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

html {
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background-color: #0f0f0f;
  color: #eaeaea;
  line-height: 1.6;
}

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

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

a:hover {
  text-decoration: underline;
}

/* ======================================================
   2. TYPOGRAPHY
====================================================== */
h1, h2, h3 {
  font-weight: 600;
  letter-spacing: 0.02em;
}

h1 { font-size: 1.25rem; }
h2 { font-size: 1.75rem; margin-bottom: 1rem; }
h3 { font-size: 1.4rem; margin-bottom: 0.5rem; }

p {
  max-width: 65ch;
  margin-bottom: 1rem;
  opacity: 0.9;
}

/* ======================================================
   3. LAYOUT HELPERS
====================================================== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

section {
  padding: 4rem 1.25rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

/* ======================================================
   4. HEADER & NAVIGATION
====================================================== */
header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: #0f0f0f;
  backdrop-filter: blur(5px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo { height: 100px; }

nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
}

nav a,
.dropdown-toggle {
  font-size: 0.95rem;
  opacity: 0.85;
  margin-left: 1.25rem;
}

nav a:hover,
.dropdown-toggle:hover {
  opacity: 1;
}

/* ======================================================
   5. HERO
====================================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  color: #fff;
  background-image: url("assets/gi-black.png");
  background-size: cover;
  background-position: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.35);
}

.hero .container {
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: 3rem;
  max-width: 600px;
  margin-bottom: 1rem;
  line-height: 1.2;
}

.hero p {
  font-size: 1.25rem;
  max-width: 500px;
}

/* ======================================================
   6. SCHEDULE
====================================================== */
.schedule-list {
  list-style: none;
  margin-top: 1.5rem;
}

.schedule-list li {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
}

/* ======================================================
   7. FOOTER
====================================================== */
footer {
  padding: 1.5rem 1.25rem;
  font-size: 0.9rem;
  opacity: 0.75;
  background-color: #0f0f0f;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.footer-left {
  font-size: 0.9rem;
  opacity: 0.75;
}

.footer-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.footer-right a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.footer-right .social-icon {
  font-size: 28px; /* Font Awesome icons */
  transition: transform 0.2s, opacity 0.2s;
}

.footer-right .social-icon:hover {
  transform: scale(1.2);
  opacity: 0.8;
}

/* ======================================================
   8. INSTRUCTOR PAGES
====================================================== */
.instructor-page {
  padding: 6rem 1.25rem 4rem; /* top padding for sticky nav */
}

.instructor-header {
  margin-bottom: 3rem;
  position: relative;
  z-index: 1;
}

.instructor-header h1 {
  font-size: 2.5rem;
}

.instructor-rank { opacity: 0.8; }

.instructor-content {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 2.5rem;
}

.instructor-photo img {
  border-radius: 4px;
}

.instructor-bio h2 {
  font-size: 1.4rem;
  margin-top: 2rem;
}

/* ======================================================
   9. ACCESSIBILITY
====================================================== */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
}

a:focus-visible,
.dropdown-toggle:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.6);
  outline-offset: 3px;
}

/* ======================================================
   10. RESPONSIVE
====================================================== */
@media (max-width: 768px) {
  .logo { height: 60px; }

  .header-inner { flex-direction: column; align-items: flex-start; }

  nav {
    margin-top: 0.75rem;
  }

  nav a,
  .dropdown-toggle {
    margin-left: 0;
    margin-right: 1rem;
    font-size: 1rem;
  }

  .hero { min-height: 80vh; }
  .hero h1 { font-size: 2rem; }
  .hero p { font-size: 1rem; }

  .instructor-content { grid-template-columns: 1fr; }
  .instructor-photo { max-width: 240px; }

  .footer-inner { flex-direction: column; text-align: center; }
  .footer-right { justify-content: center; }
}

@media (max-width: 480px) {
  .hero { min-height: 70vh; }
}