/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0a0c10;
  --bg2:       #0d1117;
  --bg3:       #161b22;
  --bg4:       #21262d;
  --border:    #30363d;
  --text:      #c9d1d9;
  --text-dim:  #8b949e;
  --text-bright: #f0f6fc;
  --green:     #39d353;
  --green-dim: #1a7f37;
  --blue:      #58a6ff;
  --blue-dim:  #1f6feb;
  --red:       #f85149;
  --red-dim:   #8b1a1a;
  --purple:    #bc8cff;
  --purple-dim:#6e40c9;
  --yellow:    #d29922;
  --cyan:      #79c0ff;
  --accent:    #39d353;
  --radius:    8px;
  --radius-lg: 12px;
  --font-mono: 'Cascadia Code', 'Fira Code', 'JetBrains Mono', 'Courier New', monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --transition: 0.2s ease;
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* ===== SCANLINES OVERLAY ===== */
.scanlines {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  z-index: 9999;
  background: repeating-linear-gradient(
    to bottom,
    transparent 0px,
    transparent 3px,
    rgba(0,0,0,0.04) 3px,
    rgba(0,0,0,0.04) 4px
  );
}

/* ===== NAVBAR ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 2rem;
  padding: 0 2rem;
  height: 56px;
  background: rgba(13, 17, 23, 0.92);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
}

.nav-brand {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 700;
  white-space: nowrap;
}
.brand-bracket { color: var(--green); }
.brand-text { color: var(--text-bright); letter-spacing: 2px; }

.nav-links {
  display: flex;
  list-style: none;
  gap: 0.25rem;
  margin-left: auto;
}
.nav-links a {
  display: block;
  padding: 0.35rem 0.9rem;
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.875rem;
  border-radius: var(--radius);
  transition: color var(--transition), background var(--transition);
  font-family: var(--font-mono);
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--text-bright);
  background: var(--bg3);
}
.nav-links a.active { color: var(--green); }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 1.4rem;
  cursor: pointer;
  margin-left: auto;
}

/* ===== SECTION TITLES ===== */
.section-title {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-bright);
  margin-bottom: 1.5rem;
}
.section-title .accent { color: var(--green); margin-right: 0.5rem; }

/* ===== BUTTONS ===== */
.btn-outline {
  display: inline-block;
  margin-top: 1.5rem;
  padding: 0.6rem 1.4rem;
  border: 1px solid var(--green);
  color: var(--green);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  text-decoration: none;
  border-radius: var(--radius);
  transition: background var(--transition), color var(--transition);
}
.btn-outline:hover {
  background: var(--green);
  color: var(--bg);
}

/* ===== TAGS / BADGES ===== */
.tag {
  display: inline-block;
  padding: 0.15rem 0.55rem;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}
.tag-htb  { background: rgba(159, 239, 0, 0.12); color: #9fef00; border: 1px solid rgba(159,239,0,0.3); }
.tag-thm  { background: rgba(255, 60, 60, 0.12);  color: #ff3c3c; border: 1px solid rgba(255,60,60,0.3); }
.tag-ctf  { background: rgba(88, 166, 255, 0.12); color: var(--blue); border: 1px solid rgba(88,166,255,0.3); }
.tag-vh   { background: rgba(188, 140, 255, 0.12); color: var(--purple); border: 1px solid rgba(188,140,255,0.3); }
.tag-easy   { background: rgba(57,211,83,0.12);  color: var(--green);  border: 1px solid rgba(57,211,83,0.3); }
.tag-medium { background: rgba(210,153,34,0.12); color: #e3b341;       border: 1px solid rgba(210,153,34,0.3); }
.tag-hard   { background: rgba(248,81,73,0.12);  color: var(--red);    border: 1px solid rgba(248,81,73,0.3); }
.tag-insane { background: rgba(188,140,255,0.12);color: var(--purple);  border: 1px solid rgba(188,140,255,0.3); }
.tag-info   { background: rgba(88,166,255,0.12); color: var(--blue);   border: 1px solid rgba(88,166,255,0.3); }
.tag-generic{ background: var(--bg3); color: var(--text-dim); border: 1px solid var(--border); }

/* ===== FOOTER ===== */
.footer {
  margin-top: 4rem;
  border-top: 1px solid var(--border);
  padding: 1.25rem 2rem;
}
.footer-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-dim);
}
.footer-brand { color: var(--green); font-weight: 700; }
.footer-sep { color: var(--border); }

/* ===== WRITEUP CARD (shared) ===== */
.writeup-card {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 0.75rem 1.5rem;
  padding: 1rem 1.25rem;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--text);
  transition: border-color var(--transition), background var(--transition);
  position: relative;
  overflow: hidden;
}
.writeup-card::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 3px;
  background: var(--green);
  opacity: 0;
  transition: opacity var(--transition);
}
.writeup-card:hover { border-color: var(--green); background: var(--bg3); }
.writeup-card:hover::before { opacity: 1; }

.writeup-card h3 {
  font-size: 0.95rem;
  color: var(--text-bright);
  font-family: var(--font-mono);
}
.writeup-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.35rem;
}
.writeup-date {
  font-size: 0.75rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
}
.writeup-arrow {
  font-size: 1.1rem;
  color: var(--text-dim);
  transition: color var(--transition);
}
.writeup-card:hover .writeup-arrow { color: var(--green); }

/* ===== PAGE HERO ===== */
.page-hero {
  padding: 3rem 2rem 2rem;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg2) 0%, var(--bg) 100%);
}
.page-hero h1 {
  font-family: var(--font-mono);
  font-size: 1.8rem;
  color: var(--text-bright);
}
.page-hero h1 span { color: var(--green); }
.page-hero p {
  margin-top: 0.5rem;
  color: var(--text-dim);
  max-width: 580px;
}

/* ===== FILTER BAR ===== */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 1.25rem 2rem;
  border-bottom: 1px solid var(--border);
  background: var(--bg2);
}
.filter-btn {
  padding: 0.3rem 0.85rem;
  border: 1px solid var(--border);
  background: var(--bg3);
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  border-radius: 20px;
  cursor: pointer;
  transition: all var(--transition);
}
.filter-btn:hover,
.filter-btn.active {
  border-color: var(--green);
  color: var(--green);
  background: rgba(57,211,83,0.08);
}

/* ===== SEARCH ===== */
.search-wrap {
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--border);
}
.search-input {
  width: 100%;
  max-width: 420px;
  padding: 0.6rem 1rem;
  background: var(--bg3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  outline: none;
  transition: border-color var(--transition);
}
.search-input::placeholder { color: var(--text-dim); }
.search-input:focus { border-color: var(--blue); }

/* ===== CONTENT AREA ===== */
.content-area {
  padding: 2rem;
  max-width: 1100px;
}

/* ===== EMPTY STATE ===== */
.empty-state {
  text-align: center;
  padding: 3rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}
.empty-state strong { display: block; font-size: 1.1rem; margin-bottom: 0.5rem; color: var(--text); }

/* ===== MOBILE ===== */
@media (max-width: 768px) {
  .nav-links { display: none; flex-direction: column; position: absolute; top: 56px; left: 0; right: 0; background: var(--bg2); border-bottom: 1px solid var(--border); padding: 0.5rem; }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
  .content-area { padding: 1.25rem; }
  .page-hero { padding: 2rem 1.25rem 1.5rem; }
  .filter-bar { padding: 1rem 1.25rem; }
  .search-wrap { padding: 0.75rem 1.25rem; }
}