/* ==========================================================================
   Priyanshu Kumar — Portfolio
   Design system: dark-first, electric-cyan accent, glassmorphism, 3D + parallax
   ========================================================================== */

/* ----------  Design tokens  ---------- */
:root {
  /* Accent (electric cyan / sky) */
  --accent:        #22d3ee;
  --accent-2:      #38bdf8;
  --accent-3:      #6366f1;
  --accent-soft:   rgba(34, 211, 238, 0.14);
  --accent-glow:   rgba(34, 211, 238, 0.45);
  --gradient:      linear-gradient(120deg, #22d3ee 0%, #38bdf8 45%, #6366f1 100%);
  --gradient-text: linear-gradient(120deg, #67e8f9 0%, #38bdf8 55%, #818cf8 100%);

  /* Dark theme (default) */
  --bg:            #05070d;
  --bg-2:          #090d18;
  --bg-3:          #0c1120;
  --surface:       rgba(255, 255, 255, 0.035);
  --surface-2:     rgba(255, 255, 255, 0.06);
  --surface-hi:    rgba(255, 255, 255, 0.09);
  --border:        rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.16);
  --text:          #e8eefb;
  --text-muted:    #9aa7bd;
  --text-dim:      #67748d;
  --shadow:        0 20px 50px -20px rgba(0, 0, 0, 0.7);
  --shadow-glow:   0 0 40px -8px var(--accent-glow);
  --nav-bg:        rgba(8, 11, 22, 0.66);

  /* Type */
  --font-sans:    "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-display: "Space Grotesk", var(--font-sans);
  --font-mono:    "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;

  /* Layout */
  --maxw: 1180px;
  --gutter: clamp(1.1rem, 4vw, 2.5rem);
  --radius: 18px;
  --radius-sm: 12px;
  --radius-lg: 26px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

[data-theme="light"] {
  --accent:        #0891b2;
  --accent-2:      #0284c7;
  --accent-3:      #4f46e5;
  --accent-soft:   rgba(8, 145, 178, 0.12);
  --accent-glow:   rgba(8, 145, 178, 0.30);
  --gradient-text: linear-gradient(120deg, #0e7490 0%, #0284c7 55%, #4f46e5 100%);

  --bg:            #f5f8fd;
  --bg-2:          #eef3fa;
  --bg-3:          #e7eef8;
  --surface:       rgba(255, 255, 255, 0.72);
  --surface-2:     rgba(255, 255, 255, 0.85);
  --surface-hi:    #ffffff;
  --border:        rgba(8, 18, 38, 0.10);
  --border-strong: rgba(8, 18, 38, 0.18);
  --text:          #0b1220;
  --text-muted:    #45526a;
  --text-dim:      #6b7890;
  --shadow:        0 18px 44px -22px rgba(15, 30, 60, 0.30);
  --nav-bg:        rgba(245, 248, 253, 0.72);
}

/* ----------  Reset / base  ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
html:focus-within { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: clamp(1rem, 0.96rem + 0.2vw, 1.075rem);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  transition: background 0.5s var(--ease), color 0.4s var(--ease);
}

/* Ambient background wash */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(60% 50% at 78% 8%, rgba(56,189,248,0.10), transparent 60%),
    radial-gradient(55% 45% at 12% 22%, rgba(99,102,241,0.10), transparent 55%),
    radial-gradient(50% 50% at 50% 100%, rgba(34,211,238,0.07), transparent 60%);
  pointer-events: none;
}
[data-theme="light"] body::before { opacity: 0.6; }

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; border: none; background: none; }
ul { list-style: none; padding: 0; }

::selection { background: var(--accent); color: #04121a; }

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

/* Scrollbar */
::-webkit-scrollbar { width: 11px; height: 11px; }
::-webkit-scrollbar-track { background: var(--bg-2); }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 99px; border: 3px solid var(--bg-2); }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

/* ----------  Layout helpers  ---------- */
.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }
section { position: relative; padding-block: clamp(4.5rem, 10vw, 8rem); }
.section-narrow { max-width: 820px; }

.eyebrow {
  display: inline-flex; align-items: center; gap: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.78rem; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--accent); margin-bottom: 1.1rem; font-weight: 500;
}
.eyebrow::before {
  content: ""; width: 26px; height: 1px;
  background: linear-gradient(90deg, var(--accent), transparent);
}

.section-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.9rem, 1.2rem + 3vw, 3rem);
  line-height: 1.08; letter-spacing: -0.02em;
  margin-bottom: 1rem;
}
.section-lead { color: var(--text-muted); max-width: 60ch; font-size: 1.05rem; }
.gradient-text {
  background: var(--gradient-text);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}

/* ----------  Buttons  ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 0.55rem;
  padding: 0.8rem 1.4rem; border-radius: 999px;
  font-weight: 600; font-size: 0.95rem; letter-spacing: 0.01em;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), background 0.25s, border-color 0.25s, color 0.25s;
  will-change: transform; white-space: nowrap;
}
.btn svg { width: 18px; height: 18px; }
.btn-primary {
  background: var(--gradient); color: #04121a;
  box-shadow: 0 10px 30px -12px var(--accent-glow);
}
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 16px 38px -10px var(--accent-glow); }
.btn-ghost {
  background: var(--surface); color: var(--text);
  border: 1px solid var(--border-strong); backdrop-filter: blur(10px);
}
.btn-ghost:hover { transform: translateY(-3px); border-color: var(--accent); color: var(--accent); }

/* ----------  Glass card  ---------- */
.glass {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
}

/* ==========================================================================
   NAVBAR
   ========================================================================== */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  transition: padding 0.35s var(--ease), background 0.35s, border-color 0.35s, backdrop-filter 0.35s;
  border-bottom: 1px solid transparent;
}
.nav__inner {
  max-width: var(--maxw); margin-inline: auto; padding: 1.15rem var(--gutter);
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  transition: padding 0.35s var(--ease);
}
.nav.scrolled {
  background: var(--nav-bg);
  backdrop-filter: blur(16px) saturate(160%);
  -webkit-backdrop-filter: blur(16px) saturate(160%);
  border-bottom-color: var(--border);
}
.nav.scrolled .nav__inner { padding-block: 0.7rem; }

.brand { display: inline-flex; align-items: center; gap: 0.65rem; font-family: var(--font-display); font-weight: 600; font-size: 1.05rem; letter-spacing: -0.01em; }
.brand__mark {
  width: 38px; height: 38px; border-radius: 11px; display: grid; place-items: center;
  background: var(--gradient); color: #04121a; font-weight: 700; font-size: 0.95rem;
  box-shadow: 0 6px 18px -6px var(--accent-glow);
}
.brand span.dim { color: var(--text-dim); font-weight: 400; }

.nav__links { display: flex; align-items: center; gap: 0.35rem; }
.nav__links a {
  padding: 0.5rem 0.9rem; border-radius: 999px; font-size: 0.92rem; color: var(--text-muted);
  font-weight: 500; transition: color 0.2s, background 0.2s;
}
.nav__links a:hover, .nav__links a.active { color: var(--text); background: var(--surface-2); }

.nav__actions { display: flex; align-items: center; gap: 0.6rem; }
.icon-btn {
  width: 42px; height: 42px; border-radius: 12px; display: grid; place-items: center;
  background: var(--surface); border: 1px solid var(--border);
  color: var(--text); transition: transform 0.2s, border-color 0.2s, color 0.2s, background 0.2s;
}
.icon-btn:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }
.icon-btn svg { width: 19px; height: 19px; }
.theme-toggle .sun { display: none; }
[data-theme="light"] .theme-toggle .sun { display: block; }
[data-theme="light"] .theme-toggle .moon { display: none; }

.nav__cta { display: inline-flex; }
.hamburger { display: none; }

/* Mobile nav */
@media (max-width: 880px) {
  .nav__links, .nav__cta { display: none; }
  .hamburger { display: grid; }
  .nav__menu {
    position: fixed; inset: 0 0 0 auto; width: min(82vw, 340px); z-index: 99;
    background: var(--bg-2); border-left: 1px solid var(--border);
    padding: 6rem 1.6rem 2rem; transform: translateX(100%);
    transition: transform 0.45s var(--ease); display: flex; flex-direction: column; gap: 0.4rem;
    box-shadow: -30px 0 60px -30px rgba(0,0,0,0.6);
  }
  .nav__menu.open { transform: translateX(0); }
  .nav__menu a { padding: 0.95rem 1rem; border-radius: 12px; font-size: 1.05rem; color: var(--text-muted); font-weight: 500; }
  .nav__menu a:hover { background: var(--surface-2); color: var(--text); }
  .nav__menu .btn { margin-top: 1rem; justify-content: center; }
  .menu-backdrop { position: fixed; inset: 0; z-index: 98; background: rgba(0,0,0,0.5); opacity: 0; visibility: hidden; transition: opacity 0.35s; backdrop-filter: blur(2px); }
  .menu-backdrop.open { opacity: 1; visibility: visible; }
}
@media (min-width: 881px) { .nav__menu, .menu-backdrop { display: none; } }

/* ==========================================================================
   HERO
   ========================================================================== */
.hero { min-height: 100svh; display: flex; align-items: center; padding-top: 6rem; overflow: hidden; }
#hero-canvas {
  position: absolute; inset: 0; z-index: -1; width: 100%; height: 100%;
  opacity: 0; transition: opacity 1.4s var(--ease);
}
#hero-canvas.ready { opacity: 1; }
.hero::after { /* fade canvas into page bottom */
  content: ""; position: absolute; inset: auto 0 0 0; height: 36%; z-index: -1;
  background: linear-gradient(to top, var(--bg), transparent);
  pointer-events: none;
}
.hero__orb { position: absolute; border-radius: 50%; filter: blur(70px); opacity: 0.55; z-index: -1; pointer-events: none; }
.hero__orb--1 { width: 420px; height: 420px; background: radial-gradient(circle, rgba(34,211,238,0.5), transparent 70%); top: -80px; right: -60px; }
.hero__orb--2 { width: 360px; height: 360px; background: radial-gradient(circle, rgba(99,102,241,0.45), transparent 70%); bottom: -40px; left: -80px; }

.hero__content { max-width: 760px; }
.hero__eyebrow {
  display: inline-flex; align-items: center; gap: 0.6rem; padding: 0.45rem 0.95rem;
  border-radius: 999px; background: var(--surface); border: 1px solid var(--border);
  backdrop-filter: blur(10px); font-size: 0.84rem; color: var(--text-muted); margin-bottom: 1.6rem;
  font-family: var(--font-mono); letter-spacing: 0.02em;
}
.status-dot { width: 8px; height: 8px; border-radius: 50%; background: #34d399; box-shadow: 0 0 0 0 rgba(52,211,153,0.6); animation: pulse 2.4s infinite; }
@keyframes pulse { 0% { box-shadow: 0 0 0 0 rgba(52,211,153,0.55); } 70% { box-shadow: 0 0 0 9px rgba(52,211,153,0); } 100% { box-shadow: 0 0 0 0 rgba(52,211,153,0); } }

.hero h1 {
  font-family: var(--font-display); font-weight: 600;
  font-size: clamp(2.7rem, 1.4rem + 6.2vw, 5.4rem); line-height: 0.98; letter-spacing: -0.03em;
  margin-bottom: 1.2rem;
}
.hero h1 .line { display: block; }
.hero__role {
  font-family: var(--font-mono); font-size: clamp(0.95rem, 0.85rem + 0.5vw, 1.2rem);
  color: var(--text-muted); margin-bottom: 1.5rem; letter-spacing: 0.01em;
}
.hero__role b { color: var(--accent); font-weight: 500; }
.hero__blurb { font-size: clamp(1.02rem, 0.98rem + 0.3vw, 1.2rem); color: var(--text-muted); max-width: 60ch; margin-bottom: 2.2rem; }
.hero__cta { display: flex; flex-wrap: wrap; gap: 0.9rem; }

.scroll-cue {
  position: absolute; bottom: 2rem; left: 50%; transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: 0.5rem;
  font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.2em; text-transform: uppercase; color: var(--text-dim);
}
.scroll-cue .mouse { width: 24px; height: 38px; border: 1.5px solid var(--border-strong); border-radius: 14px; position: relative; }
.scroll-cue .mouse::after { content: ""; position: absolute; top: 7px; left: 50%; transform: translateX(-50%); width: 4px; height: 7px; background: var(--accent); border-radius: 2px; animation: wheel 1.8s infinite; }
@keyframes wheel { 0% { opacity: 0; transform: translate(-50%, 0); } 40% { opacity: 1; } 80% { opacity: 0; transform: translate(-50%, 12px); } 100% { opacity: 0; } }

/* ==========================================================================
   STATS BAND
   ========================================================================== */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; }
.stat { padding: 1.7rem 1.5rem; border-radius: var(--radius); text-align: left; position: relative; overflow: hidden; }
.stat::before { content: ""; position: absolute; inset: 0; background: var(--gradient); opacity: 0; transition: opacity 0.4s; }
.stat:hover::before { opacity: 0.06; }
.stat__num { font-family: var(--font-display); font-weight: 600; font-size: clamp(2rem, 1.4rem + 2vw, 3rem); line-height: 1; letter-spacing: -0.02em; }
.stat__num .gradient-text { display: inline-block; }
.stat__label { color: var(--text-muted); font-size: 0.92rem; margin-top: 0.55rem; }
@media (max-width: 760px) { .stats { grid-template-columns: repeat(2, 1fr); } }

/* ==========================================================================
   ABOUT
   ========================================================================== */
.about__grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: clamp(2rem, 5vw, 4rem); align-items: center; }
.about__body p { color: var(--text-muted); margin-bottom: 1.1rem; }
.about__body strong { color: var(--text); font-weight: 600; }
.about__quote {
  margin-top: 1.8rem; padding: 1.2rem 1.5rem; border-left: 2px solid var(--accent);
  background: var(--accent-soft); border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-style: italic; color: var(--text); font-size: 1.02rem;
}
.about__quote cite { display: block; margin-top: 0.5rem; font-style: normal; font-size: 0.85rem; color: var(--text-dim); }
.about__portrait { position: relative; justify-self: center; }
.about__portrait img { width: min(300px, 70vw); aspect-ratio: 1; object-fit: cover; border-radius: var(--radius-lg); border: 1px solid var(--border-strong); }
.about__portrait::before { content: ""; position: absolute; inset: -14px; border-radius: calc(var(--radius-lg) + 14px); background: var(--gradient); opacity: 0.25; filter: blur(26px); z-index: -1; }
.about__chips { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 1.6rem; }
.chip {
  font-family: var(--font-mono); font-size: 0.8rem; padding: 0.4rem 0.85rem; border-radius: 999px;
  background: var(--surface-2); border: 1px solid var(--border); color: var(--text-muted);
}
@media (max-width: 800px) { .about__grid { grid-template-columns: 1fr; } .about__portrait { order: -1; } }

/* ==========================================================================
   EXPERIENCE — timeline
   ========================================================================== */
.timeline { position: relative; margin-top: 1rem; }
.timeline::before { content: ""; position: absolute; left: 19px; top: 6px; bottom: 6px; width: 2px; background: linear-gradient(var(--accent), transparent); opacity: 0.5; }
.tl-item { position: relative; padding-left: 60px; padding-bottom: 2.4rem; }
.tl-item:last-child { padding-bottom: 0; }
.tl-dot { position: absolute; left: 9px; top: 4px; width: 22px; height: 22px; border-radius: 50%; background: var(--bg); border: 2px solid var(--accent); display: grid; place-items: center; }
.tl-dot::after { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 12px var(--accent-glow); }
.tl-card { padding: 1.5rem 1.6rem; border-radius: var(--radius); transition: transform 0.3s var(--ease), border-color 0.3s; }
.tl-card:hover { transform: translateX(5px); border-color: var(--border-strong); }
.tl-head { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 1rem; align-items: baseline; margin-bottom: 0.2rem; }
.tl-role { font-family: var(--font-display); font-weight: 600; font-size: 1.15rem; }
.tl-date { font-family: var(--font-mono); font-size: 0.8rem; color: var(--accent); white-space: nowrap; }
.tl-org { color: var(--text-muted); font-size: 0.95rem; margin-bottom: 0.9rem; }
.tl-org b { color: var(--text); font-weight: 600; }
.tl-list { display: flex; flex-direction: column; gap: 0.55rem; }
.tl-list li { position: relative; padding-left: 1.3rem; color: var(--text-muted); font-size: 0.96rem; }
.tl-list li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }
@media (max-width: 540px) { .tl-item { padding-left: 48px; } }

/* ==========================================================================
   PROJECTS
   ========================================================================== */
.proj-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.3rem; }
.proj-card {
  position: relative; padding: 1.7rem; border-radius: var(--radius); overflow: hidden;
  display: flex; flex-direction: column; gap: 0.9rem; cursor: pointer;
  transition: transform 0.35s var(--ease), border-color 0.35s, box-shadow 0.35s;
}
.proj-card::after { content: ""; position: absolute; inset: 0; border-radius: inherit; padding: 1px; background: var(--gradient); -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0); -webkit-mask-composite: xor; mask-composite: exclude; opacity: 0; transition: opacity 0.35s; pointer-events: none; }
.proj-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.proj-card:hover::after { opacity: 0.8; }
.proj-card__top { display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem; }
.proj-icon { width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center; background: var(--accent-soft); color: var(--accent); flex-shrink: 0; }
.proj-icon svg { width: 24px; height: 24px; }
.proj-period { font-family: var(--font-mono); font-size: 0.74rem; color: var(--text-dim); }
.proj-card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.25rem; letter-spacing: -0.01em; }
.proj-card p { color: var(--text-muted); font-size: 0.95rem; flex-grow: 1; }
.proj-tags { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.proj-tag { font-family: var(--font-mono); font-size: 0.72rem; padding: 0.28rem 0.62rem; border-radius: 7px; background: var(--surface-2); border: 1px solid var(--border); color: var(--text-muted); }
.proj-more { display: inline-flex; align-items: center; gap: 0.4rem; font-size: 0.86rem; font-weight: 600; color: var(--accent); margin-top: 0.2rem; }
.proj-more svg { width: 15px; height: 15px; transition: transform 0.25s; }
.proj-card:hover .proj-more svg { transform: translate(3px, -3px); }
@media (max-width: 720px) { .proj-grid { grid-template-columns: 1fr; } }

/* Earlier work */
.earlier { margin-top: 2.4rem; }
.earlier h3 { font-family: var(--font-mono); font-size: 0.82rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-dim); margin-bottom: 1.1rem; }
.earlier-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 0.8rem; }
.earlier-item { padding: 0.95rem 1.1rem; border-radius: var(--radius-sm); display: flex; align-items: center; gap: 0.7rem; transition: border-color 0.25s, transform 0.25s; }
.earlier-item:hover { border-color: var(--accent); transform: translateY(-3px); }
.earlier-item svg { width: 18px; height: 18px; color: var(--accent); flex-shrink: 0; }
.earlier-item span { font-size: 0.9rem; }
.earlier-item small { display: block; color: var(--text-dim); font-size: 0.74rem; font-family: var(--font-mono); }

/* Project modal */
.modal-backdrop { position: fixed; inset: 0; z-index: 200; background: rgba(3,6,14,0.74); backdrop-filter: blur(6px); display: grid; place-items: center; padding: 1.5rem; opacity: 0; visibility: hidden; transition: opacity 0.3s; }
.modal-backdrop.open { opacity: 1; visibility: visible; }
.modal {
  width: min(640px, 100%); max-height: 86vh; overflow-y: auto; border-radius: var(--radius-lg);
  background: var(--bg-2); border: 1px solid var(--border-strong); padding: clamp(1.6rem, 4vw, 2.6rem);
  transform: translateY(24px) scale(0.98); transition: transform 0.4s var(--ease); position: relative;
}
.modal-backdrop.open .modal { transform: translateY(0) scale(1); }
.modal__close { position: absolute; top: 1.1rem; right: 1.1rem; width: 40px; height: 40px; border-radius: 11px; background: var(--surface-2); border: 1px solid var(--border); display: grid; place-items: center; }
.modal__close:hover { color: var(--accent); border-color: var(--accent); }
.modal__icon { width: 56px; height: 56px; border-radius: 15px; display: grid; place-items: center; background: var(--accent-soft); color: var(--accent); margin-bottom: 1.1rem; }
.modal__icon svg { width: 30px; height: 30px; }
.modal h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.6rem; margin-bottom: 0.3rem; }
.modal__period { font-family: var(--font-mono); font-size: 0.8rem; color: var(--accent); margin-bottom: 1.2rem; }
.modal__body { color: var(--text-muted); }
.modal__body p { margin-bottom: 1rem; }
.modal__body h4 { color: var(--text); font-size: 0.95rem; margin: 1.4rem 0 0.6rem; font-family: var(--font-display); }
.modal__body ul { display: flex; flex-direction: column; gap: 0.55rem; }
.modal__body li { position: relative; padding-left: 1.4rem; }
.modal__body li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }
.modal__tags { display: flex; flex-wrap: wrap; gap: 0.45rem; margin-top: 1.5rem; }

/* ==========================================================================
   SKILLS
   ========================================================================== */
.skills-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.2rem; }
.skill-group { padding: 1.6rem 1.7rem; border-radius: var(--radius); }
.skill-group__head { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 1.2rem; }
.skill-group__icon { width: 40px; height: 40px; border-radius: 11px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; }
.skill-group__icon svg { width: 21px; height: 21px; }
.skill-group h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.1rem; }
.skill-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.skill-tags span { font-size: 0.86rem; padding: 0.4rem 0.8rem; border-radius: 9px; background: var(--surface-2); border: 1px solid var(--border); color: var(--text-muted); transition: color 0.2s, border-color 0.2s, transform 0.2s; }
.skill-tags span:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }
@media (max-width: 720px) { .skills-grid { grid-template-columns: 1fr; } }

/* ==========================================================================
   EDUCATION
   ========================================================================== */
.edu-card { display: flex; gap: 1.5rem; padding: 1.8rem; border-radius: var(--radius); align-items: flex-start; }
.edu-card__logo { width: 56px; height: 56px; border-radius: 14px; background: var(--gradient); color: #04121a; display: grid; place-items: center; font-family: var(--font-display); font-weight: 700; flex-shrink: 0; }
.edu-card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.2rem; }
.edu-card .deg { color: var(--accent); font-size: 0.95rem; margin: 0.2rem 0 0.5rem; }
.edu-card .meta { font-family: var(--font-mono); font-size: 0.8rem; color: var(--text-dim); }
.edu-card p { color: var(--text-muted); font-size: 0.94rem; margin-top: 0.7rem; }
@media (max-width: 540px) { .edu-card { flex-direction: column; gap: 1rem; } }

/* ==========================================================================
   WRITING / blog teaser
   ========================================================================== */
.posts-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.2rem; }
.post-card { display: flex; flex-direction: column; border-radius: var(--radius); overflow: hidden; transition: transform 0.35s var(--ease), border-color 0.35s, box-shadow 0.35s; }
.post-card:hover { transform: translateY(-6px); border-color: var(--border-strong); box-shadow: var(--shadow); }
.post-card__cover { aspect-ratio: 16 / 9; position: relative; display: grid; place-items: center; overflow: hidden; }
.post-card__cover .cover-art { position: absolute; inset: 0; }
.post-card__cover .cover-tag { position: relative; font-family: var(--font-mono); font-size: 0.74rem; color: #04121a; background: rgba(255,255,255,0.86); padding: 0.3rem 0.7rem; border-radius: 999px; letter-spacing: 0.05em; }
.post-card__body { padding: 1.3rem 1.4rem; display: flex; flex-direction: column; gap: 0.55rem; flex-grow: 1; }
.post-card__date { font-family: var(--font-mono); font-size: 0.76rem; color: var(--text-dim); }
.post-card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.12rem; line-height: 1.25; }
.post-card p { color: var(--text-muted); font-size: 0.9rem; flex-grow: 1; }
.post-card__read { font-size: 0.84rem; font-weight: 600; color: var(--accent); display: inline-flex; align-items: center; gap: 0.35rem; }
@media (max-width: 860px) { .posts-grid { grid-template-columns: 1fr; } }

.section-head-row { display: flex; align-items: flex-end; justify-content: space-between; gap: 1rem; flex-wrap: wrap; margin-bottom: 2.4rem; }

/* ==========================================================================
   CONTACT
   ========================================================================== */
.contact { text-align: center; }
.contact__inner { max-width: 720px; margin-inline: auto; padding: clamp(2.2rem, 5vw, 3.8rem); border-radius: var(--radius-lg); position: relative; overflow: hidden; }
.contact__inner::before { content: ""; position: absolute; inset: 0; background: var(--gradient); opacity: 0.06; }
.contact h2 { font-family: var(--font-display); font-weight: 600; font-size: clamp(1.9rem, 1.2rem + 3vw, 3rem); letter-spacing: -0.02em; margin-bottom: 1rem; }
.contact p { color: var(--text-muted); margin-bottom: 2rem; }
.contact__mail { font-family: var(--font-display); font-size: clamp(1.1rem, 0.9rem + 1.5vw, 1.8rem); font-weight: 500; display: inline-block; margin-bottom: 2rem; }
.contact__mail:hover { color: var(--accent); }
.socials { display: flex; justify-content: center; flex-wrap: wrap; gap: 0.8rem; }
.social-link { display: inline-flex; align-items: center; gap: 0.5rem; padding: 0.7rem 1.2rem; border-radius: 999px; background: var(--surface); border: 1px solid var(--border); font-size: 0.92rem; transition: transform 0.25s, border-color 0.25s, color 0.25s; }
.social-link:hover { transform: translateY(-3px); border-color: var(--accent); color: var(--accent); }
.social-link svg { width: 18px; height: 18px; }

/* ==========================================================================
   FOOTER
   ========================================================================== */
.footer { border-top: 1px solid var(--border); padding-block: 2.4rem; }
.footer__inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }
.footer__meta { color: var(--text-dim); font-size: 0.85rem; }
.footer__top { display: inline-flex; align-items: center; gap: 0.5rem; font-size: 0.85rem; color: var(--text-muted); }
.footer__top:hover { color: var(--accent); }

/* ==========================================================================
   SCROLL REVEAL + PARALLAX
   ========================================================================== */
.reveal { opacity: 0; transform: translateY(34px); transition: opacity 0.8s var(--ease), transform 0.8s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
.reveal-delay-1 { transition-delay: 0.08s; }
.reveal-delay-2 { transition-delay: 0.16s; }
.reveal-delay-3 { transition-delay: 0.24s; }
[data-parallax] { will-change: transform; }

/* ==========================================================================
   BLOG LISTING PAGE
   ========================================================================== */
.page-hero { padding-top: 9rem; padding-bottom: 2rem; }
.page-hero h1 { font-family: var(--font-display); font-weight: 600; font-size: clamp(2.2rem, 1.4rem + 3.5vw, 3.6rem); letter-spacing: -0.02em; margin-bottom: 0.8rem; }
.page-hero p { color: var(--text-muted); max-width: 60ch; }

.blog-toolbar { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 2.4rem; }
.filter-btn { font-family: var(--font-mono); font-size: 0.8rem; padding: 0.45rem 0.95rem; border-radius: 999px; background: var(--surface); border: 1px solid var(--border); color: var(--text-muted); transition: all 0.2s; }
.filter-btn:hover { color: var(--text); }
.filter-btn.active { background: var(--accent); color: #04121a; border-color: var(--accent); font-weight: 600; }

.blog-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(310px, 1fr)); gap: 1.4rem; }
.blog-empty { text-align: center; color: var(--text-dim); padding: 4rem 1rem; font-family: var(--font-mono); }

/* ==========================================================================
   BLOG POST PAGE
   ========================================================================== */
.post-wrap { max-width: 760px; margin-inline: auto; padding-top: 8rem; }
.post-back { display: inline-flex; align-items: center; gap: 0.4rem; font-family: var(--font-mono); font-size: 0.82rem; color: var(--text-muted); margin-bottom: 1.8rem; }
.post-back:hover { color: var(--accent); }
.post-header { margin-bottom: 2.4rem; padding-bottom: 2rem; border-bottom: 1px solid var(--border); }
.post-header h1 { font-family: var(--font-display); font-weight: 600; font-size: clamp(2rem, 1.4rem + 3vw, 3.2rem); line-height: 1.1; letter-spacing: -0.02em; margin-bottom: 1rem; }
.post-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 0.8rem; font-family: var(--font-mono); font-size: 0.82rem; color: var(--text-dim); }
.post-meta .dot { width: 3px; height: 3px; border-radius: 50%; background: var(--text-dim); }
.post-meta .tags { display: flex; gap: 0.4rem; flex-wrap: wrap; }
.post-meta .tags span { color: var(--accent); }

/* Rendered markdown */
.prose { font-size: 1.07rem; line-height: 1.8; color: var(--text); }
.prose > * + * { margin-top: 1.25rem; }
.prose h1, .prose h2, .prose h3, .prose h4 { font-family: var(--font-display); font-weight: 600; line-height: 1.25; letter-spacing: -0.01em; margin-top: 2.4rem; scroll-margin-top: 6rem; }
.prose h2 { font-size: 1.7rem; padding-bottom: 0.4rem; }
.prose h3 { font-size: 1.32rem; }
.prose h4 { font-size: 1.1rem; }
.prose p, .prose li { color: var(--text-muted); }
.prose strong { color: var(--text); font-weight: 600; }
.prose em { color: var(--text); }
.prose a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-color: var(--accent-soft); transition: text-decoration-color 0.2s; }
.prose a:hover { text-decoration-color: var(--accent); }
.prose ul, .prose ol { padding-left: 1.4rem; display: flex; flex-direction: column; gap: 0.5rem; }
.prose ul { list-style: none; padding-left: 0; }
.prose ul > li { position: relative; padding-left: 1.5rem; }
.prose ul > li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); }
.prose ol { list-style: decimal; padding-left: 1.6rem; }
.prose ol > li::marker { color: var(--accent); font-family: var(--font-mono); }
.prose blockquote { border-left: 3px solid var(--accent); padding: 0.6rem 1.3rem; background: var(--accent-soft); border-radius: 0 var(--radius-sm) var(--radius-sm) 0; color: var(--text); font-style: italic; }
.prose blockquote p { color: var(--text); }
.prose img { border-radius: var(--radius-sm); border: 1px solid var(--border); margin-inline: auto; }
.prose hr { border: none; border-top: 1px solid var(--border); margin-block: 2.4rem; }
.prose code { font-family: var(--font-mono); font-size: 0.88em; background: var(--surface-2); padding: 0.18em 0.45em; border-radius: 6px; border: 1px solid var(--border); color: var(--accent); }
.prose pre { background: #0a0e18; border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 1.2rem 1.3rem; overflow-x: auto; position: relative; font-size: 0.9rem; }
[data-theme="light"] .prose pre { background: #0d1424; }
.prose pre code { background: none; border: none; padding: 0; color: #e8eefb; font-size: 0.9rem; }
.code-copy { position: absolute; top: 0.6rem; right: 0.6rem; font-family: var(--font-mono); font-size: 0.7rem; padding: 0.3rem 0.6rem; border-radius: 7px; background: var(--surface-2); border: 1px solid var(--border); color: var(--text-muted); opacity: 0; transition: opacity 0.2s, color 0.2s; }
.prose pre:hover .code-copy { opacity: 1; }
.code-copy:hover { color: var(--accent); border-color: var(--accent); }
.prose table { width: 100%; border-collapse: collapse; font-size: 0.94rem; }
.prose th, .prose td { border: 1px solid var(--border); padding: 0.6rem 0.9rem; text-align: left; }
.prose th { background: var(--surface-2); color: var(--text); font-family: var(--font-display); }
.prose center { display: block; text-align: center; font-family: var(--font-mono); color: var(--accent); background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 0.8rem; }

.post-footer { margin-top: 3rem; padding-top: 2rem; border-top: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem; }
.post-loading { text-align: center; padding: 5rem 1rem; color: var(--text-dim); font-family: var(--font-mono); }
.spinner { width: 34px; height: 34px; border: 3px solid var(--border); border-top-color: var(--accent); border-radius: 50%; margin: 0 auto 1rem; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ==========================================================================
   EFFECTS — aurora bg, particle field, spotlight/tilt cards, reading progress,
   featured post, post cover banner, sticky TOC, back-to-top
   ========================================================================== */

/* Animated background layer behind page heroes */
.fx-bg { position: absolute; inset: 0; overflow: hidden; z-index: -1; pointer-events: none; }
.aurora { position: absolute; inset: -25%; filter: blur(72px); opacity: 0.6; }
.aurora span { position: absolute; display: block; border-radius: 50%; mix-blend-mode: screen; animation: drift 20s ease-in-out infinite; }
.aurora span:nth-child(1) { width: 46vw; height: 46vw; left: -4%; top: -12%; background: radial-gradient(circle, rgba(34,211,238,0.55), transparent 65%); }
.aurora span:nth-child(2) { width: 42vw; height: 42vw; right: -8%; top: -6%; background: radial-gradient(circle, rgba(99,102,241,0.5), transparent 65%); animation-delay: -7s; }
.aurora span:nth-child(3) { width: 38vw; height: 38vw; left: 32%; bottom: -20%; background: radial-gradient(circle, rgba(56,189,248,0.45), transparent 65%); animation-delay: -13s; }
[data-theme="light"] .aurora { opacity: 0.42; }
@keyframes drift {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33%      { transform: translate(6%, 4%) scale(1.12); }
  66%      { transform: translate(-5%, -3%) scale(0.94); }
}
canvas[data-particles] { position: absolute; inset: 0; width: 100%; height: 100%; z-index: -1; pointer-events: none; opacity: 0; transition: opacity 1.2s var(--ease); }
canvas[data-particles].ready { opacity: 1; }

/* Floating parallax depth layers */
.p-field { position: absolute; inset: 0; z-index: -1; pointer-events: none; overflow: hidden; }
.shard { position: absolute; opacity: 0.5; }
.shard--dot { border-radius: 50%; background: radial-gradient(circle at 32% 30%, var(--accent), transparent 70%); filter: blur(1px); opacity: 0.4; }
.shard--ring { border-radius: 50%; border: 1.5px solid var(--accent); opacity: 0.22; }
.shard--sq { border: 1.5px solid var(--accent-3); border-radius: 7px; opacity: 0.2; }
[data-theme="light"] .shard { opacity: 0.3; }

/* Page hero → richer animated band */
.page-hero { position: relative; overflow: hidden; }
.page-hero .container { position: relative; z-index: 1; }
.page-hero::after { content: ""; position: absolute; inset: auto 0 0 0; height: 46%; background: linear-gradient(to top, var(--bg), transparent); z-index: 0; }

/* Cursor-spotlight + 3D tilt cards */
.fx-card { position: relative; transform-style: preserve-3d; transition: transform 0.18s var(--ease), border-color 0.3s, box-shadow 0.3s; will-change: transform; }
.fx-card::before { content: ""; position: absolute; inset: 0; border-radius: inherit; opacity: 0; transition: opacity 0.35s; background: radial-gradient(440px circle at var(--mx, 50%) var(--my, 50%), var(--accent-soft), transparent 46%); pointer-events: none; z-index: 0; }
.fx-card:hover::before { opacity: 1; }
.fx-card > * { position: relative; z-index: 1; }

/* Reading progress bar */
.reading-progress { position: fixed; top: 0; left: 0; right: 0; height: 3px; z-index: 200; background: transparent; pointer-events: none; }
.reading-progress span { display: block; height: 100%; width: 0; background: var(--gradient); box-shadow: 0 0 12px var(--accent-glow); }

/* Floating back-to-top */
#backToTop { position: fixed; right: 1.4rem; bottom: 1.4rem; width: 48px; height: 48px; border-radius: 50%; display: grid; place-items: center; background: var(--surface-2); border: 1px solid var(--border-strong); backdrop-filter: blur(10px); color: var(--text); z-index: 150; opacity: 0; visibility: hidden; transform: translateY(14px) scale(0.9); transition: opacity 0.35s var(--ease), transform 0.35s var(--ease), visibility 0.35s, color 0.25s, border-color 0.25s; box-shadow: var(--shadow); }
#backToTop.show { opacity: 1; visibility: visible; transform: none; }
#backToTop:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-3px); }
#backToTop svg { width: 20px; height: 20px; }

/* Featured post (blog) */
.featured { margin-bottom: 2.2rem; }
.featured-card { position: relative; display: grid; grid-template-columns: 1.05fr 1fr; gap: 0; border-radius: var(--radius-lg); overflow: hidden; min-height: 320px; }
.featured-card__art { position: relative; overflow: hidden; min-height: 230px; }
.featured-card__art .glow { position: absolute; inset: 0; background: var(--feat-grad, var(--gradient)); }
.featured-card__art .grid-lines { position: absolute; inset: 0; background-image: linear-gradient(rgba(255,255,255,0.10) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.10) 1px, transparent 1px); background-size: 32px 32px; -webkit-mask-image: radial-gradient(circle at 50% 50%, #000, transparent 74%); mask-image: radial-gradient(circle at 50% 50%, #000, transparent 74%); }
.featured-card__art .badge { position: absolute; top: 1.1rem; left: 1.1rem; font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; background: rgba(4,16,24,0.55); color: #fff; padding: 0.34rem 0.72rem; border-radius: 999px; backdrop-filter: blur(6px); }
.featured-card__body { padding: clamp(1.6rem, 3vw, 2.6rem); display: flex; flex-direction: column; justify-content: center; gap: 0.7rem; }
.featured-card__body .date { font-family: var(--font-mono); font-size: 0.78rem; color: var(--text-dim); }
.featured-card__body h2 { font-family: var(--font-display); font-weight: 600; font-size: clamp(1.5rem, 1.1rem + 1.6vw, 2.2rem); line-height: 1.12; letter-spacing: -0.02em; }
.featured-card__body p { color: var(--text-muted); }
.featured-card__body .tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: 0.2rem; }
@media (max-width: 760px) { .featured-card { grid-template-columns: 1fr; } .featured-card__art { min-height: 150px; } }

/* Post cover banner */
.post-cover { position: relative; overflow: hidden; padding: 8.5rem 0 2.4rem; margin-bottom: 2.4rem; }
.post-cover::before { content: ""; position: absolute; inset: 0; background: var(--cover-grad, var(--gradient)); opacity: 0.16; z-index: -1; }
.post-cover::after { content: ""; position: absolute; inset: auto 0 0 0; height: 60%; background: linear-gradient(to top, var(--bg), transparent); z-index: -1; }
.post-cover .container { position: relative; z-index: 1; max-width: 820px; }
.post-cover .post-back { margin-bottom: 1.3rem; }
.post-cover__tags { display: flex; flex-wrap: wrap; gap: 0.45rem; margin-bottom: 1rem; }
.post-cover__tags span { font-family: var(--font-mono); font-size: 0.72rem; padding: 0.3rem 0.7rem; border-radius: 999px; background: var(--surface-2); border: 1px solid var(--border); color: var(--accent); }
.post-cover h1 { font-family: var(--font-display); font-weight: 600; font-size: clamp(2rem, 1.4rem + 3vw, 3.3rem); line-height: 1.08; letter-spacing: -0.02em; margin-bottom: 1rem; }

/* Post layout with sticky TOC (desktop) */
.post-layout { display: grid; grid-template-columns: 1fr; gap: 2rem; }
.post-toc { display: none; }
@media (min-width: 1080px) {
  .post-layout { grid-template-columns: minmax(0, 1fr) 220px; align-items: start; }
  .post-toc { display: block; position: sticky; top: 6.5rem; order: 2; font-size: 0.88rem; border-left: 1px solid var(--border); padding-left: 1.1rem; max-height: 80vh; overflow: auto; }
  .post-wrap { order: 1; padding-top: 0; max-width: none; }
  .post-layout.no-toc { grid-template-columns: 1fr; }
  .post-layout.no-toc .post-wrap { max-width: 760px; margin-inline: auto; }
}
.post-toc__title { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-dim); margin-bottom: 0.8rem; }
.post-toc a { display: block; padding: 0.32rem 0 0.32rem 1.1rem; margin-left: -1.1rem; color: var(--text-muted); border-left: 2px solid transparent; transition: color 0.2s, border-color 0.2s; line-height: 1.35; }
.post-toc a.lvl-3 { padding-left: 2rem; font-size: 0.83rem; }
.post-toc a:hover { color: var(--text); }
.post-toc a.active { color: var(--accent); border-left-color: var(--accent); }

/* ==========================================================================
   REDUCED MOTION
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
  .reveal { opacity: 1; transform: none; }
  [data-parallax] { transform: none !important; }
  .fx-card { transform: none !important; }
  .aurora span { animation: none !important; }
}