:root {
  --bg: #0b1020;
  --bg-soft: #131a30;
  --card: #172038;
  --card-border: #263154;
  --text: #eef2ff;
  --muted: #9aa7c7;
  --accent: #7c3aed;
  --accent-2: #22d3ee;
  --radius: 16px;
  --shadow: 0 10px 30px rgba(0, 0, 0, .35);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "Cairo", system-ui, sans-serif;
  background:
    radial-gradient(1200px 600px at 85% -10%, rgba(124, 58, 237, .18), transparent 60%),
    radial-gradient(900px 500px at -10% 20%, rgba(34, 211, 238, .10), transparent 60%),
    var(--bg);
  color: var(--text);
  line-height: 1.7;
  min-height: 100vh;
}

.container { width: min(1100px, 92%); margin-inline: auto; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: rgba(11, 16, 32, .8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--card-border);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; padding: .8rem 0; }
.logo { display: flex; align-items: center; gap: .6rem; color: var(--text); text-decoration: none; font-weight: 700; font-size: 1.15rem; }
.logo strong { color: var(--accent-2); }
.logo-mark {
  display: grid; place-items: center;
  width: 34px; height: 34px; border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  font-weight: 900; font-size: 1.2rem;
}
.nav { display: flex; gap: 1.4rem; }
.nav a { color: var(--muted); text-decoration: none; font-weight: 600; transition: color .2s; }
.nav a:hover { color: var(--text); }

/* Hero */
.hero { padding: 4.5rem 0 3rem; text-align: center; }
.hero h1 { font-size: clamp(1.8rem, 4vw, 3rem); font-weight: 900; margin-bottom: .8rem; }
.grad { background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-sub { color: var(--muted); max-width: 560px; margin: 0 auto 2.2rem; }

/* Fact card */
.fact-card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 1.4rem;
  box-shadow: var(--shadow);
  text-align: start;
  display: flex; flex-direction: column; gap: .8rem;
  transition: transform .2s, border-color .2s;
}
.fact-card:hover { transform: translateY(-3px); border-color: var(--accent); }

.fact-card.big {
  max-width: 640px; margin: 0 auto;
  padding: 2rem; text-align: center; align-items: center;
  animation: pop .35s ease;
}
@keyframes pop { from { opacity: 0; transform: scale(.96); } }

.fact-cat {
  align-self: flex-start;
  font-size: .78rem; font-weight: 700;
  padding: .15rem .7rem; border-radius: 999px;
  background: rgba(124, 58, 237, .15);
  color: #c4b5fd;
  border: 1px solid rgba(124, 58, 237, .35);
}
.fact-card.big .fact-cat { align-self: center; }

.fact-text { font-size: 1.05rem; }
.fact-card.big .fact-text { font-size: 1.25rem; font-weight: 600; min-height: 3.4em; display: grid; place-items: center; }

.fact-actions { display: flex; gap: .7rem; margin-top: .4rem; justify-content: center; }

.btn {
  display: inline-flex; align-items: center; gap: .45rem;
  font-family: inherit; font-weight: 700; font-size: .95rem;
  padding: .6rem 1.3rem; border-radius: 12px;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .15s, box-shadow .2s, background .2s;
}
.btn:active { transform: scale(.96); }
.btn.primary {
  background: linear-gradient(135deg, var(--accent), #a855f7);
  color: #fff;
}
.btn.primary:hover { box-shadow: 0 6px 20px rgba(124, 58, 237, .45); }
.btn.ghost { background: transparent; color: var(--muted); border-color: var(--card-border); }
.btn.ghost:hover { color: var(--text); border-color: var(--accent-2); }
.btn.sm { padding: .35rem .8rem; font-size: .82rem; }

/* Library */
.library { padding: 2.5rem 0 4rem; }
.library-head { display: flex; align-items: baseline; gap: .8rem; margin-bottom: 1.4rem; }
.library-head h2 { font-size: 1.5rem; font-weight: 800; }
.count { color: var(--muted); font-size: .9rem; }

.controls { display: flex; flex-direction: column; gap: 1rem; margin-bottom: 1.6rem; }

.search-box {
  display: flex; align-items: center; gap: .6rem;
  background: var(--bg-soft);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: .65rem 1rem;
  color: var(--muted);
}
.search-box:focus-within { border-color: var(--accent-2); color: var(--text); }
.search-box input {
  flex: 1; background: none; border: none; outline: none;
  color: var(--text); font-family: inherit; font-size: 1rem;
}
.search-box input::placeholder { color: var(--muted); }

.chips { display: flex; flex-wrap: wrap; gap: .55rem; }
.chip {
  font-family: inherit; font-size: .85rem; font-weight: 700;
  padding: .4rem 1rem; border-radius: 999px; cursor: pointer;
  background: var(--bg-soft); color: var(--muted);
  border: 1px solid var(--card-border);
  transition: all .2s;
}
.chip:hover { color: var(--text); border-color: var(--accent); }
.chip.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
  gap: 1.1rem;
}

.card-foot { display: flex; justify-content: space-between; align-items: center; margin-top: auto; }

.empty { text-align: center; color: var(--muted); padding: 3rem 0; }

/* Header actions + language toggle */
.header-actions { display: flex; align-items: center; gap: .6rem; }
.lang-btn {
  font-family: inherit; font-weight: 800; font-size: .85rem;
  min-width: 40px; height: 40px; padding: 0 .7rem;
  border-radius: 12px; cursor: pointer;
  background: var(--bg-soft); color: var(--text);
  border: 1px solid var(--card-border);
  transition: all .2s;
}
.lang-btn:hover { border-color: var(--accent-2); color: var(--accent-2); }

/* YouTube button */
.btn.yt { background: #e11d48; color: #fff; }
.btn.yt:hover { background: #be123c; box-shadow: 0 6px 20px rgba(225, 29, 72, .4); }

/* Videos section */
.videos { padding: 3rem 0; }
.section-head {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; flex-wrap: wrap; margin-bottom: 1.4rem;
}
.section-head h2 { font-size: 1.5rem; font-weight: 800; }

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.1rem;
}

.video-card {
  display: block; text-decoration: none; color: var(--text);
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform .2s, border-color .2s;
}
.video-card:hover { transform: translateY(-3px); border-color: var(--accent-2); }

.video-card .thumb { position: relative; aspect-ratio: 16/9; overflow: hidden; }
.video-card .thumb img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform .3s; }
.video-card:hover .thumb img { transform: scale(1.05); }
.video-card .play {
  position: absolute; inset: 0;
  display: grid; place-items: center;
  font-size: 1.6rem; color: #fff;
  background: rgba(11, 16, 32, .35);
  opacity: 0; transition: opacity .2s;
}
.video-card:hover .play { opacity: 1; }
.video-card h3 { font-size: .95rem; font-weight: 700; padding: .9rem 1rem 1.1rem; }

.subscribe-banner {
  margin-top: 2rem;
  display: flex; align-items: center; justify-content: center;
  gap: 1.2rem; flex-wrap: wrap;
  background: var(--bg-soft);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 1.4rem;
  text-align: center;
}
.subscribe-banner p { font-weight: 700; }

/* Footer */
.social { display: flex; justify-content: center; gap: 1rem; margin-bottom: 1rem; }
.social a {
  display: grid; place-items: center;
  width: 40px; height: 40px; border-radius: 12px;
  color: var(--muted);
  background: var(--bg-soft);
  border: 1px solid var(--card-border);
  transition: all .2s;
}
.social a:hover { color: var(--text); border-color: var(--accent); transform: translateY(-2px); }

.hashtags { display: flex; flex-wrap: wrap; justify-content: center; gap: .5rem .9rem; margin-bottom: 1rem; }
.hashtags span { color: var(--accent-2); font-size: .85rem; font-weight: 600; }

/* Footer (original) */
.site-footer { border-top: 1px solid var(--card-border); padding: 2rem 0; }
.footer-inner { display: flex; flex-direction: column; gap: .3rem; text-align: center; }
.muted { color: var(--muted); font-size: .9rem; }

/* Toast */
.toast {
  position: fixed; bottom: 1.5rem; inset-inline-start: 50%;
  transform: translateX(50%) translateY(150%);
  background: var(--accent); color: #fff;
  padding: .6rem 1.4rem; border-radius: 999px;
  font-weight: 700; font-size: .9rem;
  box-shadow: var(--shadow);
  transition: transform .3s ease;
  z-index: 50;
}
.toast.show { transform: translateX(50%) translateY(0); }
html[dir="ltr"] .toast { transform: translateX(-50%) translateY(150%); }
html[dir="ltr"] .toast.show { transform: translateX(-50%) translateY(0); }

@media (max-width: 560px) {
  .nav { gap: .9rem; font-size: .9rem; }
  .hero { padding-top: 3rem; }
}