/* ═══════════════════════════════════════════
   VARIABLES & RESET
═══════════════════════════════════════════ */
:root {
  --bg-primary:    #0a0d12;
  --bg-secondary:  #0f1318;
  --bg-card:       #131920;
  --bg-card-hover: #182130;

  --accent:        #4fa3e0;
  --accent-dim:    rgba(79, 163, 224, 0.12);
  --accent-glow:   rgba(79, 163, 224, 0.25);

  --text-primary:  #e8edf2;
  --text-secondary:#8fa3b8;
  --text-muted:    #4d6070;

  --border:        rgba(79, 163, 224, 0.15);
  --border-card:   rgba(255, 255, 255, 0.06);

  --font-sans:     'Inter', system-ui, sans-serif;
  --font-mono:     'Roboto Mono', 'Courier New', monospace;

  --radius-sm:     6px;
  --radius-md:     12px;
  --radius-lg:     20px;

  --shadow-card:   0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-accent: 0 0 32px rgba(79, 163, 224, 0.15);

  --nav-h:         64px;
  --transition:    0.2s ease;
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

/* ═══════════════════════════════════════════
   UTILITIES
═══════════════════════════════════════════ */
.mono        { font-family: var(--font-mono); }
.accent      { color: var(--accent); }
.container   { width: 100%; max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }

/* ═══════════════════════════════════════════
   BUTTONS
═══════════════════════════════════════════ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .65rem 1.4rem;
  border-radius: var(--radius-sm);
  font-size: .9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid transparent;
  white-space: nowrap;
}
.btn svg { width: 16px; height: 16px; flex-shrink: 0; }

.btn-primary {
  background: var(--accent);
  color: #06090f;
  font-weight: 600;
}
.btn-primary:hover {
  background: #6bb8f0;
  box-shadow: 0 0 24px var(--accent-glow);
  transform: translateY(-1px);
}

.btn-outline {
  border-color: var(--border);
  color: var(--text-secondary);
  background: transparent;
}
.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

.btn-sm { padding: .45rem 1rem; font-size: .82rem; }

/* ═══════════════════════════════════════════
   NAVBAR
═══════════════════════════════════════════ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 100;
  background: rgba(10, 13, 18, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-card);
  transition: box-shadow var(--transition);
}
.navbar.scrolled { box-shadow: 0 4px 32px rgba(0,0,0,0.5); }

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: .05em;
  transition: color var(--transition);
}
.nav-logo .mono { color: var(--accent); }
.nav-logo:hover { color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
}
.nav-links a {
  font-size: .88rem;
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: .25rem 0;
  transition: color var(--transition);
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  width: 0; height: 1px;
  background: var(--accent);
  transition: width var(--transition);
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: .4rem;
}
.nav-toggle span {
  display: block;
  width: 24px; height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: all var(--transition);
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ═══════════════════════════════════════════
   HERO
═══════════════════════════════════════════ */
.hero {
  position: relative;
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 3rem;
  padding: calc(var(--nav-h) + 4rem) 1.5rem 4rem;
  max-width: 1100px;
  margin: 0 auto;
  overflow: hidden;
}

.hero-bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(var(--border-card) 1px, transparent 1px),
    linear-gradient(90deg, var(--border-card) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: -1;
  mask-image: radial-gradient(ellipse 80% 80% at 50% 20%, black 0%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 80% 80% at 50% 20%, black 0%, transparent 80%);
}

.hero-label {
  font-size: .8rem;
  color: var(--accent);
  letter-spacing: .08em;
  margin-bottom: .75rem;
}

.hero-name {
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.02em;
  margin-bottom: .75rem;
}

.hero-tagline {
  font-family: var(--font-mono);
  font-size: clamp(.9rem, 2vw, 1.1rem);
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  padding: .4rem .8rem;
  background: var(--accent-dim);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: inline-block;
}

.hero-desc {
  color: var(--text-secondary);
  font-size: .95rem;
  max-width: 500px;
  margin-bottom: 2rem;
  line-height: 1.8;
}
.hero-desc strong { color: var(--text-primary); font-weight: 500; }

.hero-cta { display: flex; gap: 1rem; flex-wrap: wrap; }

/* Terminal widget */
.hero-terminal {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card), var(--shadow-accent);
  overflow: hidden;
  max-width: 440px;
  justify-self: center;
}
.terminal-bar {
  display: flex;
  align-items: center;
  gap: .5rem;
  padding: .6rem 1rem;
  background: rgba(255,255,255,0.04);
  border-bottom: 1px solid var(--border-card);
}
.dot {
  width: 12px; height: 12px;
  border-radius: 50%;
}
.dot.red    { background: #ff5f57; }
.dot.yellow { background: #febc2e; }
.dot.green  { background: #28c840; }
.terminal-title {
  font-size: .75rem;
  color: var(--text-muted);
  margin-left: auto;
}
.terminal-body {
  padding: 1.25rem 1.5rem;
  font-size: .82rem;
  line-height: 1.9;
  color: var(--text-secondary);
  min-height: 200px;
}
.terminal-body .t-prompt { color: var(--accent); }
.terminal-body .t-cmd    { color: var(--text-primary); }
.terminal-body .t-out    { color: #7ec8a0; }
.terminal-body .t-cursor {
  display: inline-block;
  width: 8px; height: 15px;
  background: var(--accent);
  vertical-align: middle;
  animation: blink .9s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* ═══════════════════════════════════════════
   SECTIONS (shared)
═══════════════════════════════════════════ */
.section { padding: 6rem 0; }
.section-alt { background: var(--bg-secondary); }

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

.section-tag {
  font-size: .75rem;
  color: var(--accent);
  letter-spacing: .12em;
  text-transform: uppercase;
  display: block;
  margin-bottom: .5rem;
}
.section-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -.02em;
  margin-bottom: .5rem;
}
.section-subtitle {
  color: var(--text-secondary);
  font-size: .95rem;
}

/* ═══════════════════════════════════════════
   ABOUT
═══════════════════════════════════════════ */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: .95rem;
  line-height: 1.85;
}

.about-list {
  margin-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: .6rem;
}
.about-list li {
  display: flex;
  align-items: center;
  gap: .75rem;
  font-size: .9rem;
  color: var(--text-secondary);
}

.about-skills {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.skill-card:hover {
  border-color: var(--accent);
  box-shadow: 0 0 24px var(--accent-glow);
}
.skill-icon {
  flex-shrink: 0;
  width: 38px; height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-dim);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--accent);
}
.skill-icon svg { width: 18px; height: 18px; }
.skill-card h3 {
  font-size: .9rem;
  font-weight: 600;
  margin-bottom: .25rem;
  color: var(--text-primary);
}
.skill-card p {
  font-size: .8rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ═══════════════════════════════════════════
   CERTYFIKATY
═══════════════════════════════════════════ */
.certs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
}

.cert-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}
.cert-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-card), 0 0 28px var(--accent-glow);
  transform: translateY(-3px);
}
.cert-card--placeholder {
  border-style: dashed;
  opacity: .5;
}
.cert-card--placeholder:hover { transform: none; border-color: var(--text-muted); box-shadow: none; }

.cert-badge {
  width: 44px; height: 44px;
  background: var(--accent-dim);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}
.cert-badge svg { width: 22px; height: 22px; }

.cert-issuer {
  font-size: .72rem;
  color: var(--accent);
  letter-spacing: .08em;
  text-transform: uppercase;
}
.cert-name {
  font-size: 1.15rem;
  font-weight: 700;
  margin: .2rem 0 .4rem;
}
.cert-desc {
  font-size: .82rem;
  color: var(--text-secondary);
  line-height: 1.6;
  flex-grow: 1;
}

.cert-link {
  align-self: flex-start;
  margin-top: auto;
}
.cert-link:hover {
  box-shadow: 0 0 16px var(--accent-glow);
}

/* ═══════════════════════════════════════════
   CTF
═══════════════════════════════════════════ */
.ctf-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}

.ctf-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: .85rem;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}
.ctf-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card);
}

.ctf-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.ctf-platform {
  font-size: .72rem;
  color: var(--text-muted);
  letter-spacing: .06em;
}
.ctf-difficulty {
  font-size: .7rem;
  font-weight: 600;
  padding: .2rem .5rem;
  border-radius: 4px;
  font-family: var(--font-mono);
  letter-spacing: .05em;
}
.ctf-easy   { background: rgba(40,200,64,.12); color: #28c840; }
.ctf-medium { background: rgba(254,188,46,.12); color: #febc2e; }
.ctf-hard   { background: rgba(255,95,87,.12);  color: #ff5f57; }

.ctf-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}
.ctf-excerpt {
  font-size: .83rem;
  color: var(--text-secondary);
  line-height: 1.7;
  flex-grow: 1;
}
.ctf-tags {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
}

.tag {
  font-size: .7rem;
  padding: .2rem .55rem;
  background: var(--accent-dim);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--accent);
  letter-spacing: .04em;
}

/* ═══════════════════════════════════════════
   RESEARCH
═══════════════════════════════════════════ */
.research-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.research-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.5rem 2rem;
  padding: 2rem 0;
  border-bottom: 1px solid var(--border-card);
  transition: background var(--transition);
}
.research-item:last-child { border-bottom: none; }

.research-date {
  font-size: .78rem;
  color: var(--text-muted);
  padding-top: .3rem;
  letter-spacing: .05em;
}
.research-type {
  font-size: .72rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .1em;
  margin-bottom: .4rem;
}
.research-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: .6rem;
}
.research-title:hover { color: var(--accent); }
.research-abstract {
  font-size: .85rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: .9rem;
}
.research-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: .5rem;
}
.research-link {
  font-size: .78rem;
  color: var(--accent);
  margin-left: auto;
  transition: opacity var(--transition);
}
.research-link:hover { opacity: .75; }

/* ═══════════════════════════════════════════
   FOOTER
═══════════════════════════════════════════ */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-card);
  padding: 3rem 0 2rem;
}
.footer-inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}
.footer-brand p {
  font-size: .85rem;
  color: var(--text-secondary);
  margin-top: .5rem;
  line-height: 1.6;
}
.footer-links {
  display: flex;
  gap: 1rem;
  align-items: center;
  flex-wrap: wrap;
}
.footer-social {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-size: .85rem;
  color: var(--text-secondary);
  padding: .5rem .9rem;
  border: 1px solid var(--border-card);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}
.footer-social svg { width: 16px; height: 16px; }
.footer-social:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}
.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-card);
  text-align: center;
  font-size: .78rem;
  color: var(--text-muted);
}

/* ═══════════════════════════════════════════
   RESPONSIVE
═══════════════════════════════════════════ */
@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    padding-top: calc(var(--nav-h) + 3rem);
  }
  .hero-desc  { margin: 0 auto 2rem; }
  .hero-cta   { justify-content: center; }
  .hero-terminal { justify-self: center; width: 100%; max-width: 440px; }

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

@media (max-width: 700px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: var(--nav-h); left: 0; right: 0;
    background: rgba(10, 13, 18, 0.97);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 1rem 0 2rem;
    border-bottom: 1px solid var(--border-card);
    transform: translateY(-110%);
    opacity: 0;
    transition: transform .3s ease, opacity .3s ease;
    pointer-events: none;
  }
  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }
  .nav-links a {
    padding: .9rem 2rem;
    font-size: 1rem;
    width: 100%;
    text-align: center;
  }

  .research-item { grid-template-columns: 1fr; gap: .5rem; }
  .research-date { padding: 0; }
  .research-link { margin-left: 0; }

  .certs-grid { grid-template-columns: 1fr; }
  .ctf-grid   { grid-template-columns: 1fr; }
}

/* ═══════════════════════════════════════════
   ARTICLE / WALKTHROUGH SUBPAGES
═══════════════════════════════════════════ */
.article-hero {
  padding: 7rem 0 3rem;
  border-bottom: 1px solid var(--border);
}
.breadcrumb {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-family: var(--mono);
  font-size: .8rem;
  color: var(--muted);
  margin-bottom: 2rem;
}
.breadcrumb a { color: var(--accent); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb-sep { color: var(--border); }

.article-meta-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .75rem;
  margin-bottom: 1.25rem;
}
.article-date { font-family: var(--mono); font-size: .8rem; color: var(--muted); }

.article-hero h1 {
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 1rem;
}
.article-abstract {
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 680px;
  line-height: 1.75;
}

.article-body {
  padding: 3rem 0 5rem;
}
.article-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 3rem;
  align-items: start;
}
.article-toc {
  position: sticky;
  top: 5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
}
.article-toc h4 {
  font-family: var(--mono);
  font-size: .75rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: .08em;
  margin-bottom: 1rem;
}
.article-toc ol {
  list-style: none;
  counter-reset: toc;
  display: flex;
  flex-direction: column;
  gap: .5rem;
}
.article-toc ol li { counter-increment: toc; }
.article-toc ol li a {
  display: flex;
  gap: .6rem;
  align-items: baseline;
  font-size: .85rem;
  color: var(--muted);
  text-decoration: none;
  transition: color .2s;
}
.article-toc ol li a::before {
  content: counter(toc, decimal-leading-zero);
  font-family: var(--mono);
  font-size: .7rem;
  color: var(--accent);
  flex-shrink: 0;
}
.article-toc ol li a:hover { color: var(--text); }

.prose { max-width: 720px; }
.prose h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 2.5rem 0 1rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--border);
  scroll-margin-top: 5rem;
}
.prose h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--accent);
  margin: 1.75rem 0 .75rem;
}
.prose p { line-height: 1.8; color: var(--muted); margin-bottom: 1rem; }
.prose p strong { color: var(--text); }
.prose ul, .prose ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
  display: flex;
  flex-direction: column;
  gap: .4rem;
}
.prose li { color: var(--muted); line-height: 1.7; }
.prose li strong { color: var(--text); }

.prose .terminal-block {
  background: #0d1117;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin: 1.5rem 0;
  overflow: hidden;
}
.prose .terminal-block .terminal-bar {
  padding: .5rem .75rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: .4rem;
}
.prose .terminal-block pre {
  padding: 1rem 1.25rem;
  font-family: var(--mono);
  font-size: .82rem;
  line-height: 1.7;
  color: #c9d1d9;
  overflow-x: auto;
  margin: 0;
}
.prose .terminal-block pre .cmd { color: #58a6ff; }
.prose .terminal-block pre .out { color: #8b949e; }
.prose .terminal-block pre .highlight { color: #3fb950; }
.prose .terminal-block pre .warn { color: #d29922; }

.info-box {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
}
.info-box p { margin: 0; color: var(--text); font-size: .9rem; }

.flag-box {
  display: flex;
  align-items: center;
  gap: .75rem;
  background: color-mix(in srgb, #3fb950 8%, transparent);
  border: 1px solid color-mix(in srgb, #3fb950 30%, transparent);
  border-radius: var(--radius);
  padding: .9rem 1.25rem;
  margin: 1rem 0;
  font-family: var(--mono);
  font-size: .85rem;
}
.flag-box .flag-label { color: #3fb950; font-weight: 600; flex-shrink: 0; }
.flag-box .flag-value { color: var(--muted); word-break: break-all; }

.machine-info-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}
.machine-info-card .info-item label {
  display: block;
  font-family: var(--mono);
  font-size: .7rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: .08em;
  margin-bottom: .25rem;
}
.machine-info-card .info-item span { font-weight: 500; font-size: .9rem; }

@media (max-width: 900px) {
  .article-layout { grid-template-columns: 1fr; }
  .article-toc { position: static; }
}

/* ═══════════════════════════════════════════
   SCROLL REVEAL
═══════════════════════════════════════════ */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .6s ease, transform .6s ease;
}
[data-reveal].visible {
  opacity: 1;
  transform: translateY(0);
}