:root{
  --bg:#0D1117;
  --bg-secondary:#0F1419;
  --panel:#1A1D2E;
  --line:#2D3748;
  --text:#E8F0F9;
  --muted:#A0AEC0;
  --accent:#00D9FF;
  --accent-alt:#FF006E;
  --accent-light:#00F0FF;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
html,body{height:100%}

body{
  margin:0;
  background:linear-gradient(135deg, #0D1117 0%, #1A0F2E 50%, #0F1A1F 100%);
  color:var(--text);
  font:16px/1.6 -apple-system,BlinkMacSystemFont,"Segoe UI Variable","Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  display:flex;
  flex-direction:column;
}

main{
  flex:1;
}

/* NAVBAR */
.navbar{
  position:sticky;
  top:0;
  z-index:100;
  background:rgba(13,17,23,0.92);
  backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
  box-shadow:0 8px 32px rgba(0,217,255,0.08);
}

.nav-container{
  max-width:1200px;
  margin:0 auto;
  padding:16px 20px;
  display:flex;
  justify-content:space-between;
  align-items:center;
}

.nav-brand{
  display:flex;
  align-items:center;
  gap:10px;
  font-weight:700;
  font-size:22px;
  background:linear-gradient(135deg, var(--accent) 0%, var(--accent-alt) 100%);
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  background-clip:text;
  text-decoration:none;
}

.nav-logo{
  width:28px;
  height:28px;
  fill:url(#gradient-logo);
}

.nav-menu{
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  gap:32px;
}

.nav-menu a{
  color:var(--muted);
  text-decoration:none;
  font-weight:500;
  font-size:15px;
  transition:all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position:relative;
}

.nav-menu a::after{
  content:'';
  position:absolute;
  bottom:-4px;
  left:0;
  width:0;
  height:2px;
  background:linear-gradient(90deg, var(--accent), var(--accent-alt));
  transition:width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-menu a:hover{
  color:var(--accent);
}

.nav-menu a:hover::after{
  width:100%;
}

/* HERO */
.hero{
  position:relative;
  padding:100px 20px;
  text-align:center;
  overflow:hidden;
  min-height:100vh;
  display:flex;
  align-items:center;
  justify-content:center;
}

.hero-accent{
  position:absolute;
  top:-40%;
  right:-15%;
  width:700px;
  height:700px;
  background:radial-gradient(circle, rgba(0,217,255,0.12) 0%, transparent 65%);
  border-radius:50%;
  pointer-events:none;
  animation:drift 12s ease-in-out infinite;
  filter:blur(40px);
}

.hero-accent::after{
  content:'';
  position:absolute;
  bottom:20%;
  left:-30%;
  width:500px;
  height:500px;
  background:radial-gradient(circle, rgba(255,0,110,0.08) 0%, transparent 70%);
  border-radius:50%;
  animation:drift-alt 15s ease-in-out infinite;
  filter:blur(50px);
}

@keyframes drift{
  0%,100%{transform:translateX(0) translateY(0)}
  50%{transform:translateX(40px) translateY(-40px)}
}

@keyframes drift-alt{
  0%,100%{transform:translateX(0) translateY(0)}
  50%{transform:translateX(-50px) translateY(50px)}
}

.hero-content{
  position:relative;
  z-index:1;
  max-width:750px;
  animation:fadeInUp 0.8s ease-out;
}

@keyframes fadeInUp{
  from{
    opacity:0;
    transform:translateY(30px);
  }
  to{
    opacity:1;
    transform:translateY(0);
  }
}

.hero h1{
  font-size:clamp(36px,9vw,64px);
  margin:0 0 20px;
  line-height:1.15;
  letter-spacing:-0.03em;
  background:linear-gradient(135deg, var(--accent) 0%, var(--accent-alt) 50%, var(--accent) 100%);
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  background-clip:text;
  font-weight:800;
}

.hero-subtitle{
  font-size:clamp(17px,2.5vw,21px);
  color:var(--muted);
  margin:0 0 40px;
  line-height:1.5;
}

.cta-button{
  background:linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
  color:#0D1117;
  border:none;
  border-radius:8px;
  padding:18px 48px;
  font-size:18px;
  font-weight:700;
  cursor:pointer;
  transition:all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow:0 12px 48px rgba(0,217,255,0.3);
  text-transform:uppercase;
  letter-spacing:0.5px;
}

.cta-button:hover{
  transform:translateY(-4px);
  box-shadow:0 16px 56px rgba(0,217,255,0.5);
}

.cta-button:active{
  transform:translateY(-1px);
}

/* CONTAINER */
.container{
  max-width:1200px;
  margin:0 auto;
  padding:0 20px;
}

/* SKILLS SECTION */
.skills{
  padding:120px 20px;
  background:var(--bg-secondary);
  position:relative;
  overflow:hidden;
}

.skills::before{
  content:'';
  position:absolute;
  top:0;
  left:0;
  right:0;
  bottom:0;
  background:url('data:image/svg+xml,%3Csvg width="60" height="60" viewBox="0 0 60 60" xmlns="http://www.w3.org/2000/svg"%3E%3Cg fill="none" fill-rule="evenodd"%3E%3Cg fill="%2300D9FF" fill-opacity="0.03"%3E%3Cpath d="M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z"/%3E%3C/g%3E%3C/g%3E%3C/svg%3E');
  pointer-events:none;
}

.skills h2,
.contact-section h2{
  font-size:clamp(32px,7vw,48px);
  margin:0 0 16px;
  text-align:center;
  position:relative;
  z-index:1;
  background:linear-gradient(135deg, var(--accent) 0%, var(--accent-alt) 100%);
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  background-clip:text;
  font-weight:800;
}

.section-subtitle{
  text-align:center;
  color:var(--muted);
  font-size:18px;
  margin:0 0 64px;
  max-width:650px;
  margin-left:auto;
  margin-right:auto;
  position:relative;
  z-index:1;
}

.skills-grid{
  display:grid;
  grid-template-columns:repeat(auto-fit, minmax(320px, 1fr));
  gap:32px;
  margin-bottom:20px;
  position:relative;
  z-index:1;
}

.skill-card{
  background:linear-gradient(135deg, var(--panel) 0%, rgba(26,29,46,0.5) 100%);
  border:1px solid var(--line);
  border-radius:12px;
  padding:40px 28px;
  transition:all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position:relative;
  overflow:hidden;
}

.skill-card::before{
  content:'';
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:3px;
  background:linear-gradient(90deg, var(--accent) 0%, var(--accent-alt) 100%);
}

.skill-card::after{
  content:'';
  position:absolute;
  inset:0;
  background:radial-gradient(circle at 100% 0%, rgba(0,217,255,0.1) 0%, transparent 50%);
  opacity:0;
  transition:opacity 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  pointer-events:none;
}

.skill-card:hover{
  border-color:var(--accent);
  transform:translateY(-8px);
  box-shadow:0 24px 48px rgba(0,217,255,0.15);
}

.skill-card:hover::after{
  opacity:1;
}

.belt-badge{
  display:inline-block;
  padding:8px 16px;
  border-radius:6px;
  font-size:12px;
  font-weight:700;
  margin-bottom:20px;
  letter-spacing:1px;
  text-transform:uppercase;
  position:relative;
  z-index:1;
}

.white-belt .belt-badge{
  background:rgba(0,217,255,0.15);
  color:var(--accent);
  border:1px solid rgba(0,217,255,0.3);
}

.brown-belt .belt-badge{
  background:rgba(255,165,0,0.15);
  color:#FFA500;
  border:1px solid rgba(255,165,0,0.3);
}

.black-belt .belt-badge{
  background:rgba(255,0,110,0.15);
  color:var(--accent-alt);
  border:1px solid rgba(255,0,110,0.3);
}

.skill-card h3{
  font-size:26px;
  margin:0 0 16px;
  color:var(--text);
  font-weight:700;
  position:relative;
  z-index:1;
}

.skill-card p{
  color:var(--muted);
  margin:0 0 28px;
  line-height:1.8;
  position:relative;
  z-index:1;
  font-size:15px;
}

.card-points{
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  flex-direction:column;
  gap:14px;
  position:relative;
  z-index:1;
}

.card-points li{
  color:var(--muted);
  padding-left:28px;
  position:relative;
  font-size:15px;
  line-height:1.6;
}

.card-points li::before{
  content:'»';
  position:absolute;
  left:0;
  color:var(--accent);
  font-weight:bold;
  font-size:18px;
}

/* CONTACT SECTION */
.contact-section{
  padding:120px 20px;
}

.contact-form{
  max-width:520px;
  margin:48px auto 0;
  display:flex;
  flex-direction:column;
  gap:28px;
}

.form-group{
  display:flex;
  flex-direction:column;
  gap:10px;
  position:relative;
}

.form-group label{
  font-weight:600;
  color:var(--text);
  font-size:14px;
  text-transform:uppercase;
  letter-spacing:0.5px;
}

.form-group input,
.form-group textarea{
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:8px;
  padding:14px 18px;
  color:var(--text);
  font-family:inherit;
  font-size:15px;
  transition:all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.form-group input:focus,
.form-group textarea:focus{
  outline:none;
  border-color:var(--accent);
  box-shadow:0 0 0 3px rgba(0,217,255,0.1);
  background:rgba(0,217,255,0.02);
}

.form-group textarea{
  resize:vertical;
  min-height:140px;
}

.error{
  font-size:13px;
  color:#FF4757;
  min-height:18px;
  display:block;
  font-weight:500;
}

.submit-button{
  background:linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
  color:#0D1117;
  border:none;
  border-radius:8px;
  padding:16px 36px;
  font-size:16px;
  font-weight:700;
  cursor:pointer;
  transition:all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  margin-top:16px;
  text-transform:uppercase;
  letter-spacing:0.5px;
  box-shadow:0 10px 32px rgba(0,217,255,0.25);
}

.submit-button:hover{
  transform:translateY(-3px);
  box-shadow:0 14px 40px rgba(0,217,255,0.4);
}

.submit-button:disabled{
  opacity:0.6;
  cursor:not-allowed;
}

.form-status{
  text-align:center;
  padding:16px;
  border-radius:8px;
  font-size:15px;
  min-height:20px;
  font-weight:500;
}

.form-status.success{
  background:rgba(0,217,255,0.1);
  color:var(--accent);
  border:1px solid rgba(0,217,255,0.2);
}

.form-status.error{
  background:rgba(255,71,87,0.1);
  color:#FF4757;
  border:1px solid rgba(255,71,87,0.2);
}

/* CHIP (contact info fallback) */
.contact{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
  justify-content:center;
  padding:20px;
}

.chip{
  color:var(--text);
  text-decoration:none;
  border:1px solid var(--line);
  border-radius:8px;
  padding:12px 20px;
  background:var(--panel);
  font-size:15px;
  font-weight:600;
  transition:all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.chip:hover{
  border-color:var(--accent);
  color:var(--accent);
  box-shadow:0 8px 20px rgba(0,217,255,0.1);
}

/* FOOTER */
footer{
  padding:40px 16px;
  text-align:center;
  border-top:1px solid var(--line);
  background:var(--bg);
}

.ww{
  display:inline-flex;
  align-items:center;
  gap:8px;
  color:var(--muted);
  text-decoration:none;
  font-size:13px;
  transition:color 0.3s ease;
}

.ww svg{
  width:16px;
  height:16px;
  fill:var(--accent);
}

.ww strong{
  color:var(--text);
  font-weight:600;
}

.ww:hover{
  color:var(--accent);
}

/* RESPONSIVE */
@media (max-width:768px){
  .nav-menu{
    gap:20px;
  }
  .nav-menu a{
    font-size:13px;
  }
  .hero{
    padding:70px 20px;
    min-height:auto;
  }
  .skills,
  .contact-section{
    padding:70px 20px;
  }
  .skills-grid{
    gap:24px;
  }
}

/* ACCESSIBILITY */
@media (prefers-reduced-motion: reduce){
  *,*::before,*::after{
    animation-duration:0.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:0.01ms !important;
    scroll-behavior:auto !important;
  }
}

[hidden]{display:none !important}

/* LESSON & COURSE PAGES */
.breadcrumb-section {
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  padding: 16px 0;
  margin: 0;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  flex-wrap: wrap;
}

.breadcrumb a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s ease;
}

.breadcrumb a:hover {
  color: var(--accent-light);
  text-decoration: underline;
}

.breadcrumb-sep {
  color: var(--muted);
  margin: 0 4px;
}

.breadcrumb-current {
  color: var(--muted);
}

.learn-header,
.lesson-header {
  padding: 80px 20px 60px;
  text-align: center;
  background: linear-gradient(135deg, rgba(0,217,255,0.05) 0%, rgba(255,0,110,0.05) 100%);
  border-bottom: 1px solid var(--line);
}

.learn-header h1,
.lesson-header h1 {
  font-size: clamp(32px, 8vw, 54px);
  margin: 0 0 20px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-alt) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 800;
}

.learn-header .section-subtitle,
.lesson-header .section-subtitle,
.lesson-intro {
  color: var(--muted);
  font-size: 18px;
  margin: 0;
  line-height: 1.6;
}

.lesson-intro {
  max-width: 750px;
  margin: 0 auto;
}

.lesson-meta {
  display: flex;
  gap: 24px;
  justify-content: center;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.lesson-level,
.lesson-duration {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: rgba(0,217,255,0.1);
  color: var(--accent);
  border: 1px solid rgba(0,217,255,0.2);
}

.learn-paths {
  padding: 80px 20px;
  background: var(--bg);
}

.path-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 40px;
  margin-top: 40px;
}

.path-card {
  background: linear-gradient(135deg, var(--panel) 0%, rgba(26,29,46,0.5) 100%);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 40px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.path-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent) 0%, var(--accent-alt) 100%);
}

.path-card:hover {
  border-color: var(--accent);
  transform: translateY(-8px);
  box-shadow: 0 24px 48px rgba(0,217,255,0.15);
}

.path-badge {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 18px;
  letter-spacing: 1px;
  text-transform: uppercase;
  background: rgba(0,217,255,0.15);
  color: var(--accent);
  border: 1px solid rgba(0,217,255,0.3);
}

.path-card.brown .path-badge {
  background: rgba(255,165,0,0.15);
  color: #FFA500;
  border: 1px solid rgba(255,165,0,0.3);
}

.path-card.black .path-badge {
  background: rgba(255,0,110,0.15);
  color: var(--accent-alt);
  border: 1px solid rgba(255,0,110,0.3);
}

.path-card h2 {
  font-size: 28px;
  margin: 0 0 16px;
  color: var(--text);
  font-weight: 700;
}

.path-card > p:not(.coming-soon) {
  color: var(--muted);
  margin: 0 0 28px;
  line-height: 1.8;
  font-size: 15px;
}

.path-lessons {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.path-lessons li {
  margin: 0;
}

.path-lessons a {
  display: inline-block;
  color: var(--accent);
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 4px;
  transition: all 0.3s ease;
  font-weight: 500;
}

.path-lessons a:hover {
  color: var(--accent-light);
  background: rgba(0,217,255,0.1);
}

.coming-soon {
  color: var(--muted);
  font-size: 13px;
  margin: 0;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-style: italic;
}

.lesson-content {
  padding: 60px 20px;
  background: var(--bg);
  max-width: 900px;
  margin: 0 auto;
}

.lesson-section {
  margin-bottom: 50px;
}

.lesson-section h2 {
  font-size: 28px;
  margin: 0 0 20px;
  color: var(--text);
  font-weight: 700;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--line);
}

.lesson-section h3 {
  font-size: 20px;
  margin: 24px 0 16px;
  color: var(--accent);
  font-weight: 600;
}

.lesson-section p {
  color: var(--text);
  line-height: 1.8;
  margin: 0 0 16px;
  font-size: 16px;
}

.lesson-list {
  list-style: none;
  padding: 0;
  margin: 0 0 20px;
}

.lesson-list li {
  color: var(--text);
  margin: 0 0 12px;
  padding-left: 28px;
  position: relative;
  line-height: 1.7;
  font-size: 15px;
}

.lesson-list li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 18px;
  font-weight: bold;
}

.callout {
  padding: 18px 22px;
  border-radius: 8px;
  margin: 24px 0;
  border-left: 4px solid;
  background: var(--panel);
  font-size: 15px;
  line-height: 1.7;
}

.callout strong {
  color: var(--accent);
  font-weight: 700;
}

.callout.tip {
  border-left-color: var(--accent);
  background: rgba(0,217,255,0.08);
}

.callout.warning {
  border-left-color: #FFA500;
  background: rgba(255,165,0,0.08);
}

.callout.warning strong {
  color: #FFA500;
}

.code-block {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  margin: 20px 0;
  overflow-x: auto;
  position: relative;
  font-size: 14px;
  line-height: 1.6;
}

.code-block code {
  font-family: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Consolas, monospace;
  color: var(--text);
  display: block;
  white-space: pre;
  word-break: break-word;
  word-wrap: break-word;
}

.code-block .copy-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  padding: 6px 12px;
  background: var(--accent);
  color: #0D1117;
  border: none;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.code-block .copy-btn:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
}

.code-block .copy-btn:active {
  transform: translateY(0);
}

.lesson-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  background: var(--panel);
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--line);
}

.lesson-table th {
  background: rgba(0,217,255,0.1);
  color: var(--accent);
  padding: 14px 16px;
  text-align: left;
  font-weight: 700;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-bottom: 1px solid var(--line);
}

.lesson-table td {
  padding: 14px 16px;
  color: var(--text);
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.lesson-table tr:last-child td {
  border-bottom: none;
}

.lesson-table tr:hover {
  background: rgba(0,217,255,0.05);
}

.lesson-nav {
  padding: 60px 20px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--line);
}

.nav-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 900px;
  margin: 0 auto;
  flex-wrap: wrap;
  gap: 24px;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  padding: 10px 16px;
  border-radius: 6px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  font-size: 15px;
}

.nav-link:hover {
  color: var(--accent-light);
  background: rgba(0,217,255,0.1);
}

.nav-link.prev::before {
  content: '←';
}

.nav-link.next::after {
  content: '→';
}

@media (max-width: 768px) {
  .learn-header,
  .lesson-header {
    padding: 50px 20px 40px;
  }

  .learn-header h1,
  .lesson-header h1 {
    font-size: clamp(28px, 6vw, 42px);
  }

  .path-grid {
    gap: 24px;
    grid-template-columns: 1fr;
  }

  .lesson-content {
    padding: 40px 20px;
  }

  .nav-footer {
    flex-direction: column;
    align-items: stretch;
  }

  .nav-link {
    text-align: center;
    justify-content: center;
  }

  .lesson-meta {
    gap: 12px;
  }

  .code-block .copy-btn {
    top: 8px;
    right: 8px;
    padding: 4px 10px;
    font-size: 11px;
  }
}