/* ============================================================
   Hanz Joseph Canda — AI Engineering Portfolio
   Dark-first, responsive, dependency-free stylesheet.
   ============================================================ */

/* ---------- Tokens ---------- */
:root {
  --bg: #0a0e14;
  --bg-soft: #0f1520;
  --surface: #131b29;
  --surface-2: #182234;
  --border: #232f47;
  --border-soft: #1b2536;
  --text: #e8edf5;
  --muted: #9aa7bd;
  --faint: #6b7a93;
  --accent: #38bdf8;
  --accent-2: #818cf8;
  --accent-3: #22d3ee;
  --accent-ink: #06263a;
  --success: #34d399;
  --warning: #fbbf24;
  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 18px 50px -18px rgba(2, 8, 20, 0.8);
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI",
    Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
  --max: 1120px;
  --header-h: 64px;
}

[data-theme="light"] {
  --bg: #f6f8fc;
  --bg-soft: #ffffff;
  --surface: #ffffff;
  --surface-2: #eef2f9;
  --border: #d7e0ee;
  --border-soft: #e5ebf5;
  --text: #101828;
  --muted: #475569;
  --faint: #7c8aa0;
  --accent: #0284c7;
  --accent-2: #4f46e5;
  --accent-3: #0891b2;
  --accent-ink: #ffffff;
  --shadow: 0 18px 45px -22px rgba(15, 40, 80, 0.25);
  color-scheme: light;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  font-family: var(--font);
  background:
    radial-gradient(900px 420px at 85% -80px, rgba(56, 189, 248, 0.09), transparent 60%),
    radial-gradient(760px 380px at 8% 4%, rgba(129, 140, 248, 0.08), transparent 60%),
    var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.25s ease, color 0.25s ease;
}

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

h1, h2, h3 { line-height: 1.18; letter-spacing: -0.02em; margin: 0 0 0.6rem; }
h1 { font-size: clamp(2rem, 4.6vw, 3.3rem); font-weight: 800; }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); font-weight: 750; }
h3 { font-size: 1.05rem; font-weight: 650; }

p { margin: 0 0 1rem; }
a { color: var(--accent); }
a:hover { color: var(--accent-3); }

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.container { width: min(var(--max), 100% - 2.5rem); margin-inline: auto; }
.container.narrow { max-width: 780px; }

.section { padding: clamp(3.5rem, 7vw, 5.5rem) 0; }
.section-alt { background: var(--bg-soft); border-block: 1px solid var(--border-soft); }

.eyebrow {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid var(--border);
  background: var(--surface);
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  margin-bottom: 1rem;
}

.section-sub { color: var(--muted); max-width: 62ch; }
.lede { font-size: clamp(1.02rem, 1.6vw, 1.18rem); color: var(--muted); }
.prose p { color: var(--muted); }
.prose strong { color: var(--text); }

.gradient-text {
  background: linear-gradient(92deg, var(--accent) 10%, var(--accent-2) 55%, var(--accent-3) 95%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 200;
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 700;
  padding: 0.6rem 1rem;
  border-radius: 8px;
  text-decoration: none;
  transition: top 0.2s ease;
}
.skip-link:focus { top: 0.75rem; }

/* ---------- Header / nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-soft);
}

.nav { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: var(--text);
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 11px;
  font-weight: 800;
  font-size: 0.85rem;
  color: #fff;
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  box-shadow: var(--shadow);
}
.brand-text { font-weight: 750; font-size: 0.98rem; line-height: 1.1; display: flex; flex-direction: column; }
.brand-sub { font-size: 0.68rem; font-weight: 600; letter-spacing: 0.12em; text-transform: uppercase; color: var(--faint); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-link {
  display: block;
  padding: 0.55rem 0.8rem;
  border-radius: 8px;
  text-decoration: none;
  color: var(--muted);
  font-weight: 600;
  font-size: 0.93rem;
}
.nav-link:hover { color: var(--text); background: var(--surface); }
.nav-link.active { color: var(--text); background: var(--surface); box-shadow: inset 0 0 0 1px var(--border); }

.nav-actions { display: flex; align-items: center; gap: 0.6rem; margin-left: 0.5rem; }

.theme-toggle {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
  cursor: pointer;
}
.theme-toggle:hover { color: var(--text); border-color: var(--accent); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.65rem 0.7rem;
  cursor: pointer;
}
.nav-toggle span { display: block; width: 20px; height: 2px; background: var(--text); border-radius: 2px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 0.95rem;
  padding: 0.75rem 1.35rem;
  border-radius: 11px;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}
.btn-primary {
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  color: #fff;
  box-shadow: 0 10px 28px -10px rgba(56, 130, 248, 0.55);
}
.btn-primary:hover { color: #fff; transform: translateY(-1px); box-shadow: 0 14px 32px -10px rgba(56, 130, 248, 0.65); }
.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border);
}
.btn-secondary:hover { color: var(--text); border-color: var(--accent); transform: translateY(-1px); }
.btn-sm { padding: 0.55rem 1rem; font-size: 0.88rem; }

/* ---------- Hero ---------- */
.hero { padding: clamp(2.5rem, 6vw, 4.5rem) 0 clamp(3rem, 6vw, 4.5rem); }
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}

.availability {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.82rem;
  font-weight: 650;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.42rem 0.95rem;
  margin-bottom: 1.25rem;
}
.pulse-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--success); box-shadow: 0 0 0 4px color-mix(in srgb, var(--success) 22%, transparent); }

.hero-cta { display: flex; flex-wrap: wrap; align-items: center; gap: 0.8rem; margin: 1.6rem 0; }

.github-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--muted);
  font-weight: 700;
  text-decoration: none;
  padding: 0.7rem 0.9rem;
  border-radius: 11px;
  border: 1px solid transparent;
}
.github-link:hover { color: var(--text); border-color: var(--border); background: var(--surface); }

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin: 1.5rem 0 0;
  padding: 1rem 0 0;
  border-top: 1px solid var(--border-soft);
}
.hero-meta div { margin: 0; }
.hero-meta dt { font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--faint); font-weight: 700; }
.hero-meta dd { margin: 0.15rem 0 0; font-weight: 650; font-size: 0.92rem; }

/* ---------- Photo ---------- */
.hero-photo { display: flex; justify-content: center; }
.photo-frame {
  margin: 0;
  position: relative;
  width: min(330px, 100%);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 0.7rem 0.7rem 0;
  box-shadow: var(--shadow);
}
.photo-frame::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: 21px;
  padding: 1px;
  background: linear-gradient(140deg, rgba(56, 189, 248, 0.5), transparent 35%, transparent 65%, rgba(129, 140, 248, 0.5));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}
.photo-frame img {
  width: 100%;
  aspect-ratio: 4 / 4.6;
  object-fit: cover;
  object-position: top center;
  border-radius: 13px;
  background: var(--surface-2);
}
.photo-caption {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  padding: 0.85rem 0.4rem 1rem;
}
.photo-caption strong { font-size: 1rem; }
.photo-caption span { font-size: 0.82rem; color: var(--muted); }

/* ---------- About ---------- */
.about-highlights {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.9rem;
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
}
.about-highlights li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}
.about-highlights strong { font-size: 1.6rem; font-weight: 800; color: var(--accent); }
.about-highlights span { font-size: 0.85rem; color: var(--muted); }

/* ---------- Skills ---------- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 2rem;
}
.skill-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem 1.25rem;
  transition: transform 0.18s ease, border-color 0.2s ease;
}
.skill-card:hover { transform: translateY(-3px); border-color: color-mix(in srgb, var(--accent) 55%, var(--border)); }
.skill-card h3 { font-size: 0.95rem; margin-bottom: 0.9rem; color: var(--text); }

.tag-list { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 0.45rem; }
.tag-list li {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.83rem;
  font-weight: 600;
  color: var(--muted);
  background: var(--surface-2);
  border: 1px solid var(--border-soft);
  border-radius: 999px;
  padding: 0.32rem 0.7rem 0.32rem 0.4rem;
}
.pill {
  font-size: 0.62rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-radius: 999px;
  padding: 0.12rem 0.45rem;
  white-space: nowrap;
}
.pill-verified { background: rgba(52, 211, 153, 0.14); color: var(--success); border: 1px solid rgba(52, 211, 153, 0.35); }
.pill-learning { background: rgba(251, 191, 36, 0.12); color: var(--warning); border: 1px solid rgba(251, 191, 36, 0.35); }

/* ---------- Filters + projects ---------- */
.filters { display: flex; flex-wrap: wrap; gap: 0.55rem; margin: 1.75rem 0 0.5rem; }
.filter-btn {
  font: inherit;
  font-size: 0.87rem;
  font-weight: 700;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.5rem 1.1rem;
  cursor: pointer;
  transition: all 0.18s ease;
}
.filter-btn:hover { color: var(--text); border-color: var(--accent); }
.filter-btn[aria-pressed="true"] {
  color: #fff;
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  border-color: transparent;
}
.filter-status { font-size: 0.85rem; color: var(--faint); min-height: 1.4em; margin: 0 0 1rem; }

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.1rem;
}
.project-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.4rem 1.3rem;
  position: relative;
  overflow: hidden;
  transition: transform 0.18s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}
.project-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  opacity: 0.9;
}
.project-card.accent-cyan::before { background: linear-gradient(90deg, var(--accent-3), var(--accent)); }
.project-card.accent-violet::before { background: linear-gradient(90deg, var(--accent-2), #a78bfa); }
.project-card:hover { transform: translateY(-4px); border-color: color-mix(in srgb, var(--accent) 50%, var(--border)); box-shadow: var(--shadow); }

.project-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 0.75rem; margin-bottom: 0.7rem; }
.project-icon {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--accent);
  flex-shrink: 0;
}
.status-badge {
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.22rem 0.65rem;
  white-space: nowrap;
}
.project-card h3 { font-size: 1.15rem; margin-bottom: 0.3rem; }
.project-tagline { font-size: 0.92rem; font-weight: 600; color: var(--text); margin-bottom: 0.6rem; }
.project-card p { font-size: 0.88rem; color: var(--muted); }
.project-label { font-size: 0.7rem; font-weight: 800; letter-spacing: 0.1em; text-transform: uppercase; color: var(--faint); margin: 0.9rem 0 0.4rem; }
.project-features { margin: 0; padding-left: 1.1rem; font-size: 0.85rem; color: var(--muted); }
.project-features li { margin-bottom: 0.3rem; }
.project-features li::marker { color: var(--accent); }
.stack-list { display: flex; flex-wrap: wrap; gap: 0.4rem; list-style: none; margin: 0; padding: 0; }
.stack-list li {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--muted);
  background: var(--surface-2);
  border: 1px solid var(--border-soft);
  border-radius: 7px;
  padding: 0.18rem 0.5rem;
}
.eng-list { margin: 0; padding-left: 1.1rem; font-size: 0.82rem; color: var(--faint); }
.eng-list li { margin-bottom: 0.2rem; }

.project-link {
  margin-top: auto;
  padding-top: 1.1rem;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-weight: 750;
  font-size: 0.9rem;
  text-decoration: none;
}
.project-link:hover { text-decoration: underline; }

.noscript-note { color: var(--muted); }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- Principles ---------- */
.principles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 2rem;
}
.principle-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem 1.25rem;
}
.principle-card h3 { display: flex; align-items: center; gap: 0.6rem; }
.principle-icon { color: var(--accent); font-size: 1.1rem; }
.principle-card p { font-size: 0.9rem; color: var(--muted); margin: 0; }

/* ---------- Growth ---------- */
.growth-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
  list-style: none;
  margin: 1.75rem 0;
  padding: 0;
}
.growth-list li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.7rem 0.95rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--muted);
}
.growth-list li::before { content: "→"; color: var(--accent); font-weight: 800; }
.prose-note { color: var(--muted); border-left: 3px solid var(--accent); padding-left: 1rem; font-size: 0.95rem; }

/* ---------- Contact ---------- */
.contact-box { text-align: center; }
.contact-box .lede { margin-inline: auto; max-width: 58ch; }
.contact-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.9rem;
  margin: 2rem 0 1.5rem;
  text-align: left;
}
.contact-card {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.15rem 1.25rem;
  text-decoration: none;
  transition: border-color 0.2s ease, transform 0.18s ease;
  overflow-wrap: anywhere;
}
.contact-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.contact-label { font-size: 0.72rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; color: var(--faint); }
.contact-value { font-weight: 750; color: var(--text); font-size: 1rem; }
.contact-cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 0.8rem; }
.copy-feedback { min-height: 1.5em; font-size: 0.88rem; color: var(--success); font-weight: 650; margin-top: 0.9rem; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--border-soft); padding: 1.75rem 0; background: var(--bg-soft); }
.footer-grid { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.75rem; }
.site-footer p { margin: 0; font-size: 0.86rem; color: var(--faint); }
.footer-links a { color: var(--muted); text-decoration: none; font-weight: 600; }
.footer-links a:hover { color: var(--text); }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity 0.55s ease, transform 0.55s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-photo { order: -1; }
  .photo-frame { width: min(260px, 80%); }
  .project-grid { grid-template-columns: repeat(2, 1fr); }
  .skills-grid { grid-template-columns: repeat(2, 1fr); }
  .principles-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0.15rem;
    background: var(--bg-soft);
    border-bottom: 1px solid var(--border);
    padding: 0.75rem 1.25rem 1rem;
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-link { padding: 0.7rem 0.8rem; }
  .nav-actions { margin: 0.4rem 0 0; justify-content: flex-start; }
  .project-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr; }
  .principles-grid { grid-template-columns: 1fr; }
  .growth-list { grid-template-columns: 1fr; }
  .contact-cards { grid-template-columns: 1fr; }
  .about-highlights { grid-template-columns: 1fr; }
}

/* ---------- 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; }
  .pulse-dot { box-shadow: none; }
}