/* ==========================================================================
   Sartaj Singh Dhatt — Portfolio
   Dark editorial design system: Playfair Display + Inter, espresso + gold/sage
   ========================================================================== */

:root {
  /* Color tokens */
  --bg: #131314;
  --bg-elevated: #1a1a1b;
  --bg-elevated-2: #212123;
  --bg-card: #19191a;

  --text: #eeeeec;
  --text-muted: #a3a1a0;
  --text-faint: #727071;

  --accent: #c9a15a;
  --accent-strong: #dbb56f;
  --accent-soft: rgba(201, 161, 90, 0.14);
  --sage: #8fa37e;
  --sage-soft: rgba(143, 163, 126, 0.16);

  --border: rgba(238, 238, 236, 0.08);
  --border-strong: rgba(238, 238, 236, 0.16);

  --shadow-soft: 0 20px 60px -20px rgba(0, 0, 0, 0.6);

  /* Type scale */
  --font-display: 'Playfair Display', Georgia, serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Spacing scale (density: standard) */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --space-9: 6rem;
  --space-10: 8rem;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 180ms;
  --dur-med: 320ms;

  --container: 1180px;

  color-scheme: dark;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4 { margin: 0; font-family: var(--font-display); font-weight: 600; }
p { margin: 0; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }

::selection { background: var(--accent-soft); color: var(--accent-strong); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--accent);
  color: #141414;
  padding: 0.75rem 1.25rem;
  border-radius: 0 0 8px 0;
  z-index: 999;
  font-weight: 600;
}
.skip-link:focus { left: 0; }

.noise-overlay {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.035;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.icon { width: 1.1em; height: 1.1em; flex-shrink: 0; }

/* ---------- Layout helpers ---------- */
.section-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-9) var(--space-5);
}

.eyebrow {
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-3);
}

.section-title {
  font-size: clamp(1.9rem, 3.6vw, 2.9rem);
  line-height: 1.15;
  max-width: 18ch;
  margin-bottom: var(--space-4);
}

.section-lede {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 62ch;
  line-height: 1.7;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.85rem 1.5rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  transition: transform var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
  white-space: nowrap;
}
.btn .icon { transition: transform var(--dur-fast) var(--ease); }
.btn:hover .icon { transform: translateX(3px); }
.btn:active { transform: scale(0.97); }

.btn-primary {
  background: var(--accent);
  color: #171717;
}
.btn-primary:hover { background: var(--accent-strong); }

.btn-outline {
  background: transparent;
  border: 1px solid var(--border-strong);
  color: var(--text);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent-strong); }

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  padding: 0.6rem 1rem;
  border: 1px solid transparent;
}
.btn-ghost:hover { color: var(--text); border-color: var(--border-strong); }

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  border-bottom: 1px solid transparent;
  transition: background var(--dur-med) var(--ease), border-color var(--dur-med) var(--ease), backdrop-filter var(--dur-med) var(--ease);
}
.site-header.scrolled {
  background: rgba(19, 19, 20, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom-color: var(--border);
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-4) var(--space-5);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
}

.logo {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.main-nav ul {
  display: flex;
  gap: var(--space-6);
}
.main-nav a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-muted);
  position: relative;
  padding: 0.3rem 0.1rem;
  transition: color var(--dur-fast) var(--ease);
}
.main-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  right: 100%;
  bottom: -2px;
  height: 1.5px;
  background: var(--accent);
  transition: right var(--dur-med) var(--ease);
}
.main-nav a:hover { color: var(--text); }
.main-nav a:hover::after,
.main-nav a.active::after { right: 0; }
.main-nav a.active { color: var(--text); }

.header-actions { display: flex; align-items: center; gap: var(--space-3); }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  border-radius: 8px;
}
.nav-toggle-bar {
  width: 20px;
  height: 1.5px;
  background: var(--text);
  transition: transform var(--dur-fast) var(--ease), opacity var(--dur-fast) var(--ease);
  margin: 0 auto;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  padding-top: var(--space-9);
  overflow: hidden;
}

.hero-bg { position: absolute; inset: 0; z-index: 0; }
.hero-glow {
  position: absolute;
  top: -20%;
  right: -10%;
  width: 60vw;
  height: 60vw;
  max-width: 900px;
  max-height: 900px;
  background: radial-gradient(circle, rgba(201, 161, 90, 0.16) 0%, rgba(201, 161, 90, 0) 65%);
  filter: blur(10px);
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(238,238,236,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(238,238,236,0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 70% 60% at 60% 30%, black 10%, transparent 75%);
}

.hero-inner {
  position: relative;
  z-index: 2;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-8) var(--space-5);
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: var(--space-8);
  align-items: center;
  width: 100%;
}

.hero-title {
  font-size: clamp(2.6rem, 6.2vw, 4.6rem);
  line-height: 1.04;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-5);
}

.hero-role {
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  font-weight: 500;
  color: var(--text);
  margin-bottom: var(--space-4);
}

.hero-desc {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 54ch;
  line-height: 1.7;
  margin-bottom: var(--space-6);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

.hero-social { display: flex; gap: var(--space-4); }
.hero-social a {
  width: 42px;
  height: 42px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.hero-social a:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }

/* Portrait */
.hero-portrait { position: relative; justify-self: center; width: 100%; max-width: 380px; }
.portrait-frame {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow-soft);
  aspect-ratio: 4 / 5;
  background: var(--bg-elevated);
}
.portrait-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 12%;
  filter: grayscale(0.55) contrast(1.05) brightness(0.92);
}
.portrait-frame::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(19,19,20,0) 55%, rgba(19,19,20,0.75) 100%);
}

.scroll-cue {
  position: absolute;
  bottom: var(--space-6);
  left: 50%;
  transform: translateX(-50%);
  width: 26px;
  height: 42px;
  border: 1.5px solid var(--border-strong);
  border-radius: 999px;
  z-index: 2;
}
.scroll-cue span {
  position: absolute;
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 8px;
  border-radius: 999px;
  background: var(--accent);
  animation: scrollcue 1.8s var(--ease) infinite;
}
@keyframes scrollcue {
  0% { opacity: 1; top: 8px; }
  70% { opacity: 0; top: 20px; }
  100% { opacity: 0; top: 20px; }
}
@media (prefers-reduced-motion: reduce) { .scroll-cue span { animation: none; } }

/* ---------- Reveal on scroll ---------- */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ---------- About / Brain split ---------- */
.about { background: var(--bg-elevated); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }

.brain-split {
  margin-top: var(--space-8);
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: var(--space-7);
  align-items: stretch;
}

.brain-panel {
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
  transition: border-color var(--dur-med) var(--ease), transform var(--dur-med) var(--ease);
}
.brain-panel:hover { transform: translateY(-4px); }

.brain-kicker {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  margin-bottom: var(--space-4);
}
.brain-left .brain-kicker { color: var(--accent); background: var(--accent-soft); }
.brain-right .brain-kicker { color: var(--sage); background: var(--sage-soft); }
.brain-left:hover { border-color: var(--accent); }
.brain-right:hover { border-color: var(--sage); }

.brain-panel h3 { font-size: 1.4rem; margin-bottom: var(--space-3); }
.brain-panel p { color: var(--text-muted); line-height: 1.7; margin-bottom: var(--space-5); }

.brain-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.brain-tags li {
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  color: var(--text-muted);
}

.brain-divider {
  position: relative;
  width: 2px;
  align-self: stretch;
  justify-self: center;
  background: linear-gradient(180deg, var(--accent), var(--sage));
  border-radius: 2px;
  min-height: 120px;
}
.brain-divider::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 11px;
  height: 11px;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--accent);
}

.lang-strip {
  margin-top: var(--space-7);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-6);
  padding-top: var(--space-6);
  border-top: 1px solid var(--border);
}
.lang-item { display: flex; flex-direction: column; gap: 0.2rem; }
.lang-item strong { font-family: var(--font-display); font-size: 1.1rem; }
.lang-item small { color: var(--text-faint); font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.08em; }

/* ---------- Experience Timeline ---------- */
.experience { position: relative; }

.timeline { position: relative; margin-top: var(--space-8); padding-left: var(--space-7); }

.timeline-line {
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border-strong);
  border-radius: 2px;
  overflow: hidden;
}
.timeline-line-fill {
  display: block;
  width: 100%;
  height: 0%;
  background: linear-gradient(180deg, var(--accent), var(--sage));
  transition: height 0.2s linear;
}

.timeline-item { position: relative; margin-bottom: var(--space-7); }
.timeline-item:last-of-type { margin-bottom: var(--space-6); }

.timeline-dot {
  position: absolute;
  left: -37px;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--accent);
}

.timeline-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: border-color var(--dur-med) var(--ease), transform var(--dur-med) var(--ease);
}
.timeline-card:hover { border-color: var(--border-strong); transform: translateX(4px); }

.timeline-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-2);
}
.timeline-company {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--accent-strong);
  font-size: 1.05rem;
}
.timeline-dates {
  font-size: 0.8rem;
  color: var(--text-faint);
  letter-spacing: 0.03em;
  align-self: center;
}

.timeline-role { font-size: 1.35rem; margin-bottom: var(--space-1); }
.timeline-context { color: var(--text-faint); font-size: 0.88rem; font-style: italic; margin-bottom: var(--space-4); }

.timeline-bullets { display: flex; flex-direction: column; gap: 0.55rem; }
.timeline-bullets li {
  position: relative;
  padding-left: 1.2rem;
  color: var(--text-muted);
  line-height: 1.6;
  font-size: 0.96rem;
}
.timeline-bullets li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--sage);
}

.timeline-end {
  position: relative;
  padding-top: var(--space-2);
  display: flex;
  align-items: center;
  gap: var(--space-4);
}
.timeline-end p { color: var(--text-muted); }
.timeline-end strong { color: var(--text); }
.timeline-dot-current {
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

/* ---------- Education ---------- */
.education { background: var(--bg-elevated); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }

.edu-grid {
  margin-top: var(--space-7);
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-6);
}

.edu-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: border-color var(--dur-med) var(--ease), transform var(--dur-med) var(--ease);
}
.edu-card:hover { border-color: var(--accent); transform: translateY(-4px); }

.edu-card-top { display: flex; align-items: baseline; gap: var(--space-3); margin-bottom: var(--space-2); }
.edu-card-top h3 { font-size: 1.4rem; }
.edu-year {
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
}

.edu-degree { color: var(--text-muted); margin-bottom: var(--space-4); font-size: 0.95rem; }

.edu-list { display: flex; flex-direction: column; gap: 0.55rem; }
.edu-list li {
  position: relative;
  padding-left: 1.2rem;
  color: var(--text-muted);
  font-size: 0.92rem;
  line-height: 1.6;
}
.edu-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
}

/* ---------- Projects ---------- */
.project-grid {
  margin-top: var(--space-7);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: border-color var(--dur-med) var(--ease), box-shadow var(--dur-med) var(--ease);
  transform-style: preserve-3d;
  will-change: transform;
}
.project-card:hover { border-color: var(--border-strong); box-shadow: var(--shadow-soft); }

.project-media {
  aspect-ratio: 4/3;
  background: var(--bg-elevated-2);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  overflow: hidden;
}
.project-media img {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 8px;
  box-shadow: 0 12px 28px -8px rgba(0, 0, 0, 0.5);
}

.project-body { padding: var(--space-5); }
.project-body h3 { font-size: 1.25rem; margin-bottom: var(--space-2); }
.project-body > p { color: var(--text-muted); font-size: 0.92rem; line-height: 1.65; margin-bottom: var(--space-4); }

.project-tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-bottom: var(--space-4); }
.project-tags li {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.28rem 0.6rem;
  border-radius: 999px;
  background: var(--bg-elevated-2);
  color: var(--text-muted);
  border: 1px solid var(--border);
}

.project-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--accent);
}
.project-link .icon { transition: transform var(--dur-fast) var(--ease); }
.project-link:hover .icon { transform: translate(2px, -2px); }

.projects-more { margin-top: var(--space-7); display: flex; justify-content: center; }

/* ---------- Skills ---------- */
.skills-grid {
  margin-top: var(--space-7);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
}
.skill-group h3 {
  font-size: 1rem;
  font-family: var(--font-body);
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 0.82rem;
}
.skill-pills { display: flex; flex-wrap: wrap; gap: 0.55rem; }
.skill-pills li {
  padding: 0.55rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text);
  transition: border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.skill-pills li:hover { border-color: var(--accent); color: var(--accent-strong); transform: translateY(-2px); }

/* ---------- Contact ---------- */
.contact { background: var(--bg-elevated); border-top: 1px solid var(--border); }
.contact-inner { text-align: center; display: flex; flex-direction: column; align-items: center; }
.contact-inner .section-title { max-width: 22ch; }
.contact-inner .section-lede { margin: 0 auto var(--space-7); }

.contact-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-5);
  width: 100%;
  max-width: 880px;
}
.contact-card {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-5);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  text-align: left;
  transition: border-color var(--dur-med) var(--ease), transform var(--dur-med) var(--ease);
}
.contact-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.contact-card .icon { width: 1.4em; height: 1.4em; color: var(--accent); flex-shrink: 0; }
.contact-card-label { display: block; font-size: 0.75rem; color: var(--text-faint); text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 0.2rem; }
.contact-card-value { display: block; font-weight: 600; font-size: 0.92rem; word-break: break-word; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--border); }
.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-5);
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-faint);
  font-size: 0.85rem;
}
.back-to-top {
  width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid var(--border-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.back-to-top:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-portrait { max-width: 320px; justify-self: start; margin-top: var(--space-6); }
  .brain-split { grid-template-columns: 1fr; }
  .brain-divider { width: 60%; height: 2px; min-height: 0; align-self: center; margin: 0 auto; background: linear-gradient(90deg, var(--accent), var(--sage)); }
  .edu-grid { grid-template-columns: 1fr; }
  .project-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-links { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .main-nav {
    position: fixed;
    top: 0;
    right: 0;
    height: 100dvh;
    width: min(78vw, 320px);
    background: var(--bg-elevated);
    border-left: 1px solid var(--border);
    padding: calc(var(--space-9)) var(--space-6) var(--space-6);
    transform: translateX(100%);
    transition: transform var(--dur-med) var(--ease);
    z-index: 90;
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav ul { flex-direction: column; gap: var(--space-5); }
  .main-nav a { font-size: 1.1rem; }
  .nav-toggle { display: flex; }
  .header-actions .btn-ghost span { display: none; }
  .skills-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .section-inner { padding: var(--space-8) var(--space-4); }
  .hero-inner { padding: var(--space-7) var(--space-4); }
  .project-grid { grid-template-columns: 1fr; }
  .timeline { padding-left: var(--space-6); }
  .timeline-dot { left: -31px; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn { justify-content: center; }
  .lang-strip { gap: var(--space-4); }
  .footer-inner { flex-direction: column; gap: var(--space-4); text-align: center; }
}