:root {
    /* Colors */
    --bg-color: #0F172A;
    /* Dark Slate Blue tone */
    --bg-secondary: #1E293B;
    --text-primary: #F1F5F9;
    --text-secondary: #94A3B8;
    --accent-primary: #8B5CF6;
    /* Violet */
    --accent-secondary: #3B82F6;
    /* Blue */
    --accent-gradient: linear-gradient(135deg, #8B5CF6 0%, #3B82F6 100%);

    /* Spacing */
    --nav-width: 220px;
    --section-spacing: 120px;

    /* Config */
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

.summary {
    max-width: 720px;
    line-height: 1.7;
    font-size: 1rem;
    font-weight: 400;
    color: #cbd5e1;
    margin-bottom: 1.5rem;
}

.section-title {
    font-weight: 601;
    letter-spacing: 0.5px;
}


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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-color);
}

::-webkit-scrollbar-thumb {
    background: var(--bg-secondary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}

/* Layout */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    width: var(--nav-width);
    background: var(--bg-secondary);
    display: flex;
    flex-direction: column;
    justify-content: center;
    /* Center vertically */
    align-items: flex-start;
    /* Left align content */
    padding: 2rem;
    z-index: 1000;
    border-right: 1px solid rgba(255, 255, 255, 0.05);
}

.content {
    margin-left: var(--nav-width);
    padding: 0 4rem;
    max-width: 1200px;
}

/* Navigation */
.logo {
    display: none;
    /* User requested removal */
}

.nav-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    width: 100%;
}

.nav-links li {
    width: 100%;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 10px 15px;
    border-radius: 8px;
    width: 100%;
}

.nav-links a i {
    width: 20px;
    /* Fixed width for icon alignment */
    text-align: center;
    font-size: 1.1rem;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
    transform: translateX(5px);
}

.nav-links a.active {
    background: linear-gradient(90deg, rgba(139, 92, 246, 0.1) 0%, transparent 100%);
    color: var(--accent-primary);
    border-left: 3px solid var(--accent-primary);
}

/* Hide the old active line style */
.nav-links a.active::after {
    display: none;
}

.social-links-mini {
    margin-top: auto;
    /* Push to bottom */
    display: flex;
    flex-direction: row;
    /* Horizontal icons at bottom */
    gap: 1rem;
    padding-top: 2rem;
}

.social-links-mini a {
    color: var(--text-secondary);
    font-size: 1.2rem;
    transition: var(--transition);
}

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

/* Typography & Common elements */
h1,
h2,
h3 {
    color: var(--text-primary);
    font-weight: 700;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 60px;
    height: 4px;
    background: var(--accent-gradient);
    border-radius: 2px;
}

section {
    min-height: 80vh;
    /* Not full screen unless needed, but spacious */
    padding: 5rem 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 30px;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.4);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--accent-primary);
    color: var(--text-primary);
}

.btn-outline:hover {
    background: rgba(139, 92, 246, 0.1);
}

/* HERO Section */
#hero {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    min-height: 100vh;
}

.hero-text {
    flex: 1;
    padding-right: 2rem;
}

.hero-text .greeting {
    color: var(--accent-primary);
    font-size: 1.2rem;
    font-weight: 500;
    display: block;
    margin-bottom: 0.5rem;
}

.hero-text h1 {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 0.5rem;
}

.hero-text h2 {
    font-size: 1.5rem;
    color: var(--text-secondary);
    font-weight: 400;
    margin-bottom: 1.5rem;
}

.hero-text p {
    color: var(--text-secondary);
    max-width: 500px;
    margin-bottom: 2.5rem;
}

.cta-group {
    display: flex;
    gap: 1rem;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: flex-end;
}

.img-placeholder {
    width: 350px;
    height: 350px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 2px solid var(--accent-secondary);
    position: relative;
    overflow: hidden;
    /* Optional glow */
    box-shadow: 0 0 40px rgba(59, 130, 246, 0.2);
}

.img-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: 50% 40%;
}

/* ABOUT Section */
.summary {
    max-width: 800px;
    font-size: 1.1rem;
    color: var(--text-secondary);
}

/* WHAT I BRING Section */
.value-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.value-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.03);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    position: relative;
    overflow: hidden;
}

.value-card:hover {
    transform: translateY(-5px);
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.value-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--accent-gradient);
    opacity: 0;
    transition: var(--transition);
}

.value-card:hover::before {
    opacity: 1;
}

.icon-box {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    background: rgba(139, 92, 246, 0.1);
    width: 70px;
    height: 70px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-primary);
    transition: var(--transition);
}

.value-card:hover .icon-box {
    background: var(--accent-primary);
    color: white;
    transform: rotateY(180deg);
}

.value-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.value-card p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.6;
}

/* SKILLS Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.skill-category h3 {
    margin-bottom: 1.5rem;
    border-left: 3px solid var(--accent-primary);
    padding-left: 1rem;
}

.skill-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.skill-pills span {
    background: var(--bg-secondary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    transition: var(--transition);
    border: 1px solid transparent;
}

.skill-pills span:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-2px);
}

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

.project-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 2rem;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.03);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.project-card:hover {
    transform: translateY(-5px);
    border-color: rgba(139, 92, 246, 0.3);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.project-card h3 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-card p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

.btn-text {
    color: var(--accent-primary);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-text:hover {
    gap: 0.8rem;
    /* slight movement arrow */
}

/* CERTIFICATES & TEACHING */
.certificates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

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

.cert-placeholder {
    width: 100%;
    aspect-ratio: 4/3;
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
    overflow: hidden;
    /* Added to clip image corners */
}

.cert-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.cert-card:hover .cert-placeholder {
    transform: scale(1.03);
    border-color: var(--accent-secondary);
}

.teaching-card {
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    border-left: 4px solid var(--accent-primary);
}

.teaching-card h3 {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.badge {
    font-size: 0.8rem;
    background: rgba(139, 92, 246, 0.2);
    color: var(--accent-primary);
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
}

.teaching-highlights {
    list-style: none;
    margin-top: 1.5rem;
}

.teaching-highlights li {
    margin-bottom: 0.8rem;
    color: var(--text-secondary);
}

.teaching-highlights i {
    color: var(--accent-secondary);
    margin-right: 0.8rem;
}

/* CONTACT */
.contact-container {
    background: var(--bg-secondary);
    padding: 3rem;
    border-radius: var(--border-radius);
    max-width: 600px;
    margin: auto;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    color: var(--text-primary);
}

.contact-item i {
    color: var(--accent-primary);
    font-size: 1.4rem;
}

.contact-links {
    margin-top: 2rem;
    display: flex;
    gap: 1rem;
}

footer {
    padding: 2rem 0;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-top: 4rem;
}

/* RESPONSIVE */
@media (max-width: 900px) {
    .content {
        margin-left: 0;
        padding: 0 2rem;
    }

    .sidebar {
        width: 100%;
        height: auto;
        position: fixed;
        bottom: 0;
        top: auto;
        flex-direction: row;
        padding: 1rem 2rem;
        background: rgba(30, 41, 59, 0.95);
        backdrop-filter: blur(10px);
        border-right: none;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
    }

    .logo,
    .social-links-mini {
        display: none;
        /* Simplify mobile nav */
    }

    .nav-links {
        flex-direction: row;
        justify-content: space-around;
        width: 100%;
        gap: 0;
    }

    .nav-links a.active::after {
        display: none;
    }

    .nav-links a.active {
        color: var(--accent-primary);
        transform: translateY(-2px);
    }

    #hero {
        flex-direction: column-reverse;
        text-align: center;
        padding-top: 2rem;
    }

    .hero-text {
        padding-right: 0;
    }

    .hero-image {
        justify-content: center;
        margin-bottom: 2rem;
    }

    .cta-group {
        justify-content: center;
    }

    /* Adjust bottom spacing for mbile nav */
    main {
        padding-bottom: 80px;
    }
}