/* ==============================================
TABLE OF CONTENTS
==============================================
1.  Root Variables & Global Styles
2.  Container & Helper Classes
3.  Header & Navigation
4.  Hero Section
5.  Section Styles
6.  Portfolio Section & Cards
7.  Skills Section
8.  Experience Section & Timeline
9.  Contact Section
10. Footer
11. Animations
12. Responsive Design
==============================================
*/

/* 1. Root Variables & Global Styles */
:root {
    --bg-dark: #0d1117;
    --bg-light: #161b22;
    --border-color: #30363d;
    --text-primary: #c9d1d9;
    --text-secondary: #8b949e;
    --accent-primary: #58a6ff;
    --accent-hover: #79c0ff;
    --font-primary: 'Inter', sans-serif;
    --font-secondary: 'Poppins', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: var(--font-primary);
    line-height: 1.6;
}

/* 2. Container & Helper Classes */
.container {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1rem;
}

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

/* 3. Header & Navigation */
#header {
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
    background: rgba(13, 17, 23, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
}

#header nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 4.5rem;
}

.logo {
    font-family: var(--font-secondary);
    font-weight: 700;
    font-size: 1.75rem;
    color: var(--accent-primary);
    text-decoration: none;
}

.nav-links {
    display: none; /* Hidden by default, shown on larger screens */
}

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    transition: color 0.3s ease;
}

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

.cta-button {
    background-color: var(--accent-primary);
    color: var(--bg-dark) !important;
    font-weight: 600;
    border-radius: 9999px;
    padding: 0.6rem 1.2rem !important;
    transition: background-color 0.3s ease;
}

.cta-button:hover {
    background-color: var(--accent-hover);
    color: var(--bg-dark) !important;
}

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

.mobile-menu-hidden {
    display: none;
    background-color: var(--bg-light);
    border-top: 1px solid var(--border-color);
}

.mobile-menu-hidden a {
    display: block;
    color: var(--text-primary);
    text-decoration: none;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.3s ease;
}

.mobile-menu-hidden a:hover {
    background-color: #30363d;
}

/* 4. Hero Section */
#hero {
    min-height: calc(100vh - 4.5rem);
    display: flex;
    align-items: center;
    padding: 4rem 1rem;
}

.hero-content {
    max-width: 700px;
}

.hero-title {
    font-family: var(--font-secondary);
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 700;
    color: #fff;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    color: var(--accent-primary);
    font-weight: 600;
    margin: 1rem 0;
}

.hero-text {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin-bottom: 2rem;
}

.social-links a {
    color: var(--text-secondary);
    font-size: 1.75rem;
    margin-right: 1.5rem;
    transition: color 0.3s ease;
}

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

/* 5. Section Styles */
section {
    padding: 6rem 0;
    border-bottom: 1px solid var(--border-color);
}

section:last-of-type {
    border-bottom: none;
}

.section-heading {
    font-family: var(--font-secondary);
    font-size: 2.5rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
}

.section-heading::after {
    content: '';
    position: absolute;
    width: 70%;
    height: 4px;
    background: var(--accent-primary);
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
}

/* 6. Portfolio Section & Cards */
.portfolio-grid {
    display: grid;
    gap: 2rem;
    grid-template-columns: 1fr;
}

.card {
    background-color: var(--bg-light);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    text-align: left;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-primary);
}

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

.card-icon {
    color: var(--accent-primary);
    font-size: 2rem;
    margin-right: 1rem;
}

.card-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #fff;
}

.card-body {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.card-list {
    list-style-position: inside;
    color: var(--text-secondary);
    padding-left: 0.5rem;
}

.card-list li {
    margin-bottom: 0.5rem;
}

.card-list li::marker {
    color: var(--accent-primary);
}

/* 7. Skills Section */
#skills {
    background-color: var(--bg-light);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.skill-category {
    background: var(--bg-dark);
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.skill-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--accent-primary);
    margin-bottom: 0.75rem;
}

/* 8. Experience Section & Timeline */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 2rem auto;
    padding: 2rem 0;
}

.timeline::before {
    content: '';
    position: absolute;
    width: 2px;
    background-color: var(--border-color);
    top: 0;
    bottom: 0;
    left: 1.25rem;
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    padding-left: 4rem;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: 0.7rem;
    top: 0.3rem;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--accent-primary);
    border: 3px solid var(--bg-dark);
    z-index: 1;
}

.timeline-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent-primary);
}

.timeline-subtitle {
    font-weight: 600;
    margin: 0.25rem 0;
}

.timeline-date {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.timeline-text {
    color: var(--text-secondary);
}


/* 9. Contact Section */
#contact {
    background-color: var(--bg-light);
}

.contact-text {
    max-width: 600px;
    margin: 0 auto 2rem auto;
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.contact-button {
    display: inline-block;
    background-color: var(--accent-primary);
    color: var(--bg-dark);
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: 8px;
    transition: transform 0.3s ease, background-color 0.3s ease;
}

.contact-button:hover {
    background-color: var(--accent-hover);
    transform: translateY(-3px);
}

/* 10. Footer */
footer {
    padding: 2rem 0;
    background-color: var(--bg-dark);
}

footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}


/* 11. Animations */
.scroll-animate {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.scroll-animate.visible {
    opacity: 1;
    transform: translateY(0);
}


/* 12. Responsive Design */
@media (min-width: 768px) {
    .nav-links {
        display: flex;
        align-items: center;
        gap: 0.5rem;
    }

    .mobile-menu-toggle {
        display: none;
    }

    .portfolio-grid {
        grid-template-columns: 1fr;
    }

    .timeline::before {
        left: 50%;
        transform: translateX(-50%);
    }

    .timeline-item {
        width: 50%;
        padding-left: 0;
        padding-right: 4rem;
        text-align: right;
    }

    .timeline-item:nth-child(even) {
        margin-left: 50%;
        padding-left: 4rem;
        padding-right: 0;
        text-align: left;
    }
    
    /* --- TIMELINE BULLET FIX --- */
    /* This corrects the bullet positioning for the desktop timeline */
    
    /* Position bullet for ODD items (on the left side) */
    .timeline-item:nth-child(odd)::before {
        left: 100%;
        transform: translateX(-50%);
    }

    /* Position bullet for EVEN items (on the right side) */
    .timeline-item:nth-child(even)::before {
        left: 0;
        transform: translateX(-50%);
    }
}