/* ==========================================================================
   CSS Reset & Base
   ========================================================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* Light Mode Variables */
    --bg-main: #fcfcfc;
    --bg-surface: #ffffff;
    --bg-surface-hover: #f4f4f5;
    --text-main: #09090b;
    --text-muted: #52525b;
    --border-color: #e4e4e7;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary: #f4f4f5;
    --secondary-hover: #e4e4e7;
    --primary-text: #ffffff;
    --secondary-text: #09090b;
    
    --header-bg: rgba(252, 252, 252, 0.8);
    --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);
    --radius-md: 12px;
    --radius-lg: 24px;
    
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
}

[data-theme="dark"] {
    /* Dark Mode Variables */
    --bg-main: #09090b;
    --bg-surface: #18181b;
    --bg-surface-hover: #27272a;
    --text-main: #fafafa;
    --text-muted: #a1a1aa;
    --border-color: #27272a;
    --primary: #3b82f6;
    --primary-hover: #60a5fa;
    --secondary: #27272a;
    --secondary-hover: #3f3f46;
    --primary-text: #ffffff;
    --secondary-text: #fafafa;

    --header-bg: rgba(9, 9, 11, 0.8);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.6;
    font-size: 16px;
    transition: background-color var(--transition-normal), color var(--transition-normal);
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

/* ==========================================================================
   Typography
   ========================================================================== */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 0.5em;
    color: var(--text-main);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(2rem, 4vw, 2.5rem); letter-spacing: -0.01em; }
h3 { font-size: 1.25rem; }

p { margin-bottom: 1rem; color: var(--text-muted); }

/* ==========================================================================
   Layout & Utilities
   ========================================================================== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 6rem 0;
}

.section-header {
    margin-bottom: 4rem;
    text-align: left;
}

.section-subtitle {
    font-size: 1.125rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-weight: 500;
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
}

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

.btn-secondary:hover {
    background-color: var(--secondary-hover);
    transform: translateY(-2px);
}

.btn-block {
    width: 100%;
}

/* ==========================================================================
   Header & Nav
   ========================================================================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--header-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    transition: background-color var(--transition-normal);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-brand {
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.5px;
}

.nav-brand span {
    color: var(--primary);
}

.main-nav {
    display: flex;
}

.nav-list {
    display: flex;
    gap: 2rem;
}

.nav-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
}

.nav-link:hover {
    color: var(--text-main);
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.control-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    font-weight: 600;
    font-size: 0.875rem;
}

.control-btn:hover {
    background-color: var(--bg-surface-hover);
    color: var(--text-main);
}

.mobile-menu-btn {
    display: none;
    background: transparent;
    border: none;
    color: var(--text-main);
    cursor: pointer;
    padding: 0.5rem;
}

/* Theme Toggle Icons */
.sun-icon, .moon-icon { display: none; }
[data-theme="dark"] .sun-icon { display: block; }
[data-theme="light"] .moon-icon { display: block; }

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 70px;
}

.hero-content {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 4rem;
    align-items: center;
}

.hero-greeting {
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 1rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    font-size: 0.875rem;
}

.hero-title {
    margin-bottom: 1.5rem;
}

.hero-desc {
    font-size: 1.125rem;
    max-width: 540px;
    margin-bottom: 2.5rem;
}

.hero-actions {
    display: flex;
    gap: 1rem;
}

.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.tech-stack-circles {
    position: relative;
    width: 300px;
    height: 300px;
}

.circle {
    position: absolute;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
    font-weight: 700;
    color: var(--primary);
    font-size: 1.5rem;
    animation: float 6s ease-in-out infinite;
}

.circle-1 { width: 80px; height: 80px; top: 10%; left: 10%; animation-delay: 0s; }
.circle-2 { width: 120px; height: 120px; top: 35%; right: 5%; animation-delay: 2s; font-size: 2rem; }
.circle-3 { width: 100px; height: 100px; bottom: 10%; left: 20%; animation-delay: 4s; }

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
    100% { transform: translateY(0px); }
}

/* ==========================================================================
   Bento Grid & Components
   ========================================================================== */
.bento-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

/* Make first item span more if space allows */
@media (min-width: 768px) {
    .bento-grid .featured {
        grid-column: span 2;
    }
}

.project-card, .blog-card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 2rem;
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    height: 100%;
}

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

.project-category, .blog-category {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
    display: inline-block;
}

.project-title, .blog-title {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}

.project-desc, .blog-excerpt {
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.75rem;
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 9999px;
    color: var(--text-muted);
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-main);
}

.project-link:hover {
    color: var(--primary);
}

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

.skill-group {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 2rem;
}

.skill-group-title {
    font-size: 1.125rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
}

.skill-list li {
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skill-list li::before {
    content: "▹";
    color: var(--primary);
    font-size: 1.2rem;
}

.skill-name {
    color: var(--text-muted);
}

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

.about-lead {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--text-main);
    margin-bottom: 1.5rem;
}

.stats-grid {
    grid-template-columns: repeat(2, 1fr);
}

.stat-card {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.stat-card:nth-child(3) {
    grid-column: span 2;
}

.stat-num {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* ==========================================================================
   Blog Section
   ========================================================================== */
.blog-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.blog-meta {
    display: flex;
    justify-content: space-between;
    margin-bottom: 1rem;
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* ==========================================================================
   Contact Section
   ========================================================================== */
.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 4rem;
}

.social-links {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 2rem;
}

.social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--text-muted);
    font-weight: 500;
}

.social-link:hover {
    color: var(--primary);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    text-align: center;
}

.footer-inner {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.footer-note {
    font-size: 0.75rem;
}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 992px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-text {
        order: 2;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-visual {
        order: 1;
        margin-bottom: 2rem;
    }

    .about-grid, .contact-wrapper {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .contact-wrapper {
        padding: 2rem;
    }
}

@media (max-width: 768px) {
    h1 { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .main-nav {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        height: 0;
        overflow: hidden;
        background-color: var(--header-bg);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        transition: height var(--transition-normal);
        border-bottom: 1px solid var(--border-color);
    }
    
    .main-nav.is-open {
        height: calc(100vh - 70px);
    }
    
    .nav-list {
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        text-align: center;
    }
    
    .nav-link {
        font-size: 1.125rem;
    }
}

/* Animations added via JS class */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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