/* ===== CSS Variables ===== */
:root {
    --bg-primary: #f8f9fa;
    --bg-secondary: #ffffff;
    --text-primary: #1e1e2a;
    --text-secondary: #4a4a5a;
    --accent: #6c63ff;
    --accent-hover: #5a52d5;
    --border-color: #e0e0e0;
    --card-bg: #ffffff;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
}

[data-theme="dark"] {
    --bg-primary: #12121a;
    --bg-secondary: #1a1a2e;
    --text-primary: #f0f0f5;
    --text-secondary: #b0b0c0;
    --border-color: #2a2a3e;
    --card-bg: #1e1e32;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

h2 {
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
    position: relative;
}

h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--accent);
    margin: 0.5rem auto 0;
    border-radius: 2px;
}

/* ===== Navigation ===== */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    z-index: 1000;
    transition: background 0.3s, border-color 0.3s;
}

nav {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: color 0.2s;
}

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

#theme-toggle {
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: color 0.2s;
}

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

/* ===== Hero Section ===== */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 1.5rem 4rem;
    max-width: 1100px;
    margin: 0 auto;
    gap: 4rem;
}

.hero-content {
    flex: 1;
}

.hero-subtitle {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 0.5rem;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1rem;
}

.hero-tagline {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
}

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

.btn {
    padding: 0.75rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    display: inline-block;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(108, 99, 255, 0.3);
}

.btn-secondary {
    border: 2px solid var(--border-color);
    color: var(--text-primary);
}

.btn-secondary:hover {
    border-color: var(--accent);
    background: var(--accent);
    color: #fff;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.hero-image img {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--accent);
    box-shadow: 0 20px 60px rgba(108, 99, 255, 0.15);
}

/* ===== About Section ===== */
#about {
    padding: 4rem 1.5rem;
    background: var(--bg-secondary);
    transition: background 0.3s;
}

.about-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: start;
}

.about-text p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.skills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin-top: 1.5rem;
}

.skill-tag {
    background: var(--bg-primary);
    padding: 0.4rem 1rem;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.skill-tag:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

.stat {
    background: var(--bg-primary);
    padding: 1.5rem;
    border-radius: 12px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.stat:hover {
    border-color: var(--accent);
    transform: translateY(-3px);
}

.stat-number {
    display: block;
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== Projects Section ===== */
#projects {
    padding: 4rem 1.5rem;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--card-bg);
    border-radius: 16px;
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.project-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    border-color: var(--accent);
}

.project-card img {
    width: 100%;
    height: 180px;
    object-fit: cover;
}

.project-info {
    padding: 1.5rem;
}

.project-info h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.project-info p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 1rem;
}

.project-tech span {
    background: var(--bg-primary);
    padding: 0.2rem 0.8rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.project-links {
    display: flex;
    gap: 1rem;
}

.project-links a {
    text-decoration: none;
    color: var(--accent);
    font-weight: 500;
    font-size: 0.9rem;
    transition: color 0.2s;
}

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

.project-links a i {
    margin-right: 0.3rem;
}

/* ===== Contact Section ===== */
#contact {
    padding: 4rem 1.5rem;
    text-align: center;
    background: var(--bg-secondary);
    transition: background 0.3s;
}

#contact p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    padding: 0.6rem 1.2rem;
    border-radius: 50px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.contact-item:hover {
    border-color: var(--accent);
    background: var(--accent);
    color: #fff;
}

.contact-item i {
    font-size: 1.2rem;
}

.copyright {
    margin-top: 3rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
    padding-top: 1.5rem;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .nav-links {
        gap: 1rem;
    }

    #hero {
        flex-direction: column-reverse;
        text-align: center;
        gap: 2rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .hero-tagline {
        margin: 0 auto 1.5rem;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-image img {
        width: 200px;
        height: 200px;
    }

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

    .contact-links {
        gap: 1rem;
    }
}

/* ===== Three Pillars ===== */
.pillars-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 1.5rem;
}

.pillar-card {
    background: var(--card-bg);
    padding: 2rem 1.5rem;
    border-radius: 16px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.pillar-card:hover {
    transform: translateY(-6px);
    border-color: var(--accent);
    box-shadow: var(--shadow);
}

.pillar-icon {
    font-size: 2.5rem;
    color: var(--accent);
    margin-bottom: 1rem;
}

.pillar-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.8rem;
}

.pillar-card p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.pillar-skills {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5rem;
}

.pillar-skills span {
    background: var(--bg-primary);
    padding: 0.2rem 0.8rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

/* ===== Project Categories ===== */
.project-category {
    margin-bottom: 3rem;
}

.project-category h3 {
    font-size: 1.6rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

/* ===== Hero Enhancements ===== */
.hero-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 550px;
}

.highlight {
    color: var(--accent);
    font-weight: 600;
}

/* ===== Skills (Logo Style) ===== */
#skills {
    padding: 4rem 1.5rem;
    background: var(--bg-secondary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
    margin-top: 1.5rem;
}

.skill-group {
    background: var(--card-bg);
    padding: 1.5rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

.skill-group:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow);
}

.skill-group h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.skill-logos {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
}

.skill-logo-item {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--bg-primary);
    padding: 0.3rem 0.8rem 0.3rem 0.5rem;
    border-radius: 50px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.skill-logo-item:hover {
    border-color: var(--accent);
    transform: translateY(-2px);
}

.skill-logo-item img {
    width: 20px;
    height: 20px;
    object-fit: contain;
}

.skill-logo-item span {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
}