:root {
    /* Dark mode (default) */
    --bg-body: #0e1622;
    --bg-container: #18222f;
    --bg-card: #1d2a3b;
    --bg-chip: #1f3145;
    --bg-hover: #2a405a;
    --bg-tab-active: #1d2a3b;
    --bg-tab-track: #141d29;

    --text-primary: #edf2f9;
    --text-secondary: #d5e2f2;
    --text-muted: #aac5f0;
    --text-dark: #0e1622;

    --border-color: #2a3748;
    --border-light: #33475e;

    /* Blue — filled buttons use --accent, text uses --accent-text */
    --accent: #6ea8fe;
    --accent-hover: #8bbaff;
    --accent-glow: rgba(110, 168, 254, 0.35);
    --accent-text: #8bbaff;           /* BRIGHT blue on dark bg */

    /* Coral — filled elements use --accent-complement */
    --accent-complement: #ff8a6f;
    --accent-complement-hover: #ffa38c;
    --accent-complement-glow: rgba(255, 138, 111, 0.3);
    --accent-complement-text: #ffb8a3; /* BRIGHT coral on dark bg */

    --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-container: 0 20px 40px -12px rgba(0, 0, 0, 0.7);

    --transition: all 0.3s ease;
}

[data-theme="light"] {
    --bg-body: #f0f4f9;
    --bg-container: #ffffff;
    --bg-card: #f8faff;
    --bg-chip: #e8edf5;
    --bg-hover: #dce4f0;
    --bg-tab-active: #ffffff;
    --bg-tab-track: #e6edf6;

    --text-primary: #1a2a3a;
    --text-secondary: #2c4056;
    --text-muted: #3a5a7a;
    --text-dark: #0e1622;

    --border-color: #d0dce8;
    --border-light: #b8c8d8;

    /* MUCH darker than dark mode — this is the visible toggle */
    --accent: #1f6fd0;
    --accent-hover: #185bb0;
    --accent-glow: rgba(31, 111, 208, 0.25);
    --accent-text: #0d3d7a;            /* DEEP navy on light bg */

    --accent-complement: #c94f34;
    --accent-complement-hover: #b3442c;
    --accent-complement-glow: rgba(201, 79, 52, 0.2);
    --accent-complement-text: #8a2a15; /* DEEP brick on light bg */

    --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-container: 0 20px 40px -12px rgba(0, 0, 0, 0.15);
}

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

body {
    background: var(--bg-body);
    font-family: 'Segoe UI', Roboto, system-ui, -apple-system, sans-serif;
    color: var(--text-primary);
    line-height: 1.6;
    padding: 2rem 1.5rem;
    display: flex;
    justify-content: center;
    transition: var(--transition);
}

.container {
    max-width: 1180px;
    width: 100%;
    background: var(--bg-container);
    border-radius: 32px;
    box-shadow: var(--shadow-container);
    padding: 2.5rem 2.8rem;
    border: 1px solid var(--border-color);
    animation: fadeInUp 0.9s ease-out;
    transition: var(--transition);
}

/* animations */
@keyframes fadeInUp { 0% { opacity: 0; transform: translateY(40px); } 100% { opacity: 1; transform: translateY(0); } }
@keyframes slideInLeft { 0% { opacity: 0; transform: translateX(-30px); } 100% { opacity: 1; transform: translateX(0); } }
@keyframes slideInRight { 0% { opacity: 0; transform: translateX(30px); } 100% { opacity: 1; transform: translateX(0); } }

.fade-up { animation: fadeInUp 0.8s ease-out both; }
.slide-left { animation: slideInLeft 0.8s ease-out both; }
.slide-right { animation: slideInRight 0.8s ease-out both; }
.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }

/* top bar */
.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2.5rem;
    padding-bottom: 1.4rem;
    border-bottom: 1px solid var(--border-color);
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.7rem;
    font-weight: 700;
    font-size: 1.05rem;
    letter-spacing: -0.02em;
}
.brand .dot {
    width: 10px; height: 10px; border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 12px var(--accent-glow);
    transition: var(--transition);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}
.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 0.92rem;
    font-weight: 500;
    transition: var(--transition);
}
.nav-links a:hover { color: var(--accent-text); }

.theme-toggle {
    background: var(--bg-chip);
    border: 1px solid var(--border-light);
    border-radius: 40px;
    padding: 0.4rem 1rem;
    cursor: pointer;
    color: var(--text-primary);
    font-size: 0.88rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: var(--transition);
}
.theme-toggle:hover { border-color: var(--accent); background: var(--bg-hover); }
.theme-toggle i { color: var(--accent-text); font-size: 0.95rem; transition: var(--transition); }

/* hero */
.hero {
    display: grid;
    grid-template-columns: 1.4fr 0.9fr;
    gap: 2.5rem;
    align-items: center;
    margin-bottom: 3rem;
}

.hero-eyebrow {
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--accent-complement-text);
    margin-bottom: 0.6rem;
    transition: var(--transition);
}

.hero h1 {
    font-size: clamp(2.2rem, 4vw, 3.1rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 0.8rem;
}
.hero h1 span { color: var(--accent-text); transition: var(--transition); }

.hero p {
    color: var(--text-secondary);
    font-size: 1.05rem;
    max-width: 52ch;
    margin-bottom: 1.4rem;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.7rem;
    margin-bottom: 1.2rem;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    background: var(--accent);
    color: var(--text-dark);
    padding: 0.6rem 1.4rem;
    border-radius: 40px;
    font-weight: 600;
    text-decoration: none;
    font-size: 0.92rem;
    transition: var(--transition);
    border: none;
}
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-2px); }

.btn-outline {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    background: transparent;
    color: var(--accent-text);
    padding: 0.55rem 1.35rem;
    border-radius: 40px;
    font-weight: 600;
    text-decoration: none;
    font-size: 0.92rem;
    border: 1.5px solid var(--accent);
    transition: var(--transition);
}
.btn-outline:hover { background: var(--accent); color: var(--text-dark); }

.hero-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 1rem;
    font-size: 0.86rem;
    color: var(--text-muted);
}
.hero-meta span { display: inline-flex; align-items: center; gap: 0.35rem; }
.hero-meta i { color: var(--accent-complement-text); transition: var(--transition); }

.hero-photo-wrap { display: flex; justify-content: center; }
.profile-photo {
    width: 210px;
    height: 210px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--accent);
    box-shadow: 0 0 35px var(--accent-glow);
    transition: var(--transition);
}
.profile-photo:hover { transform: scale(1.04); }

/* TABBED SHOWCASE*/
.showcase { margin-bottom: 3rem; }

.showcase-head {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    flex-wrap: wrap;
    gap: 0.8rem;
    margin-bottom: 1.2rem;
}
.showcase-head h2 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}
.showcase-head p { color: var(--text-muted); font-size: 0.92rem; max-width: 46ch; }

.tab-track {
    display: flex;
    gap: 0.25rem;
    background: var(--bg-tab-track);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 0.3rem;
    margin-bottom: 1.5rem;
    overflow-x: auto;
    scrollbar-width: none;
    transition: var(--transition);
}
.tab-track::-webkit-scrollbar { display: none; }

.tab-btn {
    flex: 1;
    min-width: max-content;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.45rem;
    background: transparent;
    border: none;
    border-radius: 12px;
    padding: 0.65rem 1.1rem;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    font-family: inherit;
}
.tab-btn i { font-size: 0.95rem; opacity: 0.8; }
.tab-btn:hover { color: var(--text-primary); }
.tab-btn.active {
    background: var(--bg-tab-active);
    color: var(--accent-text);
    box-shadow: var(--shadow-card);
}
.tab-btn.active i { color: var(--accent-text); opacity: 1; }

.tab-panel { display: none; animation: fadeInUp 0.35s ease-out both; }
.tab-panel.active { display: block; }

/* project cards */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.2rem;
}

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 1.4rem 1.5rem;
    display: flex;
    flex-direction: column;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.project-card::before {
    content: "";
    position: absolute;
    inset: 0 auto auto 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-complement));
    opacity: 0;
    transition: var(--transition);
}
.project-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent-complement);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.18);
}
.project-card:hover::before { opacity: 1; }

.project-icon {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: grid;
    place-items: center;
    font-size: 1.2rem;
    background: var(--bg-chip);
    color: var(--accent-complement-text);
    border: 1px solid var(--border-light);
    margin-bottom: 0.9rem;
    transition: var(--transition);
}
.project-card h3 {
    font-size: 1.05rem;
    font-weight: 650;
    margin-bottom: 0.3rem;
}
.project-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    flex: 1;
    margin-bottom: 0.9rem;
}
.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin-bottom: 1rem;
}
.project-tags span {
    font-size: 0.72rem;
    font-weight: 600;
    padding: 0.15rem 0.55rem;
    border-radius: 40px;
    background: var(--bg-chip);
    color: var(--text-muted);
    border: 1px solid var(--border-light);
}
.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.86rem;
    font-weight: 600;
    text-decoration: none;
    color: var(--accent-text);
    transition: var(--transition);
}
.project-link:hover { gap: 0.7rem; }
.project-link.muted { color: var(--text-muted); cursor: default; }

/* skills panel */
.skill-groups {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.2rem;
}
.skill-group {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 18px;
    padding: 1.2rem 1.3rem;
    transition: var(--transition);
}
.skill-group h3 {
    font-size: 0.82rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--accent-complement-text);
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    transition: var(--transition);
}
.skill-group h3 i { font-size: 0.85rem; }
.skill-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
}
.skill-chip {
    background: var(--bg-chip);
    border: 1px solid var(--border-light);
    border-radius: 40px;
    padding: 0.32rem 0.85rem;
    font-size: 0.83rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: var(--transition);
}
.skill-chip:hover {
    border-color: var(--accent-complement);
    background: var(--bg-hover);
    transform: translateY(-1px);
}

/* timeline */
.timeline {
    position: relative;
    padding-left: 1.4rem;
}
.timeline::before {
    content: "";
    position: absolute;
    left: 4px;
    top: 6px;
    bottom: 6px;
    width: 2px;
    background: var(--border-color);
    transition: var(--transition);
}

.timeline-item {
    position: relative;
    padding-bottom: 1.5rem;
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
    content: "";
    position: absolute;
    left: -1.4rem;
    top: 5px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent);
    border: 2px solid var(--bg-container);
    box-shadow: 0 0 0 2px var(--accent-glow);
    transition: var(--transition);
}

.timeline-head {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.3rem;
    margin-bottom: 0.2rem;
}
.timeline-head h3 {
    font-size: 1rem;
    font-weight: 650;
}
.timeline-head .org {
    color: var(--accent-complement-text);
    font-weight: 500;
    transition: var(--transition);
}
.timeline-date {
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
    background: var(--bg-chip);
    border: 1px solid var(--border-light);
    border-radius: 40px;
    padding: 0.15rem 0.7rem;
    white-space: nowrap;
}
.timeline-body {
    font-size: 0.9rem;
    color: var(--text-secondary);
}
.timeline-body ul {
    list-style: none;
    margin-top: 0.3rem;
}
.timeline-body li {
    display: flex;
    gap: 0.55rem;
    margin-bottom: 0.25rem;
}
.timeline-body li i {
    color: var(--accent-text);
    font-size: 0.6rem;
    margin-top: 0.45rem;
    transition: var(--transition);
}
.edu-modules {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
}
.edu-modules strong {
    color: var(--accent-complement-text);
    transition: var(--transition);
}

/* contact */
.contact-strip {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 2rem 2.2rem;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 1.2rem;
    margin-bottom: 2rem;
    transition: var(--transition);
}
.contact-strip h2 {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 0.2rem;
}
.contact-strip p {
    color: var(--text-muted);
    font-size: 0.95rem;
}
.contact-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.7rem;
}

/* footer */
.footer-note {
    border-top: 1px solid var(--border-color);
    padding-top: 1.2rem;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
    color: var(--text-muted);
    font-size: 0.84rem;
    transition: var(--transition);
}
.footer-note a {
    color: var(--accent-text);
    text-decoration: none;
    transition: var(--transition);
}
.footer-note a:hover { text-decoration: underline; }

/* responsive */
@media (max-width: 860px) {
    .container { padding: 1.8rem; }
    .hero { grid-template-columns: 1fr; gap: 1.8rem; }
    .hero-photo-wrap { order: -1; justify-content: flex-start; }
    .profile-photo { width: 150px; height: 150px; }
    .nav-links { display: none; }
    .showcase-head { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 520px) {
    .container { padding: 1.2rem; }
    body { padding: 1rem 0.75rem; }
    .hero h1 { font-size: 1.9rem; }
    .tab-btn { font-size: 0.82rem; padding: 0.55rem 0.8rem; }
    .tab-btn i { display: none; }
    .contact-strip { padding: 1.5rem; }
    .timeline-head { flex-direction: column; }
}