:root {
    /* Colors */
    --clr-bg: #0f172a;        /* Slate 900 */
    --clr-bg-alt: #1e293b;    /* Slate 800 */
    --clr-surface: #334155;   /* Slate 700 */
    --clr-primary: #3b82f6;   /* Blue 500 */
    --clr-primary-hover: #2563eb; /* Blue 600 */
    --clr-secondary: #10b981; /* Emerald 500 */
    --clr-text: #f8fafc;      /* Slate 50 */
    --clr-text-muted: #94a3b8;/* Slate 400 */
    --clr-border: #475569;    /* Slate 600 */
    --clr-whatsapp: #25D366;  /* WhatsApp Green */

    /* Typography */
    --font-main: 'Inter', sans-serif;
    
    /* Spacing */
    --section-py: 5rem;
    --container-px: 1.5rem;
    --border-radius: 0.75rem;

    /* Shadows & Transitions */
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.6), 0 10px 10px -5px rgba(0, 0, 0, 0.4);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

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

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

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Utilities */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--container-px);
}

.section {
    padding: var(--section-py) 0;
}

.bg-alt {
    background-color: var(--clr-bg-alt);
}

.text-center {
    text-align: center;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(to right, #fff, var(--clr-text-muted));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.section-desc {
    color: var(--clr-text-muted);
    font-size: 1.125rem;
    max-width: 600px;
    margin: 0 auto 3rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    border: none;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-primary {
    background-color: var(--clr-primary);
    color: #fff;
    box-shadow: 0 4px 14px 0 rgba(59, 130, 246, 0.39);
}

.btn-primary:hover {
    background-color: var(--clr-primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.3);
}

.btn-secondary {
    background-color: transparent;
    color: var(--clr-text);
    border: 1px solid var(--clr-border);
}

.btn-secondary:hover {
    border-color: var(--clr-text);
    background-color: rgba(255,255,255,0.05);
}

.btn-outline {
    background-color: transparent;
    color: var(--clr-primary);
    border: 1px solid var(--clr-primary);
}

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

.btn-whatsapp {
    background-color: var(--clr-whatsapp);
    color: #fff;
    font-weight: 600;
}

.btn-whatsapp:hover {
    background-color: #1FAF53;
    transform: translateY(-2px);
}

.btn-full {
    width: 100%;
}

/* Navbar */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(15, 23, 42, 0.85); /* Slate 900 with opacity */
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--clr-primary);
}

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

.nav-links a:not(.btn) {
    font-weight: 500;
    color: var(--clr-text-muted);
}

.nav-links a:not(.btn):hover {
    color: var(--clr-primary);
}

.mobile-menu-toggle {
    display: none;
    background: transparent;
    border: none;
    color: var(--clr-text);
    font-size: 1.5rem;
    cursor: pointer;
}

/* Hero */
.hero {
    position: relative;
    padding: 180px 0 100px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-content {
    position: relative;
    z-index: 10;
    max-width: 800px;
}

.badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    background-color: rgba(59, 130, 246, 0.1);
    color: var(--clr-primary);
    border-radius: 999px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(59, 130, 246, 0.2);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    letter-spacing: -1px;
}

.gradient-text {
    background: linear-gradient(135deg, var(--clr-primary), var(--clr-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--clr-text-muted);
    margin-bottom: 2.5rem;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.glow {
    position: absolute;
    width: 30vw;
    height: 30vw;
    background: var(--clr-primary);
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.15;
    z-index: 1;
}

.glow-1 {
    top: -10%;
    left: -10%;
}

.glow-2 {
    bottom: -10%;
    right: -10%;
    background: var(--clr-secondary);
}

/* Services */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background-color: var(--clr-bg-alt);
    padding: 2.5rem 2rem;
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.02);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--clr-primary), var(--clr-secondary));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s ease;
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(255, 255, 255, 0.1);
}

.service-card:hover::before {
    transform: scaleX(1);
}

.service-icon {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    display: inline-flex;
    padding: 1rem;
    border-radius: 1rem;
    background: rgba(255, 255, 255, 0.03);
}

.icon-python { color: #3b82f6; } /* Python / Blue */
.icon-powerbi { color: #f59e0b; } /* PowerBI / Yellow/Orange */
.icon-excel { color: #10b981; } /* Excel / Green */

.service-title {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.service-desc {
    color: var(--clr-text-muted);
    font-size: 0.95rem;
}

/* Portfolio */
.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.portfolio-card {
    background-color: var(--clr-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.portfolio-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.portfolio-img {
    position: relative;
    overflow: hidden;
    height: 220px;
}

.portfolio-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.portfolio-card:hover .portfolio-img img {
    transform: scale(1.05);
}

.portfolio-tags {
    position: absolute;
    top: 1rem;
    right: 1rem;
    display: flex;
    gap: 0.5rem;
}

.tag {
    background-color: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(4px);
    padding: 0.25rem 0.75rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 600;
    color: #fff;
}

.portfolio-content {
    padding: 1.5rem;
}

.portfolio-title {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.portfolio-desc {
    color: var(--clr-text-muted);
    font-size: 0.95rem;
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.items-center {
    align-items: center;
}

.about-image-wrapper {
    position: relative;
}

.about-image {
    border-radius: var(--border-radius);
    overflow: hidden;
    /* Soft border / glassmorphism effect around image */
    padding: 1rem;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.about-image img {
    border-radius: calc(var(--border-radius) - 0.5rem);
    width: 100%;
    aspect-ratio: 4/4;
    object-fit: cover;
}

.experience-badge {
    position: absolute;
    bottom: -1.5rem;
    right: -1.5rem;
    background: linear-gradient(135deg, var(--clr-primary), #6366f1);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid rgba(255,255,255,0.1);
}

.exp-number {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1;
}

.exp-text {
    font-size: 0.875rem;
    font-weight: 600;
    line-height: 1.2;
}

.about-text {
    color: var(--clr-text-muted);
    font-size: 1.05rem;
    margin-bottom: 1.5rem;
}

.skills-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-top: 2rem;
}

.skill-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.skill-item i {
    color: var(--clr-secondary);
    font-size: 1.25rem;
}

/* Contact Section */
.contact-wrapper {
    max-width: 600px;
    margin: 0 auto;
    background-color: var(--clr-bg);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.05);
    box-shadow: var(--shadow-md);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--clr-text);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    background-color: var(--clr-surface);
    border: 1px solid var(--clr-border);
    border-radius: 0.5rem;
    color: var(--clr-text);
    font-family: var(--font-main);
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--clr-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: 1.5rem 0;
    color: var(--clr-text-muted);
    font-size: 0.875rem;
}

.divider::before, .divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--clr-border);
}

.divider::not(:empty)::before { margin-right: 1em; }
.divider::not(:empty)::after { margin-left: 1em; }

/* Floating WhatsApp Button */
.floating-whatsapp {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background-color: var(--clr-whatsapp);
    color: white;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    z-index: 100;
    transition: transform 0.3s ease;
}

.floating-whatsapp:hover {
    transform: scale(1.1);
}

/* Footer */
.footer {
    padding: 2rem 0;
    background-color: var(--clr-bg);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

@media(min-width: 768px) {
    .footer-content {
        flex-direction: row;
        justify-content: space-between;
    }
}

.copyright {
    color: var(--clr-text-muted);
    font-size: 0.9rem;
    text-align: center;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    color: var(--clr-text-muted);
    font-size: 1.5rem;
}

.social-links a:hover {
    color: var(--clr-primary);
}

/* Animations */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.5, 0, 0, 1);
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Styles */
@media (max-width: 991px) {
    .hero-title {
        font-size: 2.75rem;
    }
    .about-grid {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    .experience-badge {
        right: 1rem;
        bottom: -1rem;
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background-color: var(--clr-bg);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 2rem;
        transition: 0.4s ease;
    }

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

    .mobile-menu-toggle {
        display: block;
    }
    
    .hero {
        padding-top: 140px;
    }
    
    .hero-title {
        font-size: 2.25rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }
    
    .hero-buttons .btn {
        width: 100%;
    }
    
    .skills-list {
        grid-template-columns: 1fr;
    }
}