/* ============================================================
   Mateusz Worotyński — Fractional CTO & Technology Advisor
   Design system: CSS custom properties, light + dark themes
   ============================================================ */

:root {
  --font-display: "Instrument Serif", Georgia, serif;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  --bg: #ffffff;
  --bg-alt: #f7f7f6;
  --surface: #ffffff;
  --text: #111111;
  --text-muted: #5f5f5b;
  --text-faint: #8f8f8a;
  --border: #e8e7e3;
  --border-strong: #d9d8d2;
  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-soft: rgba(79, 70, 229, 0.08);
  --shadow: 0 1px 2px rgba(17, 17, 17, 0.04), 0 8px 24px rgba(17, 17, 17, 0.06);

  --radius: 12px;
  --radius-sm: 8px;
  --container: 1080px;
  --gutter: 24px;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

html[data-theme="dark"] {
  --bg: #0c0c0d;
  --bg-alt: #121213;
  --surface: #141416;
  --text: #ededec;
  --text-muted: #a0a09b;
  --text-faint: #6d6d68;
  --border: #242426;
  --border-strong: #333336;
  --accent: #7c83f8;
  --accent-hover: #9399ff;
  --accent-soft: rgba(124, 131, 248, 0.12);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 12px 32px rgba(0, 0, 0, 0.4);
}

/* ---------- Reset & base ---------- */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--transition), color var(--transition);
}

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

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

ul {
  list-style: none;
}

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

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

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------- Typography helpers ---------- */

.eyebrow {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.section-kicker {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
  max-width: 22ch;
}

.section-title em {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
}

.section-lede {
  margin-top: 1.25rem;
  color: var(--text-muted);
  max-width: 56ch;
  font-size: 1.0625rem;
}

.section-head {
  margin-bottom: 3rem;
}

/* ---------- Header / nav ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: 68px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: var(--text);
  color: var(--bg);
  font-family: var(--font-display);
  font-style: italic;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
}

html[data-theme="dark"] .brand-mark {
  background: var(--text);
  color: var(--bg);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  font-size: 0.925rem;
  color: var(--text-muted);
}

.nav-links a {
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--text);
}

.nav-cta {
  font-weight: 600;
  color: var(--text) !important;
}

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

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

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--border-strong);
}

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

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 38px;
  height: 38px;
  padding: 9px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  height: 1.5px;
  background: var(--text);
  border-radius: 2px;
  transition: transform var(--transition);
}

.menu-toggle[aria-expanded="true"] span:first-child {
  transform: translateY(3.25px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:last-child {
  transform: translateY(-3.25px) rotate(-45deg);
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.5rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1;
  cursor: pointer;
  transition: transform var(--transition), background-color var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.btn-primary {
  background: var(--accent);
  color: #ffffff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.12), 0 6px 20px var(--accent-soft);
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

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

.btn-secondary:hover {
  border-color: var(--text);
  transform: translateY(-1px);
}

/* ---------- Hero ---------- */

.hero {
  padding: clamp(4.5rem, 10vw, 8.5rem) 0 clamp(3.5rem, 7vw, 6rem);
}

.hero-title {
  font-size: clamp(2.4rem, 5.5vw, 4.1rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.08;
  max-width: 18ch;
  margin: 1.25rem 0 1.5rem;
}

.hero-title em {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  letter-spacing: -0.01em;
}

.hero-sub {
  font-size: clamp(1.1rem, 1.8vw, 1.3rem);
  line-height: 1.6;
  color: var(--text-muted);
  max-width: 54ch;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 2.25rem;
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin-top: clamp(3.5rem, 7vw, 5.5rem);
  padding-top: 2.25rem;
  border-top: 1px solid var(--border);
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.stat-value {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.9rem;
  line-height: 1;
  color: var(--text);
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-faint);
  line-height: 1.4;
  max-width: 24ch;
}

/* ---------- Sections ---------- */

.section {
  padding: clamp(4rem, 8vw, 6.5rem) 0;
  border-top: 1px solid var(--border);
}

.section-alt {
  background: var(--bg-alt);
}

/* ---------- About ---------- */

.about {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem 4rem;
  align-items: start;
}

.about-body p + p {
  margin-top: 1rem;
}

.about-body {
  color: var(--text-muted);
  font-size: 1.0625rem;
}

.role-list {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.5rem;
}

.role-list li {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: border-color var(--transition), color var(--transition);
}

.role-list li:hover {
  border-color: var(--accent);
  color: var(--text);
}

/* ---------- Cards ---------- */

.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.card {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  padding: 1.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.card:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.card-title {
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.card-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.card-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 0.75rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.card-list li {
  position: relative;
  padding-left: 1.25rem;
  font-size: 0.925rem;
  color: var(--text-muted);
}

.card-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}

/* ---------- Experience feature ---------- */

.feature {
  padding: clamp(1.75rem, 4vw, 2.75rem);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) + 4px);
}

.feature-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.feature-name {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  font-size: 2rem;
  line-height: 1.1;
}

.feature-role {
  margin-top: 0.25rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
}

.feature-tag {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 0.4rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--accent-soft);
  white-space: nowrap;
}

.feature-desc {
  font-size: 1.125rem;
  color: var(--text);
  max-width: 62ch;
  margin-bottom: 1.5rem;
}

.feature-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.feature-tags li {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  padding: 0.5rem 0.95rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  transition: border-color var(--transition), color var(--transition);
}

.feature-tags li:hover {
  border-color: var(--accent);
  color: var(--text);
}

/* ---------- Philosophy outcomes ---------- */

.grid-four {
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

.outcome {
  padding: 1.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  transition: border-color var(--transition), transform var(--transition);
}

.outcome:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

.outcome h3 {
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 0.5rem;
}

.outcome p {
  font-size: 0.925rem;
  color: var(--text-muted);
}

/* ---------- Projects ---------- */

.project-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.project {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  padding: 1.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.project:hover {
  border-color: var(--border-strong);
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

.project-meta {
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.project-index {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1rem;
  color: var(--text-faint);
}

.project h3 {
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.project p {
  font-size: 0.925rem;
  color: var(--text-muted);
  max-width: 44ch;
}

/* ---------- Security ---------- */

.security {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 2rem 4rem;
  align-items: start;
}

.security-body p {
  color: var(--text-muted);
}

.security-body p + p {
  margin-top: 1rem;
}

.security-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.security-list li {
  position: relative;
  padding: 0.9rem 1.15rem 0.9rem 2.6rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-size: 0.95rem;
  font-weight: 500;
  transition: border-color var(--transition);
}

.security-list li::before {
  content: "";
  position: absolute;
  left: 1.1rem;
  top: 50%;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  transform: translateY(-50%);
}

.security-list li:hover {
  border-color: var(--border-strong);
}

/* ---------- Contact ---------- */

.section-contact {
  background: var(--bg);
  border-top: 1px solid var(--border);
}

.contact {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.contact-title {
  font-size: clamp(2rem, 4.5vw, 3.1rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.1;
  max-width: 22ch;
}

.contact-sub {
  margin-top: 1.25rem;
  color: var(--text-muted);
  max-width: 50ch;
  font-size: 1.125rem;
}

.contact-cta {
  margin-top: 2.5rem;
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem 2.5rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  width: 100%;
}

.contact-links li {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  align-items: center;
}

.contact-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.contact-links a {
  font-weight: 600;
  color: var(--text);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), color var(--transition);
}

.contact-links a:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  font-size: 0.875rem;
  color: var(--text-faint);
}

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

.footer-top {
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition);
}

.footer-top:hover {
  color: var(--text);
}

/* ---------- Reveal animation ---------- */

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .btn,
  .card,
  .project,
  .outcome {
    transition: none;
  }
}

/* ---------- Responsive ---------- */

@media (max-width: 900px) {
  .stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
  }

  .about {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .grid-four {
    grid-template-columns: repeat(2, 1fr);
  }

  .security {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }
}

@media (max-width: 720px) {
  .grid {
    grid-template-columns: 1fr;
  }

  .project-list {
    grid-template-columns: 1fr;
  }

  .nav-links {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    padding: 0 var(--gutter) 1.5rem;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
    display: none;
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links li {
    width: 100%;
  }

  .nav-links a {
    display: block;
    padding: 0.85rem 0;
    font-size: 1.05rem;
    border-bottom: 1px solid var(--border);
  }

  .nav-cta {
    border-bottom: none !important;
    color: var(--accent) !important;
  }

  .menu-toggle {
    display: flex;
  }
}

@media (max-width: 520px) {
  .brand-name {
    display: none;
  }

  .stats {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }

  .grid-four {
    grid-template-columns: 1fr;
  }

  .hero-cta .btn {
    width: 100%;
  }
}