/* 
====================================================================
    GLOBAL VARIABLES & RESETS
====================================================================
*/
:root {
    /* Dark Mode (Default) */
    --bg-body: #0f1115;
    --bg-card: #181b21;
    --bg-nav: rgba(15, 17, 21, 0.95);
    
    --text-main: #f0f2f5;
    --text-muted: #a0aec0;
    --text-accent: #64b5f6; /* Soft Blue */
    
    --primary-color: #3b82f6; /* Vibrant Blue */
    --primary-hover: #2563eb;
    
    --gradient-main: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    
    --border-color: #2d3748;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
    --shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.5);

    --transition-speed: 0.3s;
    --font-heading: 'Inter', system-ui, -apple-system, sans-serif;
    --font-body: 'Inter', system-ui, -apple-system, sans-serif;
}

body.light-mode {
    --bg-body: #ffffff;
    --bg-card: #f8fafc;
    --bg-nav: rgba(255, 255, 255, 0.95);

    --text-main: #1a202c;
    --text-muted: #64748b;
    --text-accent: #2563eb;

    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.15);
}

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

body {
    background-color: var(--bg-body);
    color: var(--text-main);
    font-family: var(--font-body);
    line-height: 1.6;
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

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

ul {
    list-style: none;
}

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

section {
    padding: 80px 20px;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
}

/* 
====================================================================
    TYPOGRAPHY
====================================================================
*/
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--text-main);
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 2rem;
    text-align: center;
}

.section-subtitle {
    display: block;
    text-align: center;
    color: var(--primary-color);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.875rem;
    margin-bottom: 0.5rem;
}

p {
    color: var(--text-muted);
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
}

/* 
====================================================================
    BUTTONS & COMPONENTS
====================================================================
*/
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    border: 2px solid transparent;
}

.btn-primary {
    background: var(--primary-color);
    color: #ffffff;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

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

.btn-outline:hover {
    background: rgba(59, 130, 246, 0.1);
    transform: translateY(-2px);
}

.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

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

/* 
====================================================================
    HEADER & NAVIGATION
====================================================================
*/
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--bg-nav);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.03em;
}

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

.nav-link {
    font-weight: 500;
    font-size: 0.95rem;
    color: var(--text-muted);
}

.nav-link:hover, .nav-link.active {
    color: var(--primary-color);
}

.theme-toggle {
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    background: var(--border-color);
}

.mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-main);
}

/* 
====================================================================
    HERO SECTION
====================================================================
*/
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 100px;
    background: radial-gradient(circle at 50% 50%, rgba(59, 130, 246, 0.15) 0%, transparent 50%);
}

.hero-content {
    max-width: 800px;
}

.hero-role {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 50px;
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary-color);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(59, 130, 246, 0.2);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.hero-title span {
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-desc {
    font-size: 1.25rem;
    max-width: 600px;
    margin: 0 auto 2.5rem;
}

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

/* 
====================================================================
    ABOUT & SKILLS SECTION
====================================================================
*/
.about-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
    align-items: center;
}

/* Skills Grid */
.skills-category {
    margin-bottom: 2rem;
}

.skills-category h4 {
    color: var(--text-augmented);
    border-left: 4px solid var(--primary-color);
    padding-left: 1rem;
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.skill-tag {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 0.75rem 1.25rem;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-main);
    transition: all 0.2s;
}

.skill-tag:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background: rgba(59, 130, 246, 0.05);
}

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

.project-card {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.project-content h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.project-tech {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: 1rem;
    font-size: 0.8rem;
    color: var(--primary-color);
}

.project-desc {
    flex-grow: 1;
    font-size: 1rem;
}

.project-link {
    margin-top: 1rem;
    display: inline-flex;
    align-items: center;
    color: var(--primary-color);
    font-weight: 600;
    gap: 0.5rem;
}

.project-link:hover {
    text-decoration: underline;
}

/* 
====================================================================
    EXPERIENCE & SERVICES
====================================================================
*/
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
    border-left: 2px solid var(--border-color);
    padding-left: 2rem;
}

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

.timeline-item::before {
    content: '';
    position: absolute;
    left: -2.6rem;
    top: 0.5rem;
    width: 1rem;
    height: 1rem;
    background: var(--primary-color);
    border-radius: 50%;
    border: 4px solid var(--bg-body);
}

.timeline-date {
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
    display: block;
}

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

.service-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    text-align: center;
    transition: all 0.3s ease;
}

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

.service-icon {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

/* 
====================================================================
    OBJECTIVE & CONTACT
====================================================================
*/
.objective-box {
    background: var(--bg-card);
    padding: 3rem;
    border-radius: 16px;
    text-align: center;
    border: 1px solid var(--border-color);
    max-width: 900px;
    margin: 0 auto;
}

.objective-box p {
    font-size: 1.25rem;
    color: var(--text-main);
    margin: 0;
}

.contact-container {
    max-width: 600px;
    margin: 0 auto;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-main);
    font-family: inherit;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 3rem;
}

.social-link {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 1.25rem;
    transition: all 0.3s ease;
}

.social-link:hover {
    color: var(--primary-color);
    border-color: var(--primary-color);
    transform: translateY(-3px);
}

/* 
====================================================================
    FOOTER
====================================================================
*/
footer {
    padding: 2rem 20px;
    text-align: center;
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

.footer-text {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.back-to-top {
    color: var(--primary-color);
    font-size: 0.9rem;
    margin-top: 0.5rem;
    display: inline-block;
}

/* 
====================================================================
    ANIMATIONS
====================================================================
*/
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 
====================================================================
    MEDIA QUERIES
====================================================================
*/
@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
    }
    
    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: var(--bg-nav);
        flex-direction: column;
        padding: 2rem;
        border-bottom: 1px solid var(--border-color);
        transform: translateY(-150%);
        transition: transform 0.3s ease;
    }
    
    .nav-links.active {
        transform: translateY(0);
    }
    
    .mobile-menu-btn {
        display: block;
    }

    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
    
    section {
        padding: 60px 20px;
    }
}