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

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #0f172a;
  background-color: #020617;
}

img { max-width: 100%; display: block; }

a { color: inherit; text-decoration: none; }

.container {
  width: min(1120px, 100% - 2rem);
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(15, 23, 42, 0.96);
  backdrop-filter: blur(14px);
  color: #e5e7eb;
  border-bottom: 1px solid rgba(148, 163, 184, 0.3);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 0.75rem;
}

.logo {
  font-weight: 700;
  letter-spacing: 0.03em;
  font-size: 1.1rem;
}

.logo span { color: #38bdf8; }

nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.9rem;
}

nav a {
  padding: 0.25rem 0.5rem;
  border-radius: 999px;
  transition: background-color 0.2s ease, box-shadow 0.2s ease;
}

nav a:hover {
  background-color: rgba(15, 23, 42, 1);
  box-shadow: 0 0 12px rgba(56, 189, 248, 0.6);
}

/* Hero with background image */

.hero {
  position: relative;
  padding: 4.5rem 0 3.5rem;
  background-image:
    linear-gradient(to bottom, rgba(15,23,42,0.85), rgba(15,23,42,0.97)),
    url("assets/lighting-hero.png");
  background-size: cover;
  background-position: center;
  color: #e5e7eb;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top, rgba(56,189,248,0.25), transparent 60%);
  mix-blend-mode: screen;
  pointer-events: none;
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 2.5rem;
  align-items: center;
}

.hero-text h1 {
  font-size: clamp(2.2rem, 3vw, 3rem);
  line-height: 1.1;
  margin-bottom: 1rem;
}

.hero-text p {
  margin-bottom: 1rem;
  max-width: 36rem;
}

.hero-highlights {
  list-style: none;
  padding: 0;
  margin: 0 0 1.25rem;
}

.hero-highlights li + li { margin-top: 0.25rem; }

.hero-note {
  font-size: 0.85rem;
  color: #cbd5f5;
}

.hero-panel { display: flex; justify-content: flex-end; }

.hero-card {
  background: rgba(15, 23, 42, 0.95);
  border-radius: 1.2rem;
  padding: 1.5rem;
  box-shadow: 0 22px 50px rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(148, 163, 184, 0.4);
}

.price-main {
  font-size: 1.8rem;
  font-weight: 700;
  display: block;
}

.price-note {
  font-size: 0.8rem;
  color: #9ca3af;
}

/* Section base */

.section {
  padding-block: 3.5rem;
  background-color: #020617;
  color: #e5e7eb;
}

.section-alt {
  background: radial-gradient(circle at top, #0b1220, #020617);
}

.section-dark {
  background: #020617;
}

.section-accent {
  background: linear-gradient(135deg, #0ea5e9, #6366f1);
  color: #f9fafb;
}

.section h2 {
  font-size: 1.8rem;
  margin-top: 0;
  margin-bottom: 0.75rem;
}

.section-intro {
  max-width: 38rem;
  margin-bottom: 2rem;
  color: #9ca3af;
}

.section-intro-light { color: #9ca3af; }

/* Section dividers */

.section-divider {
  height: 32px;
  background:
    linear-gradient(to right, transparent, rgba(15,23,42,0.9), transparent),
    repeating-linear-gradient(
      135deg,
      rgba(56,189,248,0.25),
      rgba(56,189,248,0.25) 4px,
      transparent 4px,
      transparent 8px
    );
  opacity: 0.9;
}

.section-divider-light {
  background:
    linear-gradient(to right, transparent, rgba(15,23,42,0.9), transparent),
    repeating-linear-gradient(
      45deg,
      rgba(251,191,36,0.3),
      rgba(251,191,36,0.3) 4px,
      transparent 4px,
      transparent 8px
    );
}

/* Layouts */

.two-column {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 2rem;
  align-items: flex-start;
}

.schedule-layout { align-items: stretch; }

.register-layout {
  display: grid;
  grid-template-columns: minmax(0, 2.2fr) minmax(0, 3fr);
  gap: 2rem;
  align-items: flex-start;
}

.topics-grid,
.visuals-grid,
.faq-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
}

/* Cards */

.about-card,
.topic-card,
.visual-card,
.faq-item,
.pricing-card,
.instructor-card {
  background-color: #020617;
  border-radius: 1rem;
  padding: 1.5rem;
  box-shadow: 0 12px 30px rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(148, 163, 184, 0.4);
}

/* Simple diagram frames */

.frame-mock {
  position: relative;
  border-radius: 0.8rem;
  padding: 0.75rem;
  background: radial-gradient(circle at top, rgba(15, 23, 42, 0.9), rgba(15, 23, 42, 1));
  border: 1px solid rgba(148, 163, 184, 0.5);
  height: 110px;
  overflow: hidden;
}

.frame-subject {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  width: 26px;
  height: 42px;
  border-radius: 14px;
  background: radial-gradient(circle at 30% 10%, #e5e7eb, #020617);
  box-shadow: 0 0 16px rgba(248, 250, 252, 0.7);
}

.frame-light {
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 999px;
  background: radial-gradient(circle, #fbbf24, transparent 70%);
  box-shadow: 0 0 20px rgba(251, 191, 36, 0.8);
  font-size: 0.6rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #0f172a;
}

.frame-light.key { top: 18px; left: 18px; }
.frame-light.fill { top: 38px; right: 18px; }
.frame-light.back { bottom: 10px; right: 30px; }

.frame-window-pane {
  position: absolute;
  left: 6px;
  top: 6px;
  bottom: 6px;
  width: 40%;
  background: linear-gradient(135deg, rgba(239, 246, 255, 0.25), rgba(96, 165, 250, 0.45));
  box-shadow: 0 0 22px rgba(59, 130, 246, 0.8);
  border-radius: 0.6rem;
}

.frame-bounce {
  position: absolute;
  right: 10px;
  top: 50%;
  width: 30px;
  height: 40px;
  border-radius: 0.4rem;
  border: 1px solid rgba(248, 250, 252, 0.7);
  box-shadow: -8px 0 18px rgba(248, 250, 252, 0.4);
  transform: translateY(-50%);
}

.frame-stage-line {
  position: absolute;
  bottom: 10px;
  left: 10px;
  right: 10px;
  height: 4px;
  background: linear-gradient(to right, #fbbf24, #38bdf8);
  border-radius: 999px;
}

.frame-stage-subject {
  position: absolute;
  bottom: 14px;
  left: 50%;
  transform: translateX(-50%);
  width: 28px;
  height: 32px;
  border-radius: 999px;
  background: radial-gradient(circle, #f9fafb, #0f172a);
  box-shadow: 0 0 24px rgba(248, 250, 252, 0.9);
}

.frame-stage-light {
  position: absolute;
  top: 12px;
  width: 12px;
  height: 12px;
  border-radius: 999px;
  background: radial-gradient(circle, #fde68a, transparent 70%);
  box-shadow: 0 0 26px rgba(252, 211, 77, 0.95);
}

.frame-stage-light.left { left: 16px; }
.frame-stage-light.right { right: 16px; }

/* Forms */

.form-card {
  background-color: #f9fafb;
  border-radius: 1rem;
  padding: 1.5rem;
  color: #0f172a;
  box-shadow: 0 16px 36px rgba(15, 23, 42, 0.4);
}

.form-row {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.form-group { flex: 1; min-width: 0; }

.form-group.full-width { flex-basis: 100%; }

label {
  display: block;
  font-size: 0.85rem;
  margin-bottom: 0.25rem;
  font-weight: 600;
}

input,
select,
textarea {
  width: 100%;
  padding: 0.55rem 0.7rem;
  border-radius: 0.5rem;
  border: 1px solid #cbd5f5;
  font: inherit;
  background-color: #ffffff;
}

input:focus,
select:focus,
textarea:focus {
  outline: 2px solid #0ea5e9;
  outline-offset: 1px;
  border-color: #0ea5e9;
}

textarea { resize: vertical; }

hr {
  border: none;
  border-top: 1px solid #e5e7eb;
  margin: 1rem 0 1.25rem;
}

.payment-note {
  font-size: 0.8rem;
  color: #4b5563;
}

.form-message {
  margin-top: 0.75rem;
  font-size: 0.9rem;
}

/* Footer */

.site-footer {
  background-color: #020617;
  color: #9ca3af;
  padding-block: 1.5rem;
  font-size: 0.85rem;
  border-top: 1px solid #1f2937;
}

.footer-layout {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
  justify-content: space-between;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.2rem;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #38bdf8, #6366f1);
  color: #f9fafb;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, opacity 0.15s ease;
  box-shadow: 0 10px 25px rgba(15, 23, 42, 0.75);
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 16px 30px rgba(15, 23, 42, 0.9);
  opacity: 0.96;
}

.btn-small {
  padding-inline: 0.9rem;
  padding-block: 0.4rem;
  font-size: 0.85rem;
  box-shadow: none;
}

.btn-outline {
  border: 1px solid rgba(148, 163, 184, 0.7);
  background: transparent;
  box-shadow: none;
}

.full-width { width: 100%; text-align: center; }

/* Gradient headings */

.gradient-heading {
  background: linear-gradient(135deg, #e5e7eb, #38bdf8);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.gradient-heading-light {
  background: linear-gradient(135deg, #e0f2fe, #fef3c7);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* Responsive */

@media (max-width: 900px) {
  .hero-grid,
  .two-column,
  .register-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero {
    padding-top: 4rem;
  }

  .hero-panel { justify-content: flex-start; }

  .nav-container {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  nav { flex-wrap: wrap; }
}

@media (max-width: 600px) {
  .nav-container {
    align-items: center;
  }

  nav { justify-content: center; }
}