/* ==========================================================================
   Daniel Irwin — developer resume site
   Vanilla CSS, no build step. Palette inspired by GitHub's "dark dimmed"
   theme (a lighter dark theme) with a light-mode override.
   ========================================================================== */

/* ---------- Design tokens ---------- */
:root {
  --bg: #22272e;
  --bg-elevated: #2d333b;
  --bg-elevated-2: #373e47;
  --border: #444c56;
  --border-soft: #373e47;
  --text: #adbac7;
  --text-bright: #cdd9e5;
  --text-dim: #768390;
  --accent: #6cb6ff;
  --accent-strong: #539bf5;
  --accent-2: #b083f0;
  --accent-3: #57ab5a;
  --accent-warm: #e2a03f;
  --shadow: 0 20px 45px -18px rgba(0, 0, 0, 0.55);
  --shadow-sm: 0 8px 20px -10px rgba(0, 0, 0, 0.5);
  --radius: 14px;
  --radius-sm: 8px;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --nav-h: 72px;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

html[data-theme="light"] {
  --bg: #ffffff;
  --bg-elevated: #f6f8fa;
  --bg-elevated-2: #eaeef2;
  --border: #d1d9e0;
  --border-soft: #e7ebef;
  --text: #3b434b;
  --text-bright: #1f2328;
  --text-dim: #6b7280;
  --accent: #0969da;
  --accent-strong: #0550ae;
  --accent-2: #8250df;
  --accent-3: #1a7f37;
  --accent-warm: #9a6700;
  --shadow: 0 20px 45px -20px rgba(31, 35, 40, 0.18);
  --shadow-sm: 0 8px 20px -12px rgba(31, 35, 40, 0.16);
}

* , *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-h);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  transition: background-color 0.4s var(--ease), color 0.4s var(--ease);
}

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

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 8px; border: 2px solid var(--bg); }
::-webkit-scrollbar-thumb:hover { background: var(--text-dim); }

img { max-width: 100%; display: block; }

a { color: inherit; text-decoration: none; }

h1, h2, h3 {
  font-family: var(--font-mono);
  color: var(--text-bright);
  font-weight: 700;
  line-height: 1.2;
  margin: 0;
}

p { margin: 0 0 1em; color: var(--text); }
p:last-child { margin-bottom: 0; }

.accent { color: var(--accent); }

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--accent-strong);
  color: #fff;
  padding: 10px 16px;
  border-radius: 0 0 8px 0;
  z-index: 999;
}
.skip-link:focus { left: 0; }

/* ---------- Background layers ---------- */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -2;
  background-image:
    linear-gradient(var(--border-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--border-soft) 1px, transparent 1px);
  background-size: 56px 56px;
  opacity: 0.35;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 40%, transparent 90%);
}
html[data-theme="light"] .bg-grid { opacity: 0.5; }

.bg-glow {
  position: fixed;
  inset: 0;
  z-index: -3;
  background:
    radial-gradient(600px circle at 15% 10%, rgba(84, 174, 255, 0.15), transparent 60%),
    radial-gradient(500px circle at 85% 30%, rgba(176, 131, 240, 0.12), transparent 60%);
}

/* ---------- Scroll progress ---------- */
.scroll-progress {
  position: fixed;
  top: 0; left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--accent-strong), var(--accent-2));
  z-index: 1000;
  transition: width 0.1s linear;
}

/* ---------- Nav ---------- */
.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 500;
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background-color 0.3s var(--ease), height 0.3s var(--ease);
}
.site-nav.scrolled {
  border-bottom-color: var(--border-soft);
  height: 62px;
}

.nav-inner {
  max-width: 1180px;
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text-bright);
  white-space: nowrap;
}
.brand-bracket { color: var(--text-dim); }

.nav-links {
  display: flex;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.nav-link {
  position: relative;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: var(--text);
  transition: color 0.2s var(--ease), background-color 0.2s var(--ease);
}
.nav-index { color: var(--accent); margin-right: 4px; font-weight: 600; }
.nav-link:hover { color: var(--text-bright); background: var(--bg-elevated); }
.nav-link.active { color: var(--accent); }
.nav-link.active::after {
  content: "";
  position: absolute;
  left: 12px; right: 12px; bottom: 3px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
}

.nav-actions { display: flex; align-items: center; gap: 10px; }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px; height: 38px;
  border-radius: 50%;
  border: 1px solid var(--border-soft);
  background: var(--bg-elevated);
  color: var(--text);
  cursor: pointer;
  transition: transform 0.25s var(--ease), color 0.25s var(--ease), border-color 0.25s var(--ease);
}
.icon-btn svg { width: 18px; height: 18px; }
.icon-btn:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px) rotate(8deg); }

.icon-moon { display: none; }
html[data-theme="light"] .icon-sun { display: none; }
html[data-theme="light"] .icon-moon { display: block; }

.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 38px; height: 38px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-soft);
  background: var(--bg-elevated);
  cursor: pointer;
}
.hamburger span {
  display: block;
  width: 18px; height: 2px;
  margin: 0 auto;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.9rem;
  padding: 12px 22px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), background-color 0.25s var(--ease), border-color 0.25s var(--ease), color 0.25s var(--ease);
}
.btn svg { width: 16px; height: 16px; }
.btn:active { transform: translateY(1px) scale(0.98); }

.btn-primary {
  background: linear-gradient(135deg, var(--accent-strong), var(--accent-2));
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { transform: translateY(-3px); box-shadow: var(--shadow); }

.btn-ghost {
  background: transparent;
  border-color: var(--border);
  color: var(--text-bright);
}
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-3px); }

.btn-sm { padding: 8px 14px; font-size: 0.78rem; }
.btn-lg { padding: 15px 28px; font-size: 0.95rem; }
.nav-cta { display: inline-flex; }

/* ---------- Layout helpers ---------- */
.section { padding: 128px 24px; position: relative; }
.section-alt { background: color-mix(in srgb, var(--bg-elevated) 55%, transparent); }
.section-inner { max-width: 1180px; margin: 0 auto; }
.section-cta { text-align: center; }

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 12px;
}
.section-title.center { justify-content: center; }
.title-index { color: var(--accent); font-size: 0.55em; }

.section-sub {
  color: var(--text-dim);
  max-width: 640px;
  margin-bottom: 48px;
  font-size: 1.02rem;
}
.section-title.center + .contact-sub { margin: 0 auto 40px; text-align: center; }

/* ---------- Reveal-on-scroll ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.reveal.in-view { opacity: 1; transform: translateY(0); }

/* ---------- Hero ---------- */
.hero {
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: calc(var(--nav-h) + 40px) 24px 80px;
  overflow: hidden;
}

.hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  opacity: 0.55;
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 780px;
  text-align: center;
}

.eyebrow {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.95rem;
  margin-bottom: 14px;
  transition-delay: 0.05s;
}

.hero-name {
  font-size: clamp(2.6rem, 8vw, 5rem);
  background: linear-gradient(135deg, var(--text-bright), var(--accent) 55%, var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 18px;
  transition-delay: 0.1s;
}

.hero-role {
  font-family: var(--font-mono);
  font-size: clamp(1.1rem, 2.6vw, 1.5rem);
  color: var(--text-bright);
  min-height: 1.6em;
  margin-bottom: 22px;
  transition-delay: 0.15s;
}
.cursor {
  display: inline-block;
  width: 2px;
  height: 1em;
  background: var(--accent);
  margin-left: 3px;
  vertical-align: -0.15em;
  animation: blink 1s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }

.hero-tagline {
  font-size: 1.1rem;
  color: var(--text-dim);
  max-width: 620px;
  margin: 0 auto 34px;
  transition-delay: 0.2s;
}

.hero-ctas {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 34px;
  transition-delay: 0.25s;
}

.hero-tags {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  transition-delay: 0.3s;
}
.tag-chip {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-dim);
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  padding: 6px 12px;
  border-radius: 999px;
}

.scroll-cue {
  position: absolute;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  width: 34px; height: 34px;
  border-radius: 50%;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  animation: bob 2.2s ease-in-out infinite;
  z-index: 1;
}
.scroll-cue svg { width: 16px; height: 16px; }
.scroll-cue:hover { color: var(--accent); border-color: var(--accent); }
@keyframes bob {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 56px;
  align-items: start;
}

.about-photo-frame {
  position: relative;
  border-radius: var(--radius);
  padding: 6px;
  background: linear-gradient(135deg, var(--accent-strong), var(--accent-2));
  transition: transform 0.4s var(--ease);
}
.about-photo-wrap:hover .about-photo-frame { transform: rotate(-2deg) scale(1.02); }
.about-photo {
  border-radius: 10px;
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  background: var(--bg-elevated);
}

.about-text h3 {
  font-size: 1rem;
  color: var(--accent);
  margin: 28px 0 10px;
}
.about-text h3:first-child { margin-top: 0; }

/* ---------- Grids / cards ---------- */
.grid {
  display: grid;
  gap: 22px;
}
.work-grid { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.os-grid { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }

.card {
  position: relative;
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  padding: 26px;
  overflow: hidden;
  transition: transform 0.35s var(--ease), border-color 0.35s var(--ease), box-shadow 0.35s var(--ease);
}
.card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-strong), var(--accent-2));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s var(--ease);
}
.card:hover {
  transform: translateY(-6px);
  border-color: var(--border);
  box-shadow: var(--shadow);
}
.card:hover::before { transform: scaleX(1); }

.card-title {
  font-family: var(--font-mono);
  color: var(--text-bright);
  font-size: 1.05rem;
  margin-bottom: 10px;
}

.card-desc {
  color: var(--text-dim);
  font-size: 0.94rem;
  margin-bottom: 16px;
}

.tag-row { display: flex; flex-wrap: wrap; gap: 8px; }
.tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
  padding: 4px 9px;
  border-radius: 999px;
}

.os-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 10px;
}
.os-name {
  font-family: var(--font-mono);
  color: var(--text-bright);
  font-size: 0.98rem;
  word-break: break-word;
}
.os-link {
  display: inline-flex;
  color: var(--text-dim);
  transition: color 0.25s var(--ease), transform 0.25s var(--ease);
  flex-shrink: 0;
}
.os-link svg { width: 16px; height: 16px; }
.os-card:hover .os-link { color: var(--accent); transform: translate(2px, -2px); }
.os-badge { height: 18px; opacity: 0.9; }

/* ---------- Skills ---------- */
.skills-groups {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 26px;
}
.skill-group {
  background: var(--bg-elevated);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  padding: 22px 24px;
}
.skill-group-label {
  font-family: var(--font-mono);
  color: var(--accent);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 14px;
}
.skill-pills { display: flex; flex-wrap: wrap; gap: 8px; }
.skill-pill {
  font-size: 0.85rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border-soft);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  transition: transform 0.25s var(--ease), color 0.25s var(--ease), border-color 0.25s var(--ease), background-color 0.25s var(--ease);
}
.skill-pill:hover {
  color: var(--accent);
  border-color: var(--accent);
  transform: translateY(-3px);
  background: color-mix(in srgb, var(--accent) 10%, var(--bg));
}

/* ---------- Legos ---------- */
.lego-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 18px;
}
.lego-item {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  aspect-ratio: 4 / 3;
  cursor: zoom-in;
  border: 1px solid var(--border-soft);
  background: var(--bg-elevated);
}
.lego-item img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.5s var(--ease), filter 0.5s var(--ease);
}
.lego-caption {
  position: absolute;
  inset: auto 0 0 0;
  padding: 28px 14px 12px;
  background: linear-gradient(to top, rgba(0,0,0,0.78), transparent);
  color: #fff;
  font-size: 0.82rem;
  font-family: var(--font-mono);
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.35s var(--ease), transform 0.35s var(--ease);
}
.lego-item:hover img { transform: scale(1.08); }
.lego-item:hover .lego-caption { opacity: 1; transform: translateY(0); }
.lego-item:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Contact ---------- */
.contact-inner { max-width: 640px; margin: 0 auto; }
.contact-sub { color: var(--text-dim); margin-bottom: 36px; font-size: 1.05rem; }
.contact-ctas { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border-soft);
  padding: 28px 24px;
}
.footer-inner {
  max-width: 1180px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  color: var(--text-dim);
  font-size: 0.85rem;
}

#backToTop {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 400;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s var(--ease), visibility 0.3s var(--ease), transform 0.3s var(--ease);
}
#backToTop.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
#backToTop.show:hover {
  transform: translateY(-2px) rotate(8deg);
}

/* ---------- Lightbox ---------- */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(10, 12, 16, 0.88);
  backdrop-filter: blur(6px);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s var(--ease), visibility 0.3s var(--ease);
  padding: 24px;
}
.lightbox.open { opacity: 1; visibility: visible; }
.lightbox-figure {
  max-width: min(920px, 90vw);
  max-height: 86vh;
  margin: 0;
  transform: scale(0.94);
  transition: transform 0.35s var(--ease);
}
.lightbox.open .lightbox-figure { transform: scale(1); }
.lightbox-figure img {
  max-height: 76vh;
  border-radius: 10px;
  margin: 0 auto;
  box-shadow: 0 30px 60px -20px rgba(0,0,0,0.6);
}
.lightbox-figure figcaption {
  text-align: center;
  color: #cdd9e5;
  font-family: var(--font-mono);
  margin-top: 16px;
  font-size: 0.9rem;
}
.lightbox-btn {
  position: absolute;
  width: 44px; height: 44px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.25);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background-color 0.25s var(--ease), transform 0.25s var(--ease);
}
.lightbox-btn svg { width: 20px; height: 20px; }
.lightbox-btn:hover { background: rgba(255,255,255,0.18); transform: scale(1.08); }
.lightbox-close { top: 20px; right: 20px; }
.lightbox-prev { left: 20px; top: 50%; transform: translateY(-50%); }
.lightbox-next { right: 20px; top: 50%; transform: translateY(-50%); }

/* ---------- Toast ---------- */
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translate(-50%, 20px);
  background: var(--bg-elevated-2);
  border: 1px solid var(--border);
  color: var(--text-bright);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  padding: 12px 18px;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease);
  z-index: 950;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    flex-direction: column;
    background: var(--bg);
    border-bottom: 1px solid var(--border-soft);
    padding: 10px 20px 20px;
    gap: 2px;
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), visibility 0.3s var(--ease);
  }
  .nav-links.open {
    opacity: 1;
    transform: translateY(0);
    visibility: visible;
  }
  .nav-link { padding: 12px 8px; font-size: 0.95rem; }
  .hamburger { display: flex; }
  .nav-cta { display: none; }
  .about-grid { grid-template-columns: 1fr; }
  .about-photo-frame { max-width: 220px; margin: 0 auto; }
}

@media (max-width: 560px) {
  .section { padding: 88px 18px; }
  .hero { padding-top: calc(var(--nav-h) + 24px); }
  .footer-inner { flex-direction: column; text-align: center; }
}

@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;
    scroll-behavior: auto !important;
  }
}