: var(--text-dark); letter-spacing: -0.5px; }
.nav-links { display: flex; gap: 32px; align-items: center; }
.nav-links a { color: var(--text-body); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--accent); }
.hamburger { display: none; flex-direction: column; gap: 6px; background: none; border: none; cursor: pointer; }
.hamburger span { width: 25px; height: 3px; background: var(--text-dark); border-radius: 2px; transition: 0.3s; }
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(8px, 8px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(7px, -7px); }
.btn-nav {
    background: var(--accent); color: white !important;
    padding: 8px 20px; border-radius: 6px; font-weight: 600;
}
.btn-nav:hover { background: var(--accent-dark); }

/* --- Hero Section --- */
.hero { padding: 160px 0 100px; background: radial-gradient(circle at top right, #f1f5f9, #ffffff); }
.hero-grid { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 60px; align-items: center; }

.badge {
    background: #dbeafe; color: var(--accent);
    padding: 6px 12px; border-radius: 20px;
    font-size: 0.85rem; font-weight: 600; text-transform: uppercase;
    display: inline-block; margin-bottom: 20px; letter-spacing: 0.5px;
}
.hero h1 { font-size: 3.5rem; font-weight: 800; color: var(--text-dark); line-height: 1.1; margin-bottom: 15px; }
.text-gradient { color: var(--accent); }
.hero-subtitle { font-size: 1.25rem; font-weight: 600; color: var(--text-body); margin-bottom: 20px; }
.hero-desc { font-size: 1.1rem; color: var(--text-muted); margin-bottom: 40px; max-width: 550px; }

.hero-btns { display: flex; gap: 15px; }
.btn-primary {
    background: var(--accent); color: white;
    padding: 12px 28px; border-radius: 8px; font-weight: 600;
    border: 1px solid var(--accent);
}
.btn-primary:hover { background: white; border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }
.btn-outline {
    border: 1px solid var(--border); color: var(--text-dark);
    padding: 12px 28px; border-radius: 8px; font-weight: 600; background: white;
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }

/* Hero Image & Float Card */
.hero-image-wrapper { position: relative; }
.profile-img {
    width: 100%; max-width: 400px; border-radius: 24px;
    box-shadow: 20px 20px 60px rgba(0,0,0,0.1);
    border: 8px solid white;
}
.float-card {
    position: absolute; bottom: 30px; left: -20px;
    background: white; padding: 15px 25px; border-radius: 12px;
    box-shadow: var(--shadow); border: 1px solid var(--border);
    display: flex; align-items: center; gap: 15px;
}
.float-card i { font-size: 24px; color: var(--accent); }
.card-bold { display: block; font-weight: 700; color: var(--text-dark); font-size: 1.1rem; }
.card-small { font-size: 0.85rem; color: var(--text-muted); }

/* --- Section Styling --- */
.section { padding: 100px 0; }
.bg-light { background: var(--bg-light); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-title { font-size: 2rem; color: var(--text-dark); margin-bottom: 60px; font-weight: 700; }

/* About */
.lead-text { font-size: 1.3rem; color: var(--text-dark); margin-bottom: 20px; font-weight: 500; }
.about-text p {
    margin-bottom: 20px;
    font-size: 1.05rem;
    color: var(--text-body);
}
.divider {
    border: 0;
    height: 1px;
    background: var(--border);
    margin: 30px 0;
    width: 50%;
}
.about-text em {
    color: var(--accent);
    font-style: italic;
}

/* Timeline (Work Experience) */
.timeline { position: relative; max-width: 900px; }
.timeline::before {
    content: ''; position: absolute; left: 24px; top: 0; bottom: auto; height: calc(100% - 75px);
    width: 2px; background: var(--border);
}
.timeline-item { display: flex; gap: 30px; margin-bottom: 50px; position: relative; }
.timeline-icon {
    width: 50px; height: 50px; background: white;
    border: 1px solid var(--border); border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    z-index: 2; box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.timeline-icon img { width: 30px; height: 30px; object-fit: contain; }
.timeline-content { flex: 1; background: white; padding: 30px; border-radius: 12px; border: 1px solid var(--border); box-shadow: var(--shadow); }
.timeline-content:hover { border-color: var(--accent); }
.timeline-content h3 { font-size: 1.25rem; color: var(--text-dark); margin: 5px 0; }
.timeline-content .date { font-size: 0.85rem; font-weight: 600; color: var(--accent); text-transform: uppercase; }
.timeline-content .location { font-size: 0.9rem; color: var(--text-muted); margin-bottom: 15px; }
.timeline-content ul li { margin-bottom: 10px; padding-left: 20px; position: relative; }
.timeline-content ul li::before {
    content: '•'; color: var(--accent); font-weight: bold; 
    position: absolute; left: 0;
}

/* Projects Grid */
.grid-projects { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 30px; }
.card {
    background: white; padding: 30px; border-radius: 12px;
    border: 1px solid var(--border); transition: 0.3s;
}
.card:hover { transform: translateY(-5px); box-shadow: 0 10px 20px rgba(0,0,0,0.1); border-color: var(--accent); }
.card-header { display: flex; align-items: center; gap: 12px; margin-bottom: 15px; }
.card-icon { font-size: 1.2rem; color: var(--accent); background: #eff6ff; padding: 10px; border-radius: 8px; }
.card h3 { font-size: 1.1rem; color: var(--text-dark); }
.card p { font-size: 0.95rem; color: var(--text-muted); margin-bottom: 20px; }
.tags span {
    display: inline-block; background: var(--bg-light); color: var(--text-body);
    padding: 4px 10px; border-radius: 4px; font-size: 0.8rem;
    margin-right: 8px; border: 1px solid var(--border); font-weight: 500;
}

.highlight-award {
    color: #f59e0b;
    font-weight: 600;
    display: inline-block;
}

/* Skills */
.skills-wrapper { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; }
.skill-col h3 { font-size: 1.1rem; color: var(--text-dark); margin-bottom: 20px; display: flex; align-items: center; gap: 10px; }
.skill-col h3 i { color: var(--accent); }

/* Certifications & Awards */
.certifications-wrapper { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.certification-item { display: flex; gap: 20px; align-items: flex-start; }
.cert-badge {
    width: 60px; height: 60px; background: linear-gradient(135deg, #2563eb, #1d4ed8);
    border-radius: 12px; display: flex; align-items: center; justify-content: center;
    color: white; font-size: 28px; flex-shrink: 0;
}
.cert-content h3 { font-size: 1.1rem; color: var(--text-dark); margin-bottom: 8px; }
.cert-issuer { font-size: 0.9rem; color: var(--accent); font-weight: 600; margin-bottom: 4px; }
.cert-date { font-size: 0.85rem; color: var(--text-muted); }

/* Footer */
footer { background: #0f172a; color: white; padding: 80px 0 40px; text-align: center; }
footer h2 { font-size: 2.2rem; margin-bottom: 15px; }
footer p { color: #94a3b8; margin-bottom: 40px; }
.btn-footer { background: var(--accent); color: white; padding: 12px 25px; border-radius: 6px; font-weight: 600; }
.btn-footer-outline { border: 1px solid #334155; color: white; padding: 12px 25px; border-radius: 6px; font-weight: 600; }
.btn-footer-outline:hover { background: #1e293b; }
.copyright { margin-top: 60px; color: #475569; font-size: 0.9rem; }

/* Scroll Up Button */
#scrollTopBtn {
    display: none; position: fixed; bottom: 30px; right: 30px;
    z-index: 99; border: none; outline: none;
    background-color: var(--accent); color: white; cursor: pointer;
    padding: 15px; border-radius: 50%; font-size: 18px;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
    transition: 0.3s;
}
#scrollTopBtn:hover { background-color: var(--accent-dark); transform: translateY(-3px); }

/* Mobile Responsive */
@media (max-width: 900px) {
    .hamburger { display: flex; }
    .nav-links { 
        position: fixed; top: 80px; left: 0; right: 0;
        background: rgba(255, 255, 255, 0.98);
        flex-direction: column; gap: 16px;
        padding: 24px; border-bottom: 1px solid var(--border);
        transform: translateY(-100%); opacity: 0; transition: all 0.3s;
        pointer-events: none;
    }
    .nav-links.active { transform: translateY(0); opacity: 1; pointer-events: auto; }
    .hero-grid { grid-template-columns: 1fr; text-align: center; }
    .hero-image-wrapper { order: -1; margin-bottom: 30px; }
    .profile-img { max-width: 300px; margin: 0 auto; }
    .float-card { display: none; }
    .hero-btns { justify-content: center; }
    .timeline::before { left: 20px; }
    .timeline-item { gap: 15px; }
    .timeline-icon { min-width: 40px; width: 40px; height: 40px; }
    .timeline-icon img { width: 20px; height: 20px; }
    .skills-wrapper { grid-template-columns: 1fr; }
    .nav-links { flex-direction: column; gap: 16px; align-items: flex-start; }
}