:root {
    --bg: #07070d;
    --surface: rgba(255, 255, 255, 0.04);
    --border: rgba(255, 255, 255, 0.1);
    --text: #f3f3f6;
    --muted: #b4b4c3;
    --primary: #7c5cff;
    --primary-2: #22d3ee;
    --header-bg: rgba(7, 7, 13, 0.8);
    --shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
    --radius: 18px;
    color-scheme: dark;
}

.page.light {
    --bg: #f6f7fb;
    --surface: rgba(15, 23, 42, 0.04);
    --border: rgba(15, 23, 42, 0.1);
    --text: #0f172a;
    --muted: #46536b;
    --primary: #6d28d9;
    --primary-2: #0891b2;
    --header-bg: rgba(246, 247, 251, 0.8);
    --shadow: 0 20px 60px rgba(15, 23, 42, 0.1);
    color-scheme: light;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
    background: #07070d;
    color: var(--text);
    font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
}

button, input, select { font: inherit; }

.page {
    min-height: 100vh;
    background:
        radial-gradient(circle at top left, rgba(124, 92, 255, 0.15), transparent 40%),
        radial-gradient(circle at top right, rgba(34, 211, 238, 0.1), transparent 40%),
        var(--bg);
    color: var(--text);
}

.container { width: min(1100px, calc(100% - 32px)); margin-inline: auto; }

/* Scroll Progress */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--primary-2));
    z-index: 100;
    transition: width 0.1s linear;
    box-shadow: 0 0 10px var(--primary);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 40;
    backdrop-filter: blur(16px);
    background: var(--header-bg);
    border-bottom: 1px solid var(--border);
}

.nav {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 14px 0;
}

.brand { border: none; background: none; color: var(--text); font-weight: 800; letter-spacing: 0.02em; cursor: pointer; }
.nav-links { display: flex; align-items: center; gap: 8px; }
.nav-link { border: 1px solid transparent; background: none; color: var(--muted); padding: 9px 12px; border-radius: 999px; cursor: pointer; font-weight: 600; transition: all 0.2s; }
.nav-link:hover { color: var(--text); background: var(--surface); }
.nav-link.active { color: var(--text); background: var(--surface); border-color: var(--border); }

.nav-controls { display: flex; align-items: center; gap: 8px; }

.cmdk-trigger {
    padding: 8px 12px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--muted);
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
}
.cmdk-trigger:hover { color: var(--text); border-color: var(--primary); }

.icon-button {
    width: 40px; height: 40px;
    border-radius: 999px;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    cursor: pointer;
    display: grid;
    place-items: center;
    transition: all 0.2s;
}

.icon-button:hover, .button:hover, .page-card:hover, .contact-item:hover, .favorite-button:hover, .filter-button:hover, .modal-close:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
    box-shadow: 0 4px 12px rgba(124, 92, 255, 0.2);
}

.menu-toggle { display: none; }
.main { padding: 40px 0 80px; }

.app-page { display: none; }
.app-page.active { display: block; animation: fade-in 0.4s cubic-bezier(0.16, 1, 0.3, 1); }
.hidden { display: none !important; }

.page-header { margin-bottom: 24px; }
.page-header h2 { font-size: clamp(1.8rem, 3vw, 2.8rem); margin-bottom: 8px; }
.section-text { color: var(--muted); max-width: 760px; }

.panel {
    border: 1px solid var(--border);
    background: var(--surface);
    backdrop-filter: blur(10px);
    border-radius: 24px;
    padding: 32px;
    box-shadow: var(--shadow);
}

.home-hero { max-width: 900px; display: grid; gap: 16px; }

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px;
    border-radius: 999px;
    background: var(--surface);
    border: 1px solid var(--border);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--muted);
    width: fit-content;
}

.status-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    background: #10b981;
    box-shadow: 0 0 10px #10b981;
    animation: pulse 2s infinite;
}

h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); line-height: 1.05; letter-spacing: -0.02em; }
.subtitle { font-size: clamp(1.2rem, 2.5vw, 1.6rem); font-weight: 600; color: var(--primary-2); min-height: 2rem; }
.bio { max-width: 760px; color: var(--muted); font-size: 1.05rem; }
kbd { background: var(--surface); border: 1px solid var(--border); padding: 2px 6px; border-radius: 6px; font-size: 0.85em; font-family: monospace; }

.actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 12px; }

.button {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 12px 20px; border-radius: 999px;
    border: 1px solid var(--border); background: var(--surface);
    color: var(--text); text-decoration: none; font-weight: 700; cursor: pointer;
    transition: all 0.2s;
}
.button.primary { background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #06060a; border: none; box-shadow: 0 4px 15px rgba(124, 92, 255, 0.3); }
.button.small { padding: 9px 14px; font-size: 0.9rem; }
.button.outline { background: transparent; }

.home-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin-top: 40px; }

.page-card {
    text-align: left; padding: 24px; border-radius: 20px;
    border: 1px solid var(--border); background: var(--surface);
    color: var(--text); cursor: pointer; display: grid; gap: 8px;
    transition: all 0.3s; position: relative; overflow: hidden;
}
.page-card::before {
    content: ""; position: absolute; inset: 0; border-radius: inherit;
    background: radial-gradient(circle at 50% 50%, rgba(124, 92, 255, 0.15), transparent 60%);
    opacity: 0; transition: opacity 0.3s; z-index: 0; pointer-events: none;
}
.page-card:hover::before { opacity: 1; }
.page-card > * { position: relative; z-index: 1; }
.card-icon { font-size: 1.6rem; }
.page-card-title { font-weight: 800; font-size: 1.1rem; }
.page-card-body { color: var(--muted); font-size: 0.9rem; }

.accordion-list { display: grid; gap: 14px; }
.accordion { border: 1px solid var(--border); background: var(--surface); border-radius: 18px; overflow: hidden; transition: border-color 0.2s; }
.accordion:hover { border-color: var(--primary); }
.accordion-header { width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 14px; padding: 20px; background: none; border: none; color: var(--text); cursor: pointer; font-weight: 800; text-align: left; }
summary.accordion-header { list-style: none; }
summary.accordion-header::-webkit-details-marker { display: none; }
.chevron { color: var(--muted); transform: rotate(-90deg); transition: transform 0.3s; }
.accordion.open .chevron, details[open].accordion .chevron { transform: rotate(0deg); }
.accordion-body { display: grid; grid-template-rows: 0fr; transition: grid-template-rows 0.3s ease; }
.accordion.open .accordion-body, details[open].accordion .accordion-body { grid-template-rows: 1fr; }
.accordion-inner { overflow: hidden; }
.accordion-content { padding: 0 20px 20px; }

.chips { display: flex; flex-wrap: wrap; gap: 10px; }
.chip { padding: 10px 16px; border: 1px solid var(--border); background: var(--bg); border-radius: 999px; color: var(--text); font-weight: 600; font-size: 0.9rem; }

.toolbar { display: grid; gap: 14px; margin-bottom: 24px; }
.toolbar-row { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.search-input { flex: 1 1 340px; padding: 14px 16px; border-radius: 14px; border: 1px solid var(--border); background: var(--bg); color: var(--text); outline: none; }
.sort-select { min-width: 180px; padding: 14px 16px; border-radius: 14px; border: 1px solid var(--border); background: var(--bg); color: var(--text); outline: none; }
.search-input:focus-visible, .sort-select:focus-visible { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(124, 92, 255, 0.2); }

.filters { display: flex; flex-wrap: wrap; gap: 10px; }
.filter-button { padding: 9px 14px; border-radius: 999px; border: 1px solid var(--border); background: transparent; color: var(--muted); font-weight: 700; cursor: pointer; transition: all 0.2s; }
.filter-button:hover { color: var(--text); border-color: var(--primary); }
.filter-button.active { background: linear-gradient(135deg, var(--primary), var(--primary-2)); color: #06060a; border-color: transparent; }

.projects-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.card { border: 1px solid var(--border); background: var(--surface); border-radius: var(--radius); padding: 20px; transition: all 0.3s; position: relative; overflow: hidden; }
.card::before { content: ""; position: absolute; inset: 0; border-radius: inherit; background: radial-gradient(circle at 50% 50%, rgba(124, 92, 255, 0.15), transparent 60%); opacity: 0; transition: opacity 0.3s; z-index: 0; pointer-events: none; }
.card:hover::before { opacity: 1; }
.card > * { position: relative; z-index: 1; }
.card:hover { transform: translateY(-4px); border-color: var(--primary); box-shadow: 0 10px 30px rgba(0,0,0,0.2); }

.project-banner { position: relative; display: grid; place-items: center; height: 100px; border-radius: 14px; border: 1px solid var(--border); margin-bottom: 16px; overflow: hidden; }
.project-icon { font-size: 2.2rem; filter: drop-shadow(0 8px 18px rgba(0, 0, 0, 0.3)); }
.favorite-button { position: absolute; top: 10px; right: 10px; width: 36px; height: 36px; border-radius: 999px; border: 1px solid var(--border); background: var(--bg); color: var(--text); cursor: pointer; transition: all 0.2s; }
.favorite-button.active { color: #ff6b81; border-color: rgba(255, 107, 129, 0.5); background: rgba(255, 107, 129, 0.1); }

.badge { display: inline-flex; padding: 6px 12px; border-radius: 999px; font-size: 0.8rem; font-weight: 800; margin-bottom: 12px; }
.badge.prediction-models { background: rgba(34, 211, 238, 0.15); color: #22d3ee; border: 1px solid rgba(34, 211, 238, 0.3); }
.badge.transformers { background: rgba(124, 92, 255, 0.15); color: #a78bfa; border: 1px solid rgba(124, 92, 255, 0.3); }
.badge.fine-tuning { background: rgba(244, 114, 182, 0.15); color: #f472b6; border: 1px solid rgba(244, 114, 182, 0.3); }
.badge.graph-rag { background: rgba(52, 211, 153, 0.15); color: #34d399; border: 1px solid rgba(52, 211, 153, 0.3); }
.badge.multi-agent-system { background: rgba(255, 145, 77, 0.15); color: #ff914d; border: 1px solid rgba(255, 145, 77, 0.3); }
.badge.data-science { background: rgba(96, 165, 250, 0.15); color: #60a5fa; border: 1px solid rgba(96, 165, 250, 0.3); }

.project-banner.prediction-models { background: linear-gradient(135deg, rgba(34, 211, 238, 0.2), rgba(124, 92, 255, 0.1)); }
.project-banner.transformers { background: linear-gradient(135deg, rgba(124, 92, 255, 0.2), rgba(167, 139, 250, 0.1)); }
.project-banner.fine-tuning { background: linear-gradient(135deg, rgba(244, 114, 182, 0.2), rgba(124, 92, 255, 0.1)); }
.project-banner.graph-rag { background: linear-gradient(135deg, rgba(52, 211, 153, 0.2), rgba(34, 211, 238, 0.1)); }
.project-banner.multi-agent-system { background: linear-gradient(135deg, rgba(255, 145, 77, 0.2), rgba(124, 92, 255, 0.1)); }
.project-banner.data-science { background: linear-gradient(135deg, rgba(96, 165, 250, 0.2), rgba(34, 211, 238, 0.1)); }

.tech-chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0; }
.tech-chip { padding: 6px 10px; border-radius: 999px; border: 1px solid var(--border); background: var(--bg); color: var(--muted); font-size: 0.8rem; font-weight: 600; }
.card-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }

.modal-root { position: fixed; inset: 0; z-index: 60; display: grid; place-items: center; padding: 20px; animation: fade-in 0.2s; }
.modal-overlay { position: absolute; inset: 0; background: rgba(0, 0, 0, 0.7); backdrop-filter: blur(8px); }
.modal { position: relative; z-index: 1; width: min(700px, 100%); max-height: min(85vh, 900px); overflow: auto; padding: 32px; border-radius: 24px; border: 1px solid var(--border); background: var(--bg); box-shadow: var(--shadow); }
.modal-close { position: absolute; top: 16px; right: 16px; width: 40px; height: 40px; border-radius: 999px; border: 1px solid var(--border); background: var(--surface); color: var(--text); font-size: 1.4rem; line-height: 1; cursor: pointer; }
.modal-details { color: var(--muted); margin: 16px 0; }

.journey-summary { display: grid; gap: 4px; }
.journey-period { color: var(--primary-2); font-size: 0.85rem; font-weight: 800; text-transform: uppercase; letter-spacing: 0.05em; }
.journey-title { font-weight: 800; font-size: 1.1rem; }
.journey-description { color: var(--muted); margin-top: 8px; }

.testimonial-card { padding: 32px; border: 1px solid var(--border); background: var(--surface); border-radius: 24px; font-size: 1.1rem; font-style: italic; }
.testimonial-card p { margin-bottom: 20px; }
.testimonial-meta { display: grid; gap: 4px; color: var(--muted); font-style: normal; }
.testimonial-controls { display: flex; gap: 10px; margin-top: 20px; }
.testimonial-button { width: 44px; height: 44px; border-radius: 999px; border: 1px solid var(--border); background: var(--surface); color: var(--text); cursor: pointer; font-size: 1.2rem; }

.contact-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.contact-item { display: flex; align-items: center; gap: 14px; padding: 20px; border-radius: 18px; border: 1px solid var(--border); background: var(--bg); color: var(--text); text-decoration: none; transition: all 0.2s; }
.contact-item:hover { border-color: var(--primary); transform: translateY(-2px); }
.icon { font-size: 1.5rem; }
.contact-text { display: flex; flex-direction: column; gap: 2px; }
.contact-text small { color: var(--muted); }

.footer { border-top: 1px solid var(--border); margin-top: 60px; }
.footer-inner { display: flex; align-items: center; justify-content: center; padding: 24px 0; color: var(--muted); font-size: 0.9rem; }

/* Command Palette */
.cmdk-overlay { position: fixed; inset: 0; background: rgba(0, 0, 0, 0.6); backdrop-filter: blur(12px); z-index: 100; display: grid; place-items: center; animation: fade-in 0.2s ease; }
.cmdk-modal { width: min(600px, 90%); background: var(--bg); border: 1px solid var(--border); border-radius: 20px; padding: 20px; box-shadow: var(--shadow); }
.cmdk-input { width: 100%; padding: 16px; font-size: 1.2rem; background: transparent; border: none; color: var(--text); outline: none; border-bottom: 1px solid var(--border); margin-bottom: 12px; }
.cmdk-results { display: grid; gap: 8px; max-height: 300px; overflow-y: auto; }
.cmdk-item { display: flex; align-items: center; gap: 12px; padding: 12px 16px; border-radius: 12px; background: var(--surface); border: 1px solid transparent; color: var(--text); cursor: pointer; text-align: left; width: 100%; transition: all 0.2s; }
.cmdk-item:hover { border-color: var(--primary); background: rgba(124, 92, 255, 0.1); }
.cmdk-type { font-size: 0.7rem; font-weight: 800; padding: 4px 8px; border-radius: 6px; background: var(--primary); color: #fff; text-transform: uppercase; }
.cmdk-label { font-weight: 600; }

/* Toast */
.toast-container { position: fixed; bottom: 24px; right: 24px; z-index: 150; display: grid; gap: 10px; pointer-events: none; }
.toast { padding: 14px 20px; background: var(--bg); border: 1px solid var(--primary); border-radius: 14px; color: var(--text); font-weight: 600; box-shadow: var(--shadow); animation: slide-in 0.3s cubic-bezier(0.16, 1, 0.3, 1); pointer-events: auto; }

/* Typing Cursor */
.cursor { animation: blink 1s step-end infinite; color: var(--primary-2); font-weight: 800; }

:focus-visible { outline: 2px solid var(--primary-2); outline-offset: 2px; }

@keyframes fade-in { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
@keyframes blink { 50% { opacity: 0; } }
@keyframes slide-in { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes pulse { 0% { opacity: 1; transform: scale(1); } 50% { opacity: 0.6; transform: scale(1.2); } 100% { opacity: 1; transform: scale(1); } }

@media (max-width: 900px) {
    .home-grid, .projects-grid, .contact-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 760px) {
    .menu-toggle { display: inline-flex; }
    .nav-links { position: absolute; top: 100%; left: 0; right: 0; display: none; flex-direction: column; align-items: stretch; gap: 8px; padding: 14px 16px 18px; background: var(--header-bg); border-bottom: 1px solid var(--border); backdrop-filter: blur(16px); }
    .nav-links.open { display: flex; }
    .nav-link { width: 100%; text-align: left; }
    .home-grid, .projects-grid, .contact-grid { grid-template-columns: 1fr; }
    .toolbar-row { flex-direction: column; align-items: stretch; }
    .sort-select { width: 100%; }
}