:root {
    --bg: #0e0e0e;
    --surface: #181818;
    --border: #2a2a2a;
    --text: #eee;
    --text-dim: #888;
    --accent: #fff;
}

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

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
}

h1, h2, h3 {
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    line-height: 1.3;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Header */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(17, 17, 17, 0.95);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
}

.site-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-weight: 800;
    font-size: 1rem;
    color: var(--text);
    letter-spacing: 0.5px;
}

.logo span { color: var(--accent); }

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

.nav-links a {
    color: var(--text-dim);
    font-size: 0.9rem;
    font-weight: 500;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text);
    text-decoration: none;
}

.btn-cv {
    padding: 0.5rem 1.2rem;
    background: var(--accent);
    color: #000;
    border-radius: 6px;
    font-weight: 700;
    font-size: 0.85rem;
}

.btn-cv:hover {
    text-decoration: none;
    opacity: 0.9;
}

/* Container */
.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Hero */
.hero {
    padding: 8rem 0 6rem;
}

.hero .badge {
    display: inline-block;
    padding: 0.3rem 1rem;
    border: 1px solid var(--accent);
    border-radius: 4px;
    font-size: 0.8rem;
    color: var(--accent);
    margin-bottom: 1.5rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
}

.hero h1 span { color: var(--accent); }

.hero .tagline {
    font-size: 1.1rem;
    color: var(--text-dim);
    max-width: 550px;
    margin-bottom: 2.5rem;
}

.hero-links {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 6px;
    font-weight: 700;
    font-size: 0.95rem;
}

.btn-primary {
    background: var(--accent);
    color: #000;
}

.btn-primary:hover { text-decoration: none; opacity: 0.9; }

.btn-outline {
    border: 1px solid var(--border);
    color: var(--text);
}

.btn-outline:hover { text-decoration: none; border-color: var(--text-dim); }

.social-links {
    display: flex;
    gap: 1.5rem;
}

.social-links a {
    color: var(--text-dim);
    font-size: 0.9rem;
}

.education-note {
    margin-top: 3rem;
    padding: 1.2rem 1.5rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--surface);
}

.education-note strong {
    color: var(--accent);
}

/* Page Header */
.page-header {
    padding: 8rem 0 3rem;
    border-bottom: 1px solid var(--border);
    margin-bottom: 4rem;
}

.page-header h1 {
    font-size: 2.8rem;
    margin-bottom: 0.8rem;
}

.page-header p {
    color: var(--text-dim);
    font-size: 1.1rem;
    max-width: 600px;
}

/* Section */
.section {
    padding: 4rem 0;
}

.section h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.section .section-desc {
    color: var(--text-dim);
    margin-bottom: 3rem;
    max-width: 600px;
}

/* Cards Grid */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.card {
    padding: 2rem;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--surface);
    transition: border-color 0.2s;
}

.card:hover {
    border-color: #444;
}

.card h3 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.card p {
    color: var(--text-dim);
    font-size: 0.95rem;
}

.card ul {
    list-style: none;
    margin-top: 0.5rem;
}

.card ul li {
    color: var(--text-dim);
    padding: 0.3rem 0;
    padding-left: 1.2rem;
    position: relative;
}

.card ul li::before {
    content: '-';
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* Project Cards */
.project-card {
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--surface);
    overflow: hidden;
    transition: border-color 0.2s;
}

.project-card:hover {
    border-color: #444;
}

.project-card .project-thumb {
    height: 160px;
    background: linear-gradient(135deg, #1a1a1a, #252525);
}

.project-card .project-body {
    padding: 1.5rem;
}

.project-card .tag {
    font-size: 0.75rem;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
}

.project-card h3 {
    margin: 0.5rem 0;
    font-size: 1.15rem;
}

.project-card p {
    color: var(--text-dim);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.project-card .links {
    display: flex;
    gap: 1.5rem;
}

.project-card .links a {
    font-size: 0.9rem;
    font-weight: 600;
}

/* Cert Cards */
.cert-card {
    display: block;
    padding: 1.5rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--surface);
    transition: border-color 0.2s;
}

.cert-card:hover {
    border-color: var(--accent);
    text-decoration: none;
}

.cert-card h3 {
    font-size: 1rem;
    margin-bottom: 0.4rem;
    color: var(--text);
}

.cert-card p {
    font-size: 0.85rem;
    color: var(--text-dim);
}

/* Volunteering */
.vol-card {
    padding: 2rem;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--surface);
}

.vol-card .role-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 0.8rem;
}

.vol-card h3 {
    font-size: 1.2rem;
}

.role-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.7rem;
    border: 1px solid var(--accent);
    color: var(--accent);
    border-radius: 4px;
    text-transform: uppercase;
    font-weight: 700;
}

.vol-card p {
    color: var(--text-dim);
}

/* Contact Page */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: start;
}

.contact-info h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.contact-info > p {
    color: var(--text-dim);
    margin-bottom: 2rem;
}

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

.contact-links a {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.7rem 1.2rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-dim);
    font-size: 0.9rem;
    width: fit-content;
    transition: border-color 0.2s, color 0.2s;
}

.contact-links a:hover {
    border-color: var(--accent);
    color: var(--accent);
    text-decoration: none;
}

/* Project Detail Page */
.project-detail {
    padding: 8rem 0 4rem;
}

.back-link {
    color: var(--text-dim);
    font-size: 0.9rem;
    margin-bottom: 2rem;
    display: inline-block;
}

.project-detail h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--accent);
}

.project-detail .subtitle {
    color: var(--text-dim);
    font-size: 1.1rem;
    margin-bottom: 3rem;
    max-width: 700px;
}

.detail-layout {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
}

.detail-section {
    margin-bottom: 3rem;
}

.detail-section h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text);
}

.detail-section p,
.detail-section li {
    color: var(--text-dim);
    margin-bottom: 0.8rem;
    line-height: 1.8;
}

.detail-section ul {
    list-style: none;
    padding: 0;
}

.detail-section ul li {
    padding-left: 1.2rem;
    position: relative;
}

.detail-section ul li::before {
    content: '-';
    position: absolute;
    left: 0;
    color: var(--accent);
}

.sidebar-box {
    padding: 1.5rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--surface);
    margin-bottom: 1.5rem;
}

.sidebar-box h3 {
    font-size: 1rem;
    margin-bottom: 0.8rem;
}

.sidebar-box ul {
    list-style: none;
}

.sidebar-box ul li {
    color: var(--text-dim);
    padding: 0.3rem 0;
    font-size: 0.9rem;
}

/* Footer */
.site-footer {
    padding: 3rem 0;
    text-align: center;
    border-top: 1px solid var(--border);
    color: var(--text-dim);
    font-size: 0.85rem;
    margin-top: 4rem;
}

/* Hamburger Menu */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.menu-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--text);
    margin: 5px 0;
    transition: transform 0.3s, opacity 0.3s;
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Responsive */
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }

    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg);
        border: 1px solid var(--border);
        border-top: none;
        padding: 1.5rem 2rem;
        gap: 0;
    }

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

    .nav-links li {
        list-style: none;
    }

    .nav-links a {
        display: block;
        padding: 0.8rem 0;
        border-bottom: 1px solid var(--border);
    }

    .nav-links li:last-child a {
        border-bottom: none;
    }

    .site-header .container {
        position: relative;
    }

    .hero h1 { font-size: 2.2rem; }
    .hero { padding: 5rem 0 3rem; }
    .hero .tagline { font-size: 1rem; }
    .hero-links { flex-direction: column; gap: 1rem; }
    .hero-links .btn { text-align: center; }

    .page-header { padding: 5rem 0 2rem; margin-bottom: 2rem; }
    .page-header h1 { font-size: 1.8rem; }

    .grid-2 { grid-template-columns: 1fr; }
    .grid-3 { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .detail-layout { grid-template-columns: 1fr; }

    .project-detail { padding: 5rem 0 3rem; }
    .project-detail h1 { font-size: 1.8rem; }

    .container { padding: 0 1.2rem; }
    .section { padding: 2.5rem 0; }

    .education-note { margin-top: 2rem; }
    .social-links { flex-wrap: wrap; }
}

@media (max-width: 480px) {
    .logo { font-size: 0.85rem; }
    .hero h1 { font-size: 1.8rem; }
    .btn { padding: 0.7rem 1.5rem; font-size: 0.9rem; }
    .card { padding: 1.5rem; }
    .vol-card { padding: 1.5rem; }
    .contact-info h2 { font-size: 1.5rem; }
}