:root {
  --bg: #ffffff;
  --text: #111111;
  --subtle: #6b7280;
  --accent: #2563eb;
  --glass-bg: rgba(255,255,255,0.45);
  --border: rgba(255,255,255,0.25);
  --radius: 16px;
  --shadow: 0 8px 30px rgba(0,0,0,0.12);
}

body.dark {
  --bg: #05060a;
  --text: #f5f5f5;
  --subtle: #9ca3af;
  --glass-bg: rgba(15,16,24,0.6);
  --border: rgba(255,255,255,0.1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Inter", system-ui, sans-serif;
}

body {
  background: radial-gradient(circle at top, #e5e7eb 0, var(--bg) 40%);
  color: var(--text);
  transition: background .4s ease, color .4s ease;
  overflow-x: hidden;
}

/* Page transition */
.page-transition {
  opacity: 0;
  animation: fadePage .8s ease forwards;
}

@keyframes fadePage {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Loader */
#loader {
  position: fixed;
  inset: 0;
  background: #05060a;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}
.loader-logo {
  color: #fff;
  font-size: 2rem;
  letter-spacing: 0.2em;
}
.loader-bar {
  margin-top: 1rem;
  width: 160px;
  height: 4px;
  background: rgba(255,255,255,0.1);
  border-radius: 999px;
  overflow: hidden;
}
.loader-bar-fill {
  width: 0;
  height: 100%;
  background: #2563eb;
  animation: loaderFill 1.6s ease forwards;
}
@keyframes loaderFill {
  to { width: 100%; }
}

/* Particles */
#particles {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
}
@keyframes float {
  0%,100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

/* Nav */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
}
.nav-logo {
  font-weight: 700;
  letter-spacing: 0.12em;
}
.nav-links {
  list-style: none;
  display: flex;
  gap: 1rem;
}
.nav-links a {
  text-decoration: none;
  color: var(--subtle);
  padding: .3rem .7rem;
  border-radius: 999px;
  transition: .2s ease;
}
.nav-links a.active,
.nav-links a:hover {
  background: var(--accent);
  color: #fff;
}
#theme-toggle {
  padding: .4rem .8rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--glass-bg);
  backdrop-filter: blur(14px);
  cursor: pointer;
}

/* Hero */
.hero {
  position: relative;
  height: 50vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.hero-layer {
  position: absolute;
  inset: 0;
}
.hero-bg {
  background: radial-gradient(circle at top, #2563eb33, transparent 60%);
}
.hero-glow {
  background: radial-gradient(circle at bottom, #f9731633, transparent 60%);
}
.hero-content {
  position: relative;
  text-align: center;
  padding: 2rem;
  background: var(--glass-bg);
  backdrop-filter: blur(18px);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.logo-intro {
  font-size: 2.6rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  animation: logoReveal 1.4s ease forwards;
  opacity: 0;
}
.logo-intro span {
  color: var(--accent);
}
@keyframes logoReveal {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
.hero-btn {
  display: inline-block;
  margin-top: 1rem;
  padding: .6rem 1.4rem;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
}

/* Sub hero */
.sub-hero {
  text-align: center;
  padding: 2.5rem 1.5rem 1.5rem;
}

/* Filter bar */
.filter-bar {
  display: flex;
  justify-content: center;
  gap: 1rem;
  padding: 1.5rem;
}
.filter-btn {
  padding: .5rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--glass-bg);
  backdrop-filter: blur(14px);
  cursor: pointer;
  transition: .3s ease;
}
.filter-btn.active,
.filter-btn:hover {
  background: var(--accent);
  color: #fff;
}

/* Grid & cards */
.grid {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}
.video-card {
  background: var(--glass-bg);
  backdrop-filter: blur(14px);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 1rem;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(20px);
  transition: transform .25s ease, box-shadow .25s ease, opacity .4s ease;
}
.video-card:hover {
  transform: translateY(-6px) scale(1.03);
  box-shadow: 0 12px 45px rgba(0,0,0,0.18);
}
.video-wrapper {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  border-radius: var(--radius);
  overflow: hidden;
}
.video-wrapper iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: none;
}
.video-title {
  margin-top: .75rem;
  font-size: 1.1rem;
  font-weight: 600;
}
.video-meta {
  font-size: .9rem;
  color: var(--subtle);
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Page main & glass sections */
.page-main {
  max-width: 900px;
  margin: 3rem auto;
  padding: 0 1.5rem 3rem;
}
.glass-section {
  background: var(--glass-bg);
  backdrop-filter: blur(18px);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 2rem;
}
.glass-section h1 {
  margin-bottom: 1rem;
}
.glass-section p + p {
  margin-top: .5rem;
}
.contact-links p {
  margin-top: .5rem;
}
.contact-links a {
  color: var(--accent);
  text-decoration: none;
}

/* Footer */
footer {
  text-align: center;
  padding-bottom: 2rem;
  color: var(--subtle);
}