:root {
    /* Light Theme (Default) */
    --bg-color: #FFFFFF;
    --surface-color: #F8FAFC; /* Slate 50 */
    --surface-color-hover: #F1F5F9; /* Slate 100 */
    --text-primary: #0F172A; /* Slate 900 */
    --text-secondary: #475569; /* Slate 600 */
    --accent-color: #2563EB; /* Blue 600 */
    --accent-hover: #1D4ED8; /* Blue 700 */
    --border-color: #E2E8F0; /* Slate 200 */
    
    --font-family: 'Poppins', sans-serif;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    
    --container-width: 1200px;
    --radius: 12px;
}

html[data-theme="dark"] {
    /* Dark Theme */
    --bg-color: #0F172A; /* Slate 900 */
    --surface-color: #1E293B; /* Slate 800 */
    --surface-color-hover: #334155; /* Slate 700 */
    --text-primary: #F8FAFC; /* Slate 50 */
    --text-secondary: #94A3B8; /* Slate 400 */
    --accent-color: #60A5FA; /* Blue 400 */
    --accent-hover: #93C5FD; /* Blue 300 */
    --border-color: #334155; /* Slate 700 */
    
    --shadow-sm: none;
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.5);
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.7;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Header & Nav */
header {
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background-color 0.3s ease;
}

.navbar {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.logo img {
    height: 96px;
    width: auto;
    display: block;
}

.nav-links {
    display: flex;
    list-style: none;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

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

/* Theme Toggle Button */
#theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0.5rem;
    border-radius: 50%;
    color: var(--text-primary);
    transition: background-color 0.2s ease;
}

#theme-toggle:hover {
    background-color: var(--surface-color);
}

/* Hamburger */
.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    background-color: var(--text-primary);
    transition: all 0.3s ease-in-out;
}

/* Main Layout */
main {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 3rem 2rem;
}

.main-container {
    display: flex;
    gap: 3rem; /* Increased whitespace */
    align-items: flex-start;
}

.left-column {
    flex: 2; /* Gave tech/bike slightly more space */
}

.right-column {
    flex: 1;
    position: sticky;
    top: 6rem; /* Sticky sidebar effect */
}

/* Sections */
section {
    margin-bottom: 3rem;
    padding: 0; /* Minimalist: Remove box padding */
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

section.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Hero Section (About Me) */
.hero-section {
    text-align: left;
    margin-bottom: 4rem;
}

.hero-section h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    font-size: 1.25rem;
    font-style: italic;
    color: var(--accent-color);
    margin-bottom: 2rem;
    font-weight: 500;
}

.bio-content {
    max-width: 800px;
    margin-bottom: 2rem;
}

.bio-content p {
    margin-bottom: 1rem;
    font-size: 1.05rem;
}

.contact-info {
    display: flex;
    gap: 1rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.btn-contact {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background-color: var(--surface-color);
    color: var(--text-primary);
    padding: 0.75rem 1.25rem;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 500;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.btn-contact:hover {
    background-color: var(--surface-color-hover);
    border-color: var(--accent-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.credentials h3 {
    font-size: 1.1rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 1rem;
}

.skills-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.badge {
    background-color: var(--surface-color);
    color: var(--text-primary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    border: 1px solid var(--border-color);
    font-weight: 500;
}

/* Typography & Content */
h1, h2, h3 {
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

h2 {
    font-size: 1.75rem;
    font-weight: 600;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
    margin-bottom: 1.5rem;
}

p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

ul {
    padding-left: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

li {
    margin-bottom: 0.5rem;
}

/* Images */
img {
    width: 100%;
    height: auto;
    border-radius: var(--radius);
    transition: transform 0.3s ease;
}

img:hover {
    transform: scale(1.01);
}

/* Blog List specific */
#blog-list article {
    background-color: var(--surface-color);
    padding: 1.5rem;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    margin-bottom: 1.5rem !important; /* Override inline styles if needed */
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

#blog-list article:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-color);
}

#blog-list h3 {
    color: var(--text-primary) !important; /* Override inline style */
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

#blog-list a {
    text-decoration: none;
}

#blog-list p {
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

/* Buttons */
button {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    font-family: var(--font-family);
    transition: background-color 0.2s ease;
}

#back-to-blog {
    margin-bottom: 1.5rem;
}

button:hover {
    background-color: var(--accent-hover);
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 2rem;
    background-color: var(--bg-color);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 1024px) {
    .main-container {
        flex-direction: column;
    }
    
    .left-column, .right-column {
        width: 100%;
        position: static;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--bg-color);
        border-bottom: 1px solid var(--border-color);
        padding: 1rem 0;
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links li {
        margin: 0.5rem 0;
    }

    .hamburger {
        display: block;
    }
    
    .hamburger.active .bar:nth-child(2) { opacity: 0; }
    .hamburger.active .bar:nth-child(1) { transform: translateY(8px) rotate(45deg); }
    .hamburger.active .bar:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }
    
    h1 { font-size: 2rem; }
    .hero-section h1 { font-size: 2.25rem; }
}