/* ----------------------------------
   CSS Variables & Base Design
---------------------------------- */
:root {
    /* Light Theme Colors */
    --primary: #3b82f6;      /* Blue 500 */
    --primary-op: rgba(59, 130, 246, 0.1);
    --secondary: #10b981;    /* Emerald 500 */
    --bg-color: #ffffff;
    --bg-alt: #f3f4f6;       /* Gray 100 */
    --text-main: #1f2937;    /* Gray 800 */
    --text-muted: #6b7280;   /* Gray 500 */
    --border-col: #e5e7eb;   /* Gray 200 */
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.2);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

[data-theme="dark"] {
    /* Dark Theme Colors */
    --primary: #60a5fa;      /* Blue 400 */
    --primary-op: rgba(96, 165, 250, 0.1);
    --secondary: #34d399;    /* Emerald 400 */
    --bg-color: #0f172a;     /* Slate 900 */
    --bg-alt: #1e293b;       /* Slate 800 */
    --text-main: #f8fafc;    /* Slate 50 */
    --text-muted: #94a3b8;   /* Slate 400 */
    --border-col: #334155;   /* Slate 700 */
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

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

html {
    scroll-behavior: smooth;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 800;
    line-height: 1.2;
}

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

ul {
    list-style: none;
}

/* ----------------------------------
   Layout Utilities
---------------------------------- */
.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

.py-section {
    padding: 100px 0;
}

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

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

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
    text-align: center;
    width: 100%;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--primary);
    border-radius: 2px;
}

.highlight {
    color: var(--primary);
}

/* ----------------------------------
   Loader
---------------------------------- */
.loader-container {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background-color: var(--bg-color);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}
.spinner {
    width: 50px; height: 50px;
    border: 5px solid var(--border-col);
    border-top: 5px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

/* ----------------------------------
   Buttons
---------------------------------- */
.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    border: none;
    font-size: 1rem;
}
.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.btn-primary {
    background-color: var(--primary);
    color: #fff;
}
.btn-secondary {
    background-color: transparent;
    color: var(--text-main);
    border: 2px solid var(--border-col);
}
.btn-secondary.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
}
.btn-outline-primary {
    background-color: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}
.btn-outline-primary:hover {
    background-color: var(--primary);
    color: #fff;
}
.nav-resume-btn {
    border: 2px solid var(--primary);
    padding: 0.4rem 1rem;
    border-radius: 6px;
    color: var(--primary);
    transition: all 0.2s ease;
}
.nav-resume-btn:hover {
    background-color: var(--primary);
    color: #fff;
}
.resume-text-link {
    color: var(--primary);
    font-weight: 600;
    text-decoration: underline;
    text-decoration-thickness: 2px;
    text-underline-offset: 4px;
    transition: color 0.2s ease;
}
.resume-text-link:hover {
    color: var(--secondary);
}

/* ----------------------------------
   Navigation
---------------------------------- */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    transition: background-color 0.3s ease, box-shadow 0.3s ease, padding 0.3s ease;
}
header.scrolled {
    background: var(--glass-bg);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--glass-border);
    box-shadow: var(--shadow-sm);
    padding: 10px 0;
}
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 5%;
}
.logo a {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: 1px;
}
.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}
.nav-links a {
    font-weight: 600;
    transition: color 0.2s ease;
}
.nav-links a:hover {
    color: var(--primary);
}
#theme-toggle {
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 1.2rem;
    cursor: pointer;
    transition: color 0.3s;
}

.burger { display: none; cursor: pointer; }
.burger div {
    width: 25px; height: 3px;
    background-color: var(--text-main);
    margin: 5px; transition: all 0.3s ease;
}

/* ----------------------------------
   Hero Section
---------------------------------- */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    padding-top: 80px;
}
.hero::before {
    content: '';
    position: absolute;
    top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle, var(--primary-op) 0%, transparent 40%);
    animation: pulsing 10s infinite;
    z-index: -1;
}
@keyframes pulsing {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}
.hero-title {
    font-size: 4rem;
    margin-bottom: 1rem;
}
.hero-subtitle {
    font-size: 1.5rem;
    color: var(--text-muted);
    font-weight: 400;
    margin-bottom: 2rem;
}
.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* ----------------------------------
   About Section
---------------------------------- */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    font-size: 1.1rem;
}
.social-links {
    margin-top: 2rem;
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}
.social-links a {
    font-size: 1.5rem;
    color: var(--text-main);
    transition: transform 0.2s, color 0.2s;
}
.social-links a:hover {
    color: var(--primary);
    transform: translateY(-3px);
}

/* ----------------------------------
   Skills Section
---------------------------------- */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 2rem;
}
.skill-card {
    background-color: var(--bg-color);
    padding: 2rem 1rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid var(--border-col);
}
.skill-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}
.skill-icon {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 1rem;
}
.skill-name {
    font-weight: 600;
}

/* ----------------------------------
   Projects Section
---------------------------------- */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
}
.project-card {
    background-color: var(--bg-alt);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: transform 0.3s;
    border: 1px solid var(--border-col);
    display: flex;
    flex-direction: column;
}
.project-card:hover {
    transform: translateY(-5px);
}
.project-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid var(--border-col);
}
.project-info {
    padding: 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}
.project-title {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}
.project-desc {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 1rem;
    flex: 1;
}
.tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}
.tech-badge {
    background-color: var(--primary-op);
    color: var(--primary);
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 600;
}
.project-links {
    display: flex;
    gap: 1rem;
}
.project-links a {
    color: var(--text-main);
    font-size: 1.2rem;
    transition: color 0.2s;
}
.project-links a:hover {
    color: var(--primary);
}

/* ----------------------------------
   Contact Section
---------------------------------- */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(15px);
    border: 1px solid var(--glass-border);
    padding: 3rem;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    max-width: 600px;
    margin: 0 auto;
}
.form-group {
    margin-bottom: 1.5rem;
}
.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
}
.form-group input, .form-group textarea {
    width: 100%;
    padding: 1rem;
    background-color: var(--bg-color);
    border: 1px solid var(--border-col);
    border-radius: 8px;
    color: var(--text-main);
    font-family: inherit;
    transition: border-color 0.2s, box-shadow 0.2s;
}
.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-op);
}
.btn-block {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}
.form-status {
    margin-top: 1rem;
    text-align: center;
    font-weight: 600;
}
.status-success { color: var(--secondary); }
.status-error { color: #ef4444; }

/* ----------------------------------
   Footer
---------------------------------- */
footer {
    background-color: var(--bg-color);
    padding: 2rem 0;
    border-top: 1px solid var(--border-col);
}

/* ----------------------------------
   Animations & Responsive
---------------------------------- */
.fade-in-section {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
    will-change: opacity, visibility;
}
.fade-in-section.is-visible {
    opacity: 1;
    transform: none;
}

/* Mobile Nav */
@media screen and (max-width: 768px) {
    .nav-links {
        position: fixed;
        right: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--glass-bg);
        backdrop-filter: blur(15px);
        width: 100%;
        height: calc(100vh - 70px);
        align-items: center;
        justify-content: center;
        transition: right 0.4s ease;
    }
    .nav-links.nav-active {
        right: 0;
    }
    .burger { display: block; }
    
    .hero-title { font-size: 2.5rem; }
    .hero-subtitle { font-size: 1.2rem; }
    .hero-buttons { flex-direction: column; }
}

/* Burger Animation */
.toggle .line1 { transform: rotate(-45deg) translate(-5px, 6px); }
.toggle .line2 { opacity: 0; }
.toggle .line3 { transform: rotate(45deg) translate(-5px, -6px); }