:root {
  --bg:            #08080F;
  --bg-card:       #0F0F1C;
  --bg-elevated:   #151526;
  --border:        rgba(255,255,255,0.07);
  --border-bright: rgba(255,255,255,0.14);
  --text:          #E2E2F0;
  --text-muted:    #9090B0;
  --text-subtle:   #55557A;
  --accent:        #7C6EF5;
  --accent-text:   #B0A4FF;
  --accent-dim:    rgba(124,110,245,0.10);
  --accent-glow:   rgba(124,110,245,0.18);
  --accent-border: rgba(124,110,245,0.35);
  --orange:        #F97316;
}

[data-theme="light"] {
  --bg:            #F8F8FC;
  --bg-card:       #EEEEF6;
  --bg-elevated:   #E4E4F0;
  --border:        rgba(0,0,0,0.08);
  --border-bright: rgba(0,0,0,0.16);
  --text:          #18182C;
  --text-muted:    #4A4A6E;
  --text-subtle:   #8888AA;
  --accent:        #5B50D6;
  --accent-text:   #4B40C4;
  --accent-dim:    rgba(91,80,214,0.08);
  --accent-glow:   rgba(91,80,214,0.12);
  --accent-border: rgba(91,80,214,0.28);
  --orange:        #EA6C00;
}
[data-theme="light"] body::before {
  background:
    radial-gradient(ellipse 80% 60% at 15% 25%, rgba(91,80,214,0.05) 0%, transparent 65%),
    radial-gradient(ellipse 50% 50% at 85% 75%, rgba(91,80,214,0.03) 0%, transparent 65%);
}
[data-theme="light"] .ds-header.ds-fixed-header {
  background: rgba(248,248,252,0.85);
}
[data-theme="light"] .badge-cisco {
  color: #5B50D6;
}
[data-theme="light"] .badge-yc {
  color: #C25A00;
}
[data-theme="light"] .ds-hero-name {
  background: linear-gradient(140deg, #18182C 35%, #7C6EF5 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
[data-theme="light"] .ds-nav-social a {
  background: rgba(0,0,0,0.04);
}
[data-theme="light"] .ds-hero-photo img {
  box-shadow: 0 12px 40px rgba(0,0,0,0.10), 0 0 0 1px var(--accent-border);
}

/* ─── Reset / Base ───────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
html { background: var(--bg); scroll-behavior: smooth; }
body {
  font-family: 'Inter', sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  font-weight: 400;
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(ellipse 80% 60% at 15% 25%, rgba(124,110,245,0.07) 0%, transparent 65%),
    radial-gradient(ellipse 50% 50% at 85% 75%, rgba(124,110,245,0.04) 0%, transparent 65%);
  pointer-events: none;
}
a { text-decoration: none; color: inherit; transition: color 0.2s ease; }
a:hover { color: var(--accent); }
h1,h2,h3,h4 { font-family: 'Space Grotesk', 'Inter', sans-serif; color: var(--text); margin: 0; }
ul { list-style: none; padding: 0; margin: 0; }
img { max-width: 100%; height: auto; display: block; }
iframe { border: 0; }

/* ─── Header ─────────────────────────────────────────────── */
.ds-header {
  position: fixed; top: 0; width: 100%; z-index: 100;
  padding: 22px 0;
  border-bottom: 1px solid transparent;
  transition: background 0.4s ease, border-color 0.4s ease, backdrop-filter 0.4s ease;
}
.ds-header.ds-fixed-header {
  background: rgba(8,8,15,0.82);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--border);
}
.ds-header-inner { display: flex; justify-content: space-between; align-items: center; }
.ds-header-actions {
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.ds-logo {
  display: flex; align-items: center; gap: 10px;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 13px; font-weight: 600; letter-spacing: 3px;
  text-transform: uppercase; color: var(--text);
}
.ds-logo-mark {
  width: 34px; height: 34px;
  background: var(--accent);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 13px; font-weight: 700; color: #fff; letter-spacing: 0;
  flex-shrink: 0;
}
.ds-logo:hover { color: var(--accent); }
.ds-nav-social {
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  gap: 8px;
}
.ds-nav-social a {
  width: 34px; height: 34px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); font-size: 16px;
  transition: all 0.2s ease;
}
.ds-nav-social a:hover {
  background: var(--accent-dim);
  border-color: var(--accent-border);
  color: #a89af8;
}
.ds-mode-toggle {
  background: none; border: none; padding: 0 4px;
  color: var(--text-subtle); font-size: 15px; cursor: pointer;
  opacity: 0.45; transition: opacity 0.25s ease, color 0.25s ease;
  line-height: 1;
}
.ds-mode-toggle:hover { opacity: 1; color: var(--accent-text); }

/* ─── Hero ───────────────────────────────────────────────── */
.ds-hero {
  min-height: 100vh;
  display: flex; align-items: center;
  padding: 100px 0 80px;
}
.ds-hero-inner {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 72px;
  align-items: center;
  width: 100%;
}
.ds-hero-eyebrow {
  display: inline-block;
  font-size: 11px; font-weight: 700; letter-spacing: 4px;
  text-transform: uppercase; color: var(--accent-text);
  margin-bottom: 20px;
}
.ds-hero-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: clamp(60px, 8vw, 104px);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: -3px;
  background: linear-gradient(140deg, #ffffff 35%, #a89af8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 28px;
}
.ds-hero-tagline {
  font-size: 16px;
  color: var(--text-muted);
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  margin-bottom: 24px;
}
.ds-hero-tagline strong { color: var(--text); font-weight: 500; }
.badge-cisco {
  display: inline-flex; align-items: center; gap: 5px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  color: #a89af8;
  font-size: 10px; font-weight: 700; letter-spacing: 1px;
  padding: 4px 10px; border-radius: 20px; text-transform: uppercase;
}
.badge-yc {
  display: inline-flex; align-items: center; gap: 5px;
  background: rgba(249,115,22,0.10);
  border: 1px solid rgba(249,115,22,0.35);
  color: #fb923c;
  font-size: 10px; font-weight: 700; letter-spacing: 1px;
  padding: 4px 10px; border-radius: 20px; text-transform: uppercase;
}
.ds-hero-stats {
  display: flex; gap: 24px; flex-wrap: wrap;
  margin-bottom: 40px;
}
.ds-hero-stat {
  display: flex; align-items: center; gap: 7px;
  font-size: 13px; color: var(--text-muted); font-weight: 500;
}
.ds-hero-stat i { color: var(--accent); font-size: 15px; }
.ds-hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }

.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--accent); color: #fff;
  font-size: 12px; font-weight: 700; letter-spacing: 1.5px;
  padding: 13px 26px; border-radius: 10px; text-transform: uppercase;
  transition: all 0.2s ease;
}
.btn-primary:hover { background: #6a5ce0; color: #fff; transform: translateY(-2px); box-shadow: 0 8px 24px var(--accent-glow); }
.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px;
  background: transparent; color: var(--text);
  border: 1px solid var(--border-bright);
  font-size: 12px; font-weight: 700; letter-spacing: 1.5px;
  padding: 13px 26px; border-radius: 10px; text-transform: uppercase;
  transition: all 0.2s ease;
}
.btn-secondary:hover { border-color: var(--accent); color: #a89af8; transform: translateY(-2px); }

.ds-hero-photo { position: relative; }
.ds-hero-photo::before {
  content: '';
  position: absolute;
  inset: -30px -20px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 65%);
  border-radius: 28px;
  z-index: 0;
}
.ds-hero-photo img {
  width: 100%; border-radius: 20px;
  border: 1px solid var(--border-bright);
  box-shadow: 0 40px 80px rgba(0,0,0,0.6), 0 0 0 1px var(--accent-border);
  position: relative; z-index: 1;
}

/* ─── Sections ───────────────────────────────────────────── */
.ds-section     { padding: 100px 0; }
.ds-section-alt { background: var(--bg-card); }

.ds-section-label {
  display: block;
  font-size: 11px; font-weight: 700; letter-spacing: 4px;
  text-transform: uppercase; color: var(--accent-text);
  margin-bottom: 10px;
}
.ds-section-title {
  font-size: clamp(30px, 4vw, 44px);
  font-weight: 700; letter-spacing: -1px;
  color: var(--text); margin-bottom: 56px;
}

/* ─── About ──────────────────────────────────────────────── */
.ds-about-text {
  font-size: 21px; line-height: 1.9;
  color: var(--text-muted); font-weight: 300;
  max-width: 820px;
}
.ds-about-text strong { color: var(--text); font-weight: 500; }

/* ─── Skills ─────────────────────────────────────────────── */
.ds-skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px; padding: 24px; height: 100%;
  transition: border-color 0.25s ease;
}
.ds-skill-card:hover { border-color: var(--border-bright); }
.ds-skill-card-label {
  display: block;
  font-size: 10px; font-weight: 700; letter-spacing: 3px;
  text-transform: uppercase; color: var(--accent-text); margin-bottom: 16px;
}
.ds-pill-wrap { display: flex; flex-wrap: wrap; gap: 8px; }
.ds-pill {
  font-size: 13px; font-weight: 500; color: var(--text-muted);
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 6px; padding: 5px 12px;
  transition: all 0.2s ease;
}
.ds-pill:hover { background: var(--accent-dim); border-color: var(--accent-border); color: #a89af8; }

/* ─── Experience & Education ─────────────────────────────── */
.ds-entries { padding-top: 0; }
.ds-entry {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 40px;
  padding: 40px 0;
  border-bottom: 1px solid var(--border);
}
.ds-entry:first-child { padding-top: 0; }
.ds-entry:last-child { border-bottom: none; padding-bottom: 0; }
.ds-entry-year {
  font-size: 12px; font-weight: 600; letter-spacing: 0.5px;
  color: var(--accent-text); line-height: 1.6; padding-top: 3px;
}
.ds-entry-company {
  font-size: 22px; font-weight: 600; color: var(--text);
  margin-bottom: 4px; line-height: 1.3;
}
.ds-entry-company small { font-size: 14px; color: var(--text-muted); font-weight: 400; }
.ds-entry-role {
  display: block; font-size: 16px; font-weight: 500;
  color: var(--text); margin-bottom: 4px;
}
.ds-entry-location {
  display: block; font-size: 13px; color: var(--text-subtle);
  margin-bottom: 20px;
}
.ds-entry-details {
  font-size: 15px; line-height: 1.8; color: var(--text-muted);
  margin: 0; font-style: italic;
}
.ds-bullets { margin: 0; }
.ds-bullets li {
  font-size: 15px; line-height: 1.8; color: var(--text-muted);
  padding-left: 20px; position: relative; margin-bottom: 12px;
}
.ds-bullets li::before {
  content: '—'; position: absolute; left: 0;
  color: var(--accent); font-weight: 600; font-size: 12px;
}

/* ─── Projects ───────────────────────────────────────────── */
.ds-project {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px; padding: 40px; margin-bottom: 20px;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}
.ds-project:hover {
  border-color: var(--border-bright);
  box-shadow: 0 40px 80px rgba(0,0,0,0.6), 0 0 0 1px var(--accent-border);
}
[data-theme="light"] .ds-project:hover {
  box-shadow: 0 12px 40px rgba(0,0,0,0.10), 0 0 0 1px var(--accent-border);
}
.ds-project-title {
  display: block; font-size: 24px; font-weight: 700; color: var(--text);
  margin-bottom: 14px; transition: color 0.2s ease;
}
.ds-project-title:hover { color: var(--accent); }
.ds-project-desc {
  font-size: 15px; line-height: 1.8; color: var(--text-muted); margin-bottom: 10px;
}
.ds-video-wrap {
  position: relative; padding-top: 56.25%; border-radius: 10px;
  overflow: hidden; border: 1px solid var(--border);
}
.ds-video-wrap iframe { position: absolute; inset: 0; width: 100%; height: 100%; }

/* ─── Sub-page (project detail) ─────────────────────────── */
.ds-main-section {
  padding-top: 100px; padding-bottom: 80px;
}
.ds-main-section h2 {
  font-size: 22px; font-weight: 700; margin: 40px 0 14px; color: var(--text);
}
.ds-main-section h3 {
  font-size: 17px; font-weight: 600; margin: 28px 0 10px; color: var(--text);
}
.ds-main-section p {
  color: var(--text-muted); line-height: 1.8; margin-bottom: 16px;
}
.ds-main-section figure {
  margin: 28px 0; text-align: center;
}
.ds-main-section figure img {
  border-radius: 8px; border: 1px solid var(--border);
}
figcaption {
  font-size: 13px; color: var(--text-subtle); margin-top: 10px; font-style: italic;
}
.ds-back-btn {
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--text-muted); font-size: 14px; font-weight: 500;
  margin-bottom: 40px; transition: color 0.2s ease;
  white-space: nowrap;
}
.ds-back-btn span { white-space: nowrap; }
.ds-back-btn:hover { color: var(--accent); }
.ds-detail-title {
  font-size: clamp(28px, 4vw, 42px); font-weight: 700; letter-spacing: -1px;
  color: var(--text); margin-bottom: 8px;
}
.ds-detail-meta {
  font-size: 13px; color: var(--accent-text); font-weight: 600;
  letter-spacing: 2px; text-transform: uppercase; margin-bottom: 32px; display: block;
}
.ds-equation-block {
  margin: 8px 0 20px;
  padding: 14px 18px;
  font-family: ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  font-size: 14px;
  line-height: 1.65;
  color: var(--text);
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  border-radius: 8px;
}

/* ─── Footer ─────────────────────────────────────────────── */
.ds-footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border);
  padding: 80px 0 40px; text-align: center;
}
.ds-footer-eyebrow {
  display: block; font-size: 11px; font-weight: 700;
  letter-spacing: 4px; text-transform: uppercase;
  color: var(--accent-text); margin-bottom: 14px;
}
.ds-footer-heading {
  font-size: clamp(38px, 5vw, 60px); font-weight: 700;
  letter-spacing: -1.5px; color: var(--text); margin-bottom: 14px;
}
.ds-footer-sub { font-size: 16px; color: var(--text-muted); margin-bottom: 32px; }
.ds-footer-links {
  display: flex; justify-content: center; gap: 28px;
  flex-wrap: wrap; margin-bottom: 40px;
}
.ds-footer-links a {
  display: inline-flex; align-items: center; gap: 7px;
  font-size: 14px; color: var(--text-muted); font-weight: 500;
  transition: color 0.2s ease;
}
.ds-footer-links a:hover { color: var(--accent); }
.ds-footer-links i { font-size: 16px; }
.ds-footer-divider { border: none; border-top: 1px solid var(--border); margin: 40px 0 24px; }
.ds-copyright { font-size: 12px; color: var(--text-subtle); letter-spacing: 0.5px; }
.ds-copyright a { color: var(--text-subtle); }
.ds-copyright a:hover { color: var(--accent); }

/* ─── Responsive ─────────────────────────────────────────── */
@media (max-width: 768px) {
  .ds-hero { padding: 80px 0 60px; min-height: unset; }
  .ds-hero-inner { grid-template-columns: 1fr; gap: 48px; }
  .ds-hero-photo { max-width: 280px; margin: 0 auto; order: -1; }
  .ds-hero-photo::before { display: none; }
  .ds-hero-name { font-size: clamp(52px, 14vw, 72px); letter-spacing: -2px; }
  .ds-hero-tagline { font-size: 14px; }
  .ds-section { padding: 64px 0; }
  .ds-section-title { margin-bottom: 36px; }
  .ds-about-text { font-size: 17px; }
  .ds-entry { grid-template-columns: 1fr; gap: 10px; }
  .ds-entry-year { padding-top: 0; }
  .ds-project { padding: 24px; }
  .ds-footer { padding: 60px 0 32px; }
  .ds-footer-heading { font-size: 36px; }
}
@media (min-width: 769px) and (max-width: 1024px) {
  .ds-hero-inner { grid-template-columns: 1fr 300px; gap: 48px; }
  .ds-entry { grid-template-columns: 160px 1fr; gap: 28px; }
}