/* ============================================================
   CYBEROATH CYBERAI — style.css v3.0
   Dark theme · Green #6EC286 accent · Rajdhani + Space Mono
   ============================================================ */

:root {
  --g:          #6EC286;
  --g2:         #4fa36a;
  --g-glow:     rgba(110,194,134,0.30);
  --g-faint:    rgba(110,194,134,0.07);
  --g-mid:      rgba(110,194,134,0.14);
  --dark:       #060d10;
  --deep:       #080f13;
  --panel:      rgba(255,255,255,0.034);
  --panel-h:    rgba(255,255,255,0.06);
  --border:     rgba(255,255,255,0.07);
  --border-g:   rgba(110,194,134,0.20);
  --border-g2:  rgba(110,194,134,0.40);
  --text:       #d4e8da;
  --text2:      #7a9e89;
  --muted:      #3d6050;
  --white:      #edfff4;

  /* tag colours */
  --tag-cs:    #e07070; --tag-cs-bg: rgba(224,112,112,0.10);
  --tag-net:   #70aaee; --tag-net-bg: rgba(112,170,238,0.10);
  --tag-web:   #c792ea; --tag-web-bg: rgba(199,146,234,0.10);

  --radius: 6px;
  --nav-h: 62px;
}

/* ── RESET ─────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', sans-serif;
  background: var(--dark);
  color: var(--text);
  overflow-x: hidden;
  min-height: 100vh;
}

/* ── SCROLLBAR ──────────────────────────────────────────────── */
::-webkit-scrollbar { width: 3px; }
::-webkit-scrollbar-track { background: var(--dark); }
::-webkit-scrollbar-thumb { background: var(--g2); border-radius: 3px; }

/* ── BACKGROUND ─────────────────────────────────────────────── */
.bg-scene {
  position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden;
}
.bg-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(110,194,134,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(110,194,134,0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 30%, black 20%, transparent 100%);
}
.bg-radial {
  position: absolute;
  border-radius: 50%; filter: blur(120px);
  animation: bgFloat 10s ease-in-out infinite;
}
.bg-r1 {
  width: 700px; height: 500px;
  background: radial-gradient(circle, rgba(110,194,134,0.08), transparent 70%);
  top: -180px; left: 50%; transform: translateX(-50%);
}
.bg-r2 {
  width: 350px; height: 350px;
  background: radial-gradient(circle, rgba(110,194,134,0.05), transparent 70%);
  bottom: 10%; right: 2%; animation-delay: -5s;
}
@keyframes bgFloat {
  0%,100% { transform: translateX(-50%) translateY(0); }
  50%      { transform: translateX(-50%) translateY(-24px); }
}

/* ── NAV ────────────────────────────────────────────────────── */
nav {
  position: sticky; top: 0; z-index: 900;
  height: var(--nav-h);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 2.5rem;
  background: rgba(6,13,16,0.75);
  backdrop-filter: blur(28px) saturate(1.6);
  border-bottom: 1px solid var(--border);
}
.nav-left { display: flex; align-items: center; gap: 14px; text-decoration: none; }
.nav-left img { height: 36px; }
.nav-brand {
  font-family: 'Rajdhani', sans-serif;
  font-size: 1.1rem; font-weight: 700;
  letter-spacing: 4px; text-transform: uppercase;
  color: var(--white);
}
.nav-brand em { color: var(--g); font-style: normal; }
.nav-right { display: flex; align-items: center; gap: 10px; }
.nav-pill {
  font-family: 'Space Mono', monospace;
  font-size: 0.58rem; letter-spacing: 2.5px; text-transform: uppercase;
  color: var(--g); border: 1px solid var(--border-g);
  background: var(--g-faint); padding: 6px 14px;
}
.nav-dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--g);
  box-shadow: 0 0 10px var(--g-glow);
  animation: blink 1.6s ease-in-out infinite;
}
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.1} }

/* ── HERO ───────────────────────────────────────────────────── */
.hero {
  position: relative; z-index: 1;
  padding: 96px 2.5rem 56px;
  text-align: center;
  overflow: hidden;
}

/* Scan line effect */
.hero::after {
  content: '';
  position: absolute; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--g), transparent);
  opacity: 0.4;
  animation: scanLine 5s linear infinite;
  pointer-events: none;
}
@keyframes scanLine {
  0%  { top: 0%;   opacity: 0; }
  5%  { opacity: 0.5; }
  95% { opacity: 0.5; }
  100%{ top: 100%; opacity: 0; }
}

.hero-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: 'Space Mono', monospace;
  font-size: 0.58rem; letter-spacing: 3px; text-transform: uppercase;
  color: var(--g); border: 1px solid var(--border-g);
  background: var(--g-faint);
  padding: 6px 18px; margin-bottom: 32px;
  animation: fadeDown 0.7s ease both;
}
.hero-eyebrow-dot {
  width: 5px; height: 5px; border-radius: 50%;
  background: var(--g); box-shadow: 0 0 8px var(--g);
  animation: blink 1.4s ease-in-out infinite;
}
@keyframes fadeDown { from{opacity:0;transform:translateY(-14px)} to{opacity:1;transform:translateY(0)} }

.hero h1 {
  font-family: 'Rajdhani', sans-serif;
  font-size: clamp(2.8rem, 7.5vw, 6rem);
  font-weight: 700; line-height: 1.0;
  letter-spacing: 1px; text-transform: uppercase;
  color: var(--white); margin-bottom: 22px;
  animation: fadeDown 0.8s 0.1s ease both;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--g) 0%, #a8e8be 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: none;
  filter: drop-shadow(0 0 30px rgba(110,194,134,0.35));
}
.hero-sub {
  font-size: 0.95rem; line-height: 1.85;
  color: var(--text2); max-width: 500px;
  margin: 0 auto 48px; font-weight: 300;
  animation: fadeDown 0.85s 0.18s ease both;
}

/* Hero stats row */
.hero-stats {
  display: inline-flex; gap: 0;
  border: 1px solid var(--border-g);
  background: var(--g-faint);
  backdrop-filter: blur(16px);
  margin-bottom: 56px;
  animation: fadeDown 0.9s 0.25s ease both;
}
.hero-stat {
  padding: 16px 32px; text-align: center;
  border-right: 1px solid var(--border-g);
}
.hero-stat:last-child { border-right: none; }
.hs-num {
  font-family: 'Rajdhani', sans-serif;
  font-size: 1.7rem; font-weight: 700;
  color: var(--g); line-height: 1;
  text-shadow: 0 0 20px var(--g-glow);
}
.hs-lbl {
  font-family: 'Space Mono', monospace;
  font-size: 0.52rem; color: var(--muted);
  letter-spacing: 2px; text-transform: uppercase;
  margin-top: 3px;
}

/* ── SEARCH ─────────────────────────────────────────────────── */
.search-wrap {
  position: relative; z-index: 1;
  max-width: 540px; margin: 0 auto 56px;
  padding: 0 2.5rem;
  animation: fadeDown 0.9s 0.32s ease both;
}
.search-box {
  display: flex; align-items: center; gap: 12px;
  background: var(--panel);
  border: 1px solid var(--border);
  backdrop-filter: blur(20px);
  padding: 0 20px;
  transition: border-color .25s, box-shadow .25s;
}
.search-box:focus-within {
  border-color: var(--border-g2);
  box-shadow: 0 0 0 3px var(--g-faint), 0 8px 32px rgba(0,0,0,0.3);
}
.search-box svg { color: var(--g); flex-shrink: 0; width: 16px; height: 16px; }
#searchInput {
  flex: 1; background: transparent; border: none; outline: none;
  color: var(--white); font-family: 'Space Mono', monospace;
  font-size: 0.8rem; padding: 16px 0; letter-spacing: 0.5px;
}
#searchInput::placeholder { color: var(--muted); }

/* ── TABS ───────────────────────────────────────────────────── */
.tabs-wrap {
  position: relative; z-index: 1;
  max-width: 1240px; margin: 0 auto;
  padding: 0 2.5rem;
}
.tabs {
  display: flex; gap: 2px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 44px;
  overflow-x: auto;
}
.tabs::-webkit-scrollbar { height: 0; }
.tab-btn {
  font-family: 'Rajdhani', sans-serif;
  font-size: 0.82rem; font-weight: 600;
  letter-spacing: 2px; text-transform: uppercase;
  background: transparent; border: none; color: var(--text2);
  padding: 12px 20px; cursor: pointer;
  white-space: nowrap; position: relative;
  transition: color .2s;
}
.tab-btn::after {
  content: ''; position: absolute;
  bottom: -1px; left: 0; right: 0; height: 2px;
  background: var(--g);
  transform: scaleX(0); transition: transform .25s cubic-bezier(.4,0,.2,1);
}
.tab-btn.active { color: var(--g); }
.tab-btn.active::after { transform: scaleX(1); }
.tab-btn:hover:not(.active) { color: var(--white); }
.tab-count {
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--g-faint); color: var(--g);
  font-family: 'Space Mono', monospace; font-size: 0.55rem;
  padding: 1px 6px; margin-left: 5px;
}

/* ── MAIN ───────────────────────────────────────────────────── */
main {
  position: relative; z-index: 1;
  max-width: 1240px; margin: 0 auto;
  padding: 0 2.5rem 120px;
}

/* ── SECTION HEADER ─────────────────────────────────────────── */
.section-header {
  display: flex; align-items: center; gap: 16px;
  margin-bottom: 24px;
}
.section-title {
  font-family: 'Space Mono', monospace;
  font-size: 0.58rem; font-weight: 400;
  letter-spacing: 4px; text-transform: uppercase;
  color: var(--muted); white-space: nowrap;
}
.section-line {
  flex: 1; height: 1px;
  background: linear-gradient(90deg, rgba(255,255,255,0.06), transparent);
}

/* ── GRID ───────────────────────────────────────────────────── */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(292px, 1fr));
  gap: 14px; margin-bottom: 56px;
}

/* ── CARD ───────────────────────────────────────────────────── */
.lesson-card {
  position: relative;
  cursor: pointer;
  background: var(--panel);
  border: 1px solid var(--border);
  backdrop-filter: blur(20px) saturate(1.4);
  box-shadow:
    0 2px 8px rgba(0,0,0,0.3),
    inset 0 1px 0 rgba(255,255,255,0.055);
  transform-style: preserve-3d;
  transition:
    transform 0.4s cubic-bezier(.25,.46,.45,.94),
    box-shadow 0.4s ease,
    border-color 0.3s;
  will-change: transform;
  overflow: hidden;
}

/* Top edge glow line */
.lesson-card::before {
  content: '';
  position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, var(--g), transparent);
  opacity: 0; transition: opacity 0.35s;
  z-index: 2;
}
/* Hover shimmer */
.lesson-card::after {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(circle at 30% 20%, rgba(110,194,134,0.07), transparent 65%);
  opacity: 0; transition: opacity 0.4s;
  z-index: 0;
}
.lesson-card:hover {
  border-color: var(--border-g);
  box-shadow:
    0 8px 32px rgba(0,0,0,0.5),
    0 0 40px rgba(110,194,134,0.06),
    inset 0 1px 0 rgba(255,255,255,0.07);
}
.lesson-card:hover::before { opacity: 1; }
.lesson-card:hover::after  { opacity: 1; }
.lesson-card:hover .card-arrow { transform: translateX(5px); }

.card-inner { padding: 24px; position: relative; z-index: 3; }

/* Tags */
.card-tag {
  display: inline-flex; align-items: center; gap: 5px;
  font-family: 'Space Mono', monospace;
  font-size: 0.52rem; letter-spacing: 1.5px; text-transform: uppercase;
  padding: 3px 9px; margin-bottom: 16px;
  border: 1px solid transparent;
}
.card-tag.cs  { color: var(--tag-cs);  background: var(--tag-cs-bg);  border-color: rgba(224,112,112,0.22); }
.card-tag.net { color: var(--tag-net); background: var(--tag-net-bg); border-color: rgba(112,170,238,0.22); }
.card-tag.web { color: var(--tag-web); background: var(--tag-web-bg); border-color: rgba(199,146,234,0.22); }

.card-id {
  font-family: 'Space Mono', monospace;
  font-size: 0.55rem; color: var(--g2);
  letter-spacing: 1.5px; margin-bottom: 8px;
  opacity: 0.65;
}
.card-name {
  font-family: 'Rajdhani', sans-serif;
  font-size: 1.05rem; font-weight: 600;
  line-height: 1.35; color: var(--white);
  letter-spacing: 0.4px; margin-bottom: 22px;
}
.card-footer {
  display: flex; align-items: center; justify-content: space-between;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}
.card-open {
  font-family: 'Space Mono', monospace; font-size: 0.62rem;
  color: var(--g); letter-spacing: 1px; text-transform: uppercase;
  display: flex; align-items: center; gap: 6px;
}
.card-arrow { display: inline-block; transition: transform .25s ease; }
.card-icon { font-size: 1.1rem; opacity: 0.3; }

/* Corner dot pattern */
.card-dots {
  position: absolute; bottom: 0; right: 0;
  width: 72px; height: 72px;
  background-image: radial-gradient(circle, rgba(110,194,134,0.1) 1px, transparent 1px);
  background-size: 9px 9px;
  pointer-events: none; z-index: 1;
}

/* ── NO RESULTS ─────────────────────────────────────────────── */
.no-results {
  text-align: center; padding: 72px 20px;
  color: var(--muted); font-family: 'Space Mono', monospace;
  font-size: 0.72rem; letter-spacing: 2px;
}

/* ── TAB SECTIONS ───────────────────────────────────────────── */
.tab-section { display: none; }
.tab-section.active { display: block; }
.hidden { display: none !important; }

/* ── MODAL ──────────────────────────────────────────────────── */
.modal-overlay {
  display: none; position: fixed; inset: 0; z-index: 9000;
  background: rgba(4,9,12,0.92);
  backdrop-filter: blur(18px);
  flex-direction: column;
  animation: mFadeIn .22s ease both;
}
.modal-overlay.open { display: flex; }
@keyframes mFadeIn { from{opacity:0} to{opacity:1} }

.modal-bar {
  background: rgba(8,14,18,0.98);
  backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--border);
  padding: 0 20px; height: 52px;
  display: flex; align-items: center; justify-content: space-between;
  flex-shrink: 0;
  box-shadow: 0 2px 24px rgba(0,0,0,0.5);
}
.modal-title {
  font-family: 'Rajdhani', sans-serif;
  font-size: 0.88rem; font-weight: 600;
  letter-spacing: 2px; text-transform: uppercase;
  color: var(--g);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
  max-width: calc(100% - 60px);
}
.modal-close {
  background: var(--panel); border: 1px solid var(--border);
  color: var(--text2); width: 34px; height: 34px;
  cursor: pointer; font-size: 0.95rem;
  display: flex; align-items: center; justify-content: center;
  transition: all .18s; flex-shrink: 0;
}
.modal-close:hover {
  color: var(--white); border-color: var(--border-g);
  background: var(--g-mid);
}
.modal-frame { flex: 1; width: 100%; border: none; background: #fff; }

/* ── FOOTER ─────────────────────────────────────────────────── */
footer {
  position: relative; z-index: 1;
  border-top: 1px solid var(--border);
  padding: 30px 2.5rem; text-align: center;
  background: rgba(6,13,16,0.7);
  backdrop-filter: blur(12px);
}
footer img { height: 28px; opacity: 0.4; margin: 0 auto 10px; display: block; }
footer p {
  font-family: 'Space Mono', monospace;
  font-size: 0.55rem; color: var(--muted);
  letter-spacing: 2.5px; text-transform: uppercase;
}

/* ── PARTICLES ──────────────────────────────────────────────── */
.particles { position: fixed; inset: 0; pointer-events: none; z-index: 0; overflow: hidden; }
.particle {
  position: absolute; width: 2px; height: 2px;
  background: var(--g); border-radius: 50%;
  opacity: 0; animation: pFly linear infinite;
}
@keyframes pFly {
  0%   { opacity:0; transform:translateY(0) scale(1); }
  10%  { opacity:0.5; }
  90%  { opacity:0.15; }
  100% { opacity:0; transform:translateY(-110vh) scale(0.5); }
}

/* ── RESPONSIVE ─────────────────────────────────────────────── */
@media(max-width:640px) {
  .grid { grid-template-columns: 1fr; }
  nav { padding: 0 1.2rem; }
  .hero { padding: 72px 1.2rem 40px; }
  .hero-stats { flex-direction: column; gap: 0; width: 100%; }
  .hero-stat { border-right: none; border-bottom: 1px solid var(--border-g); }
  .hero-stat:last-child { border-bottom: none; }
  .search-wrap { padding: 0 1.2rem; }
  main, .tabs-wrap { padding-left: 1.2rem; padding-right: 1.2rem; }
}