:root {
  --primary: #22d3ee;
  --secondary: #818cf8;
  --dark: #0f172a;
  --glass: rgba(255,255,255,0.08);
}
* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Vazirmatn', sans-serif; }
html { scroll-behavior: smooth; }
body { background: linear-gradient(135deg, #0f172a, #1e293b); color: white; min-height: 100vh; }

/* ── HEADER ── */
header {
  position: sticky; top: 0; z-index: 100;
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 5%;
  background: rgba(15,23,42,0.92);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(255,255,255,0.1);
  gap: 10px;
}

nav { display: flex; flex-wrap: wrap; justify-content: center; width: 100%; }
nav a {
  color: #cbd5e1; text-decoration: none; font-size: 18px;
  padding: 6px 12px; border-radius: 8px; transition: 0.25s;
}
nav a:hover { background: var(--glass); color: var(--primary); }

.cta-btn {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #000; padding: 9px 16px; border-radius: 10px;
  text-decoration: none; font-weight: bold; font-size: 13px; transition: 0.3s; white-space: nowrap;
}
.cta-btn:hover { transform: scale(1.07); box-shadow: 0 0 15px rgba(34,211,238,0.6); }

/* ── HERO ── */
.hero { text-align: center; padding: 90px 10%; }
.hero h2 { font-size: 32px; margin-bottom: 20px; }
.hero p { color: #cbd5f5; margin-bottom: 30px; }

/* ── FEATURES ── */
.features {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px; padding: 40px 8%;
}
.card {
  background: var(--glass); text-align: center; padding: 20px;
  border-radius: 14px; backdrop-filter: blur(10px); transition: 0.3s;
  border: 1px solid rgba(255,255,255,0.08);
}
.card:hover { transform: translateY(-6px); box-shadow: 0 10px 25px rgba(0,0,0,0.3); }
.card h3 { color: var(--primary); margin-bottom: 10px; }

/* ── SECTION TITLES ── */
.section-title {
  text-align: center; padding: 50px 8% 10px;
  font-size: 26px; color: var(--primary);
}
.section-sub { text-align: center; color: #94a3b8; margin-bottom: 30px; font-size: 14px; }

/* ── ABOUT ── */
#about { padding: 20px 8% 50px; }
.about-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.about-card {
  background: var(--glass); border-radius: 14px; padding: 24px;
  border: 1px solid rgba(255,255,255,0.08);
}
.about-card h3 { color: var(--secondary); margin-bottom: 10px; font-size: 18px; }
.about-card p { color: #cbd5e1; line-height: 1.8; font-size: 14px; text-align: justify; }

/* ── INSTRUCTORS ── */
#instructors { padding: 20px 8% 50px; }
.instructors-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 24px;
}
.instructor-card {
  background: var(--glass); border-radius: 16px; padding: 24px 20px;
  border: 1px solid rgba(255,255,255,0.08); text-align: center; transition: 0.3s;
}
.instructor-card:hover { transform: translateY(-6px); box-shadow: 0 12px 30px rgba(0,0,0,0.35); }
.instructor-card img {
  width: 100px; height: 100px; border-radius: 50%; object-fit: cover;
  border: 3px solid var(--primary); margin-bottom: 14px;
}
.instructor-card h3 { font-size: 16px; margin-bottom: 6px; }
.instructor-card .title { color: var(--secondary); font-size: 13px; margin-bottom: 10px; }
.instructor-card .summary { color: #94a3b8; font-size: 12px; line-height: 1.7; margin-bottom: 14px; }
.instructor-actions { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
.btn-sm {
  font-size: 12px; padding: 6px 12px; border-radius: 8px; cursor: pointer;
  border: none; font-family: 'Vazirmatn', sans-serif; transition: 0.25s;
}
.btn-detail { background: rgba(34,211,238,0.15); color: var(--primary); border: 1px solid var(--primary); }
.btn-detail:hover { background: var(--primary); color: #000; }
.btn-video { background: rgba(239,68,68,0.15); color: #f87171; border: 1px solid #f87171; }
.btn-video:hover { background: #ef4444; color: white; }

    .btn-book {
      display: block; margin-top: 14px; text-align: center; text-decoration: none;
      padding: 10px 16px; border-radius: 10px; font-size: 13px; font-weight: bold;
      font-family: 'Vazirmatn', sans-serif;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      color: #000; transition: 0.3s;
    }
    .btn-book:hover { transform: scale(1.04); box-shadow: 0 0 16px rgba(34,211,238,0.55); }

    .btn-linkedin {
      display: flex; align-items: center; justify-content: center; gap: 6px;
      margin-top: 8px; padding: 8px 16px; border-radius: 10px;
      background: rgba(10,102,194,0.15); color: #7ab3f5;
      border: 1px solid #7ab3f5; text-decoration: none;
      font-size: 12px; font-family: 'Vazirmatn', sans-serif; transition: 0.25s;
    }
    .btn-linkedin svg { width: 14px; height: 14px; fill: #7ab3f5; flex-shrink: 0; }
    .btn-linkedin:hover { background: #0a66c2; color: white; border-color: #0a66c2; }
    .btn-linkedin:hover svg { fill: white; }

/* ── MODAL ── */
.modal-overlay {
  display: none; position: fixed; inset: 0; z-index: 200;
  background: rgba(0,0,0,0.75); backdrop-filter: blur(4px);
  align-items: center; justify-content: center; padding: 20px;
}
.modal-overlay.active { display: flex; }
.modal-box {
  background: #1e293b; border-radius: 16px; padding: 30px;
  max-width: 560px; width: 100%; position: relative;
  border: 1px solid rgba(255,255,255,0.12); max-height: 85vh; overflow-y: auto;
}
.modal-close {
  position: absolute; top: 14px; left: 14px;
  background: none; border: none; color: #94a3b8;
  font-size: 22px; cursor: pointer; line-height: 1;
}
.modal-close:hover { color: white; }
.modal-box h2 { color: var(--primary); margin-bottom: 6px; font-size: 20px; }
.modal-box .modal-title { color: var(--secondary); font-size: 14px; margin-bottom: 16px; }
.modal-box p { color: #cbd5e1; font-size: 14px; line-height: 1.9; margin-bottom: 12px; }
.modal-box ul { color: #cbd5e1; font-size: 14px; line-height: 2; padding-right: 20px; }
.modal-box ul li::marker { color: var(--primary); }

/* video modal */
.modal-video { max-width: 720px; }
.video-wrapper { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; border-radius: 10px; }
.video-wrapper iframe { position: absolute; top: 0; left: 0; width: 100%; height: 100%; border: none; }

/* ── CERTIFICATES ── */
#certificates { padding: 20px 8% 50px; }
.certs-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; }
.cert-card {
  background: var(--glass); border-radius: 14px; overflow: hidden;
  border: 1px solid rgba(255,255,255,0.08); transition: 0.3s; cursor: zoom-in;
}
.modal-cert {
  width: 90vw;
  max-width: 90vw;
  max-height: 90vh;
  height: auto;
  padding: 40px 20px 20px;
  overflow: hidden !important;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-sizing: border-box;
}
.modal-cert img {
  display: block;
  width: auto;
  height: auto;
  max-width: calc(90vw - 40px);
  max-height: calc(90vh - 100px);
  object-fit: contain;
  border-radius: 10px;
  flex-shrink: 1;
}
#certModalCaption { text-align: center; margin-top: 10px; color: #cbd5e1; font-size: 14px; }
.cert-card:hover { transform: translateY(-5px); box-shadow: 0 10px 25px rgba(0,0,0,0.3); }
.cert-card img { width: 100%; height: 160px; object-fit: cover; display: block; }
.cert-card .cert-info { padding: 14px; }
.cert-card .cert-info h4 { font-size: 14px; color: var(--primary); margin-bottom: 4px; }
.cert-card .cert-info p { font-size: 12px; color: #94a3b8; }

/* ── FOOTER ── */
footer { text-align: center; padding: 30px 10%; margin-top: 20px; background: var(--glass); backdrop-filter: blur(10px); }
.email { margin-top: 15px; color: #94a3b8; direction: ltr; }
.socials { margin-top: 20px; }
.socials a {
  margin: 0 10px; display: inline-flex; width: 42px; height: 42px;
  align-items: center; justify-content: center; border-radius: 50%;
  background: rgba(255,255,255,0.05); transition: 0.3s;
}
.socials svg { width: 20px; height: 20px; fill: white; }
.socials a:hover { transform: translateY(-4px) scale(1.1); background: linear-gradient(135deg, #22d3ee, #818cf8); box-shadow: 0 0 12px rgba(34,211,238,0.5); }
.footer-text { font-size: 13px; color: #94a3b8; margin-top: 15px; padding: 10px 15px; display: inline-block; border-radius: 8px; }
.footer-logo { margin-top: 16px; }
.footer-logo img { height: 36px; object-fit: contain; opacity: 0.8; }

@media (max-width: 768px) {
  .hero h2 { font-size: 24px; }
  header { flex-wrap: wrap; gap: 8px; }
  nav { order: 3; width: 100%; flex-wrap: nowrap; justify-content: space-between; }
  nav a { font-size: 13px; padding: 5px 6px; }
}