/* ── EduCore LMS — Udemy-inspired Design System ── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
  --purple: #a435f0;
  --purple-dark: #8710d8;
  --purple-light: #f0e6ff;
  --orange: #f69c08;
  --orange-dark: #d4870a;
  --bg: #ffffff;
  --bg-soft: #f7f9fa;
  --bg-dark: #1c1d1f;
  --surface: #ffffff;
  --border: #e0e0e0;
  --border-dark: #c0c0c0;
  --text: #1c1d1f;
  --text-muted: #6a6f73;
  --text-dim: #9fa4a8;
  --success: #1e6055;
  --success-bg: #d1fae5;
  --danger: #b91c1c;
  --danger-bg: #fee2e2;
  --radius: 4px;
  --radius-md: 8px;
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.08);
  --shadow: 0 2px 12px rgba(0,0,0,0.12);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.16);
  --transition: all 0.2s ease;
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:'Inter',sans-serif;background:var(--bg);color:var(--text);line-height:1.6;min-height:100vh;display:flex;flex-direction:column}
main{flex:1}
a{color:var(--purple);text-decoration:none;transition:var(--transition)}
a:hover{color:var(--purple-dark)}
img{max-width:100%}
h1,h2,h3,h4,h5,h6{font-weight:700;line-height:1.2;color:var(--text)}
h1{font-size:clamp(1.8rem,4vw,2.8rem)}
h2{font-size:clamp(1.4rem,3vw,2rem)}
h3{font-size:1.25rem}
p{color:var(--text-muted)}

/* ── LAYOUT ── */
.container{width:100%;max-width:1200px;margin:0 auto;padding:0 2rem}
.section{padding:4rem 0}
.section-sm{padding:2.5rem 0}
.grid{display:grid;gap:1.5rem}

/* ── NAVBAR ── */
.navbar{background:#fff;border-bottom:1px solid var(--border);position:sticky;top:0;z-index:1000;padding:0}
.navbar-inner{display:flex;align-items:center;gap:1rem;height:60px}
.navbar-brand{font-size:1.5rem;font-weight:800;color:var(--purple)!important;white-space:nowrap}
.nav-search{flex:1;max-width:500px;position:relative}
.nav-search input{width:100%;padding:0.6rem 1rem 0.6rem 2.75rem;border:1px solid var(--border-dark);border-radius:99px;font-size:0.875rem;background:var(--bg-soft);font-family:inherit;outline:none;transition:var(--transition)}
.nav-search input:focus{border-color:var(--purple);box-shadow:0 0 0 2px var(--purple-light)}
.nav-search-icon{position:absolute;left:0.9rem;top:50%;transform:translateY(-50%);color:var(--text-muted);pointer-events:none}
.nav-links{display:flex;align-items:center;gap:0;list-style:none;margin-left:auto}
.nav-links a{color:var(--text);font-size:0.875rem;font-weight:500;padding:0.5rem 0.85rem;border-radius:var(--radius);transition:var(--transition);white-space:nowrap}
.nav-links a:hover{color:var(--purple)}
.nav-actions{display:flex;align-items:center;gap:0.5rem;flex-shrink:0}
.hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:0.5rem;background:none;border:none}
.hamburger span{width:22px;height:2px;background:var(--text);border-radius:2px;transition:var(--transition)}

/* Auth header toggle */
.nav-user{display:flex;align-items:center;gap:0.5rem}
.avatar-wrap{width:34px;height:34px;border-radius:50%;overflow:hidden;border:2px solid var(--purple);cursor:pointer}
.avatar-wrap img{width:100%;height:100%;object-fit:cover}
.dropdown{position:relative}
.dropdown-menu{position:absolute;top:calc(100% + 8px);right:0;background:#fff;border:1px solid var(--border);border-radius:var(--radius-md);padding:0.4rem;min-width:190px;box-shadow:var(--shadow);display:none;z-index:999}
.dropdown:hover .dropdown-menu,.dropdown.open .dropdown-menu{display:block;animation:fadeDown .15s ease}
.dropdown-menu a{display:flex;align-items:center;gap:0.6rem;padding:0.55rem 0.8rem;border-radius:var(--radius);color:var(--text-muted);font-size:0.85rem}
.dropdown-menu a:hover{background:var(--purple-light);color:var(--purple)}
.dropdown-divider{height:1px;background:var(--border);margin:0.3rem 0}
@keyframes fadeDown{from{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:translateY(0)}}

/* ── BUTTONS ── */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:0.45rem;padding:0.65rem 1.35rem;border-radius:var(--radius);font-size:0.875rem;font-weight:700;cursor:pointer;transition:var(--transition);border:2px solid transparent;text-decoration:none;white-space:nowrap;font-family:inherit;line-height:1}
.btn-primary{background:var(--purple);color:#fff;border-color:var(--purple)}
.btn-primary:hover{background:var(--purple-dark);border-color:var(--purple-dark);color:#fff}
.btn-outline-dark{background:transparent;color:var(--text);border-color:var(--text)}
.btn-outline-dark:hover{background:var(--text);color:#fff}
.btn-outline-purple{background:transparent;color:var(--purple);border-color:var(--purple)}
.btn-outline-purple:hover{background:var(--purple);color:#fff}
.btn-accent{background:var(--orange);color:#fff;border-color:var(--orange)}
.btn-accent:hover{background:var(--orange-dark);color:#fff}
.btn-sm{padding:0.4rem 0.9rem;font-size:0.8rem}
.btn-lg{padding:0.85rem 2rem;font-size:1rem}
.btn-block{width:100%}
.btn-danger{background:var(--danger);color:#fff;border-color:var(--danger)}
.btn-success{background:#059669;color:#fff;border-color:#059669}

/* ── CARDS ── */
.card{background:#fff;border:1px solid var(--border);border-radius:var(--radius-md);overflow:hidden;transition:var(--transition)}
.card:hover{box-shadow:var(--shadow-lg);transform:translateY(-2px)}
.card-img{width:100%;height:170px;object-fit:cover;display:block}
.card-body{padding:1.25rem}
.card-title{font-size:.95rem;font-weight:700;color:var(--text);margin-bottom:.35rem;line-height:1.4}
.card-text{font-size:.82rem;color:var(--text-muted)}
.card-footer{padding:.85rem 1.25rem;border-top:1px solid var(--border);display:flex;align-items:center;justify-content:space-between}

/* ── COURSE GRID ── */
.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:1.5rem}
.course-price{font-size:1.05rem;font-weight:800;color:var(--text)}
.course-price.free{color:#059669}
.course-price-original{font-size:.8rem;text-decoration:line-through;color:var(--text-dim);margin-right:.4rem}
.course-meta{display:flex;align-items:center;gap:.75rem;font-size:.75rem;color:var(--text-muted);margin-top:.4rem;flex-wrap:wrap}
.star-rating{display:flex;align-items:center;gap:.2rem;color:#e59819;font-size:.78rem}
.star-rating .score{font-weight:700;color:var(--text)}
.star-rating .count{color:var(--text-dim)}

/* ── BADGES ── */
.badge{display:inline-flex;align-items:center;padding:.2rem .55rem;border-radius:3px;font-size:.7rem;font-weight:700}
.badge-primary{background:var(--purple-light);color:var(--purple)}
.badge-success{background:#d1fae5;color:#065f46}
.badge-danger{background:#fee2e2;color:#991b1b}
.badge-warning{background:#fef3c7;color:#92400e}
.badge-dark{background:var(--bg-dark);color:#fff}
.badge-bestseller{background:#eceb98;color:#3d3c0a;font-weight:800}

/* ── PROGRESS BAR ── */
.progress-wrap{background:#e0e0e0;border-radius:99px;height:8px;overflow:hidden}
.progress-fill{height:100%;background:var(--purple);border-radius:99px;transition:width .5s ease}
.progress-label{font-size:.75rem;color:var(--text-muted);margin-top:.3rem;text-align:right}

/* ── FORMS ── */
.form-group{margin-bottom:1.25rem}
.form-label{display:block;font-size:.85rem;font-weight:600;color:var(--text);margin-bottom:.4rem}
.form-control,.form-select{width:100%;padding:.65rem .9rem;background:#fff;border:1px solid var(--border-dark);border-radius:var(--radius);color:var(--text);font-size:.9rem;font-family:inherit;transition:var(--transition);outline:none}
.form-control:focus,.form-select:focus{border-color:var(--purple);box-shadow:0 0 0 2px var(--purple-light)}
.form-control::placeholder{color:var(--text-dim)}
textarea.form-control{resize:vertical;min-height:100px}
.form-error{color:var(--danger);font-size:.78rem;margin-top:.3rem}
.form-help{color:var(--text-dim);font-size:.75rem;margin-top:.3rem}
.form-check{display:flex;align-items:center;gap:.5rem;margin-bottom:.5rem}
.form-check-input{width:16px;height:16px;accent-color:var(--purple)}

/* ── ALERTS ── */
.alert{padding:.9rem 1.1rem;border-radius:var(--radius-md);font-size:.875rem;margin-bottom:1rem;display:flex;align-items:flex-start;gap:.6rem;border-left:4px solid}
.alert-success{background:#ecfdf5;border-color:#10b981;color:#065f46}
.alert-danger{background:#fef2f2;border-color:#ef4444;color:#991b1b}
.alert-info{background:#eff6ff;border-color:#3b82f6;color:#1e40af}
.alert-warning{background:#fffbeb;border-color:#f59e0b;color:#92400e}

/* ── HERO ── */
.hero{background:var(--bg-dark);color:#fff;padding:5rem 0}
.hero h1{color:#fff;margin-bottom:1.25rem}
.hero p{color:#d1d5db;font-size:1.05rem;margin-bottom:2rem;max-width:520px}
.hero-actions{display:flex;gap:1rem;flex-wrap:wrap}
.hero-stats{display:flex;gap:2.5rem;margin-top:3rem;padding-top:2rem;border-top:1px solid rgba(255,255,255,0.1);flex-wrap:wrap}
.stat-number{font-size:2rem;font-weight:800;color:#fff;line-height:1}
.stat-label{font-size:.8rem;color:#9ca3af;margin-top:.2rem}

/* ── SECTION HEADER ── */
.section-header{margin-bottom:2.5rem}
.section-label{color:var(--purple);font-size:.75rem;font-weight:700;text-transform:uppercase;letter-spacing:.1em;margin-bottom:.5rem}
.section-header h2{margin-bottom:.5rem}
.section-header p{max-width:500px}
.section-header.center{text-align:center}
.section-header.center p{margin:0 auto}

/* ── FOOTER ── */
.footer{background:var(--bg-dark);color:#9ca3af;padding:4rem 0 2rem;margin-top:auto}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:3rem;margin-bottom:3rem}
.footer-brand{font-size:1.4rem;font-weight:800;color:#fff;margin-bottom:.75rem}
.footer-desc{font-size:.875rem;line-height:1.7}
.footer-heading{font-size:.75rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em;color:#6b7280;margin-bottom:1rem}
.footer-links{list-style:none}
.footer-links li{margin-bottom:.5rem}
.footer-links a{color:#9ca3af;font-size:.875rem}
.footer-links a:hover{color:#fff}
.footer-bottom{border-top:1px solid rgba(255,255,255,0.08);padding-top:1.5rem;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:1rem}
.footer-bottom p{font-size:.8rem;margin:0}
.social-links{display:flex;gap:.5rem}
.social-link{width:34px;height:34px;background:rgba(255,255,255,0.08);border-radius:6px;display:flex;align-items:center;justify-content:center;color:#9ca3af;font-size:.85rem;transition:var(--transition)}
.social-link:hover{background:var(--purple);color:#fff}

/* ── AUTH ── */
.auth-wrapper{min-height:100vh;display:flex;align-items:center;justify-content:center;background:var(--bg-soft);padding:2rem}
.auth-card{background:#fff;border:1px solid var(--border);border-radius:var(--radius-md);padding:2.5rem;width:100%;max-width:440px;box-shadow:var(--shadow)}
.auth-logo{text-align:center;margin-bottom:1.5rem;font-size:1.6rem;font-weight:800;color:var(--purple)}
.auth-title{font-size:1.4rem;font-weight:700;text-align:center;margin-bottom:.4rem}
.auth-subtitle{text-align:center;color:var(--text-muted);font-size:.875rem;margin-bottom:1.75rem}
.social-login-btn{display:flex;align-items:center;justify-content:center;gap:.75rem;width:100%;padding:.75rem;background:#fff;border:1px solid var(--border-dark);border-radius:var(--radius);color:var(--text);font-size:.875rem;font-weight:600;cursor:pointer;transition:var(--transition);margin-bottom:1.25rem;text-decoration:none}
.social-login-btn:hover{border-color:var(--purple);background:var(--purple-light);color:var(--purple)}
.divider{display:flex;align-items:center;gap:.85rem;margin:1.25rem 0;color:var(--text-dim);font-size:.8rem}
.divider::before,.divider::after{content:'';flex:1;height:1px;background:var(--border)}

/* ── TABLE ── */
.table{width:100%;border-collapse:collapse}
.table th{background:var(--bg-soft);padding:.65rem 1rem;font-size:.75rem;font-weight:700;text-transform:uppercase;letter-spacing:.04em;color:var(--text-muted);text-align:left;border-bottom:1px solid var(--border)}
.table td{padding:.8rem 1rem;font-size:.875rem;border-bottom:1px solid var(--border);color:var(--text-muted);vertical-align:middle}
.table tr:hover td{background:var(--bg-soft)}

/* ── DASHBOARD ── */
.dashboard-layout{display:grid;grid-template-columns:240px 1fr;min-height:calc(100vh - 60px)}
.sidebar{background:#fff;border-right:1px solid var(--border);padding:1.5rem 1rem}
.sidebar-heading{font-size:.7rem;font-weight:700;text-transform:uppercase;letter-spacing:.1em;color:var(--text-dim);padding:.5rem 1rem;margin-top:1rem}
.sidebar-nav{list-style:none}
.sidebar-nav a{display:flex;align-items:center;gap:.7rem;padding:.65rem 1rem;border-radius:var(--radius);color:var(--text-muted);font-size:.875rem;font-weight:500;transition:var(--transition)}
.sidebar-nav a:hover{background:var(--purple-light);color:var(--purple)}
.sidebar-nav a.active{background:var(--purple-light);color:var(--purple);font-weight:700}
.dashboard-content{padding:2rem;background:var(--bg-soft)}
.stat-card{background:#fff;border:1px solid var(--border);border-radius:var(--radius-md);padding:1.5rem;display:flex;align-items:center;gap:1rem}
.stat-icon{width:50px;height:50px;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:1.3rem;flex-shrink:0}
.stat-icon.purple{background:var(--purple-light)}
.stat-icon.orange{background:#fff7ed}
.stat-icon.green{background:#ecfdf5}
.stat-icon.blue{background:#eff6ff}
.stat-value{font-size:1.75rem;font-weight:800;line-height:1;color:var(--text)}
.stat-label{font-size:.75rem;color:var(--text-muted);margin-top:.2rem}

/* ── PLAYER ── */
.player-layout{display:grid;grid-template-columns:1fr 320px;height:calc(100vh - 60px)}
.player-main{overflow-y:auto;background:#000}
.player-header{background:#1c1d1f;padding:.75rem 1.5rem;display:flex;align-items:center;justify-content:space-between}
.player-header h3{color:#fff;font-size:.9rem;font-weight:600}
.player-sidebar{background:#fff;border-left:1px solid var(--border);overflow-y:auto;display:flex;flex-direction:column}
.video-wrap{background:#000;position:relative;aspect-ratio:16/9;width:100%}
.lesson-info{padding:1.5rem;background:#fff;border-bottom:1px solid var(--border)}
.lesson-info h2{font-size:1rem;margin-bottom:.5rem}
.module-header{display:flex;align-items:center;justify-content:space-between;padding:.85rem 1rem;cursor:pointer;background:var(--bg-soft);border-bottom:1px solid var(--border);font-size:.8rem;font-weight:700;color:var(--text);user-select:none}
.module-header:hover{background:#ede7f6}
.lesson-item{display:flex;align-items:flex-start;gap:.6rem;padding:.65rem 1rem .65rem 1.5rem;font-size:.8rem;color:var(--text-muted);cursor:pointer;transition:var(--transition);border-bottom:1px solid var(--border)}
.lesson-item:hover{background:var(--purple-light);color:var(--purple)}
.lesson-item.active{background:var(--purple-light);color:var(--purple);font-weight:600}
.lesson-item.completed .check-icon{color:#059669}
.check-icon{width:16px;flex-shrink:0;margin-top:2px}

.hero-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.instructor-grid { display: grid; grid-template-columns: auto 1fr; gap: 3rem; align-items: center; max-width: 800px; margin: 0 auto; }
.course-list-layout { display: grid; grid-template-columns: 240px 1fr; gap: 2rem; align-items: start; }

/* ── RESPONSIVE — Mobile First ── */

/* Tablet: ≤ 1024px */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem }
  .player-layout { grid-template-columns: 1fr; height: auto }
  .player-sidebar { display: none }
  .course-form-grid { grid-template-columns: 1fr }
  /* Admin dashboard */
  .live-preview { display: none }
}

/* Mobile: ≤ 768px */
@media (max-width: 768px) {
  /* Container padding */
  .container { padding: 0 1rem }
  .section { padding: 2.5rem 0 }

  /* Navbar */
  .nav-search { display: none }
  .nav-links { display: none }
  .auth-buttons-desktop { display: none }
  .auth-buttons-mobile { display: block !important }
  .hamburger { display: flex }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: fixed; top: 60px; left: 0; right: 0; bottom: 0;
    background: #fff; padding: 1.5rem 1rem;
    gap: .25rem; border-top: 1px solid var(--border);
    overflow-y: auto; z-index: 999;
  }
  .nav-links.open a { font-size: 1rem; padding: .85rem 1rem }
  .navbar-brand { font-size: 1.1rem }
  .navbar-brand img { height: 28px !important }

  /* Hero & Home grids */
  .hero { padding: 3rem 0 }
  .hero h1 { font-size: 1.75rem }
  .hero p { font-size: .95rem }
  .hero-stats { gap: 1.25rem; flex-wrap: wrap }
  .hero-actions { flex-direction: column }
  .hero-actions .btn { width: 100%; justify-content: center }
  .hero-grid { grid-template-columns: 1fr; gap: 2rem }
  .instructor-grid { grid-template-columns: 1fr; text-align: center; justify-items: center; gap: 1.5rem }
  .course-list-layout { grid-template-columns: 1fr }


  /* Course grid */
  .course-grid { grid-template-columns: 1fr }

  /* Student Dashboard */
  .dashboard-layout { grid-template-columns: 1fr }
  .sidebar { display: none }
  .dashboard-content { padding: 1rem }

  /* Mobile bottom nav for dashboard (replaces hidden sidebar) */
  .mobile-nav-bar {
    display: flex; position: fixed; bottom: 0; left: 0; right: 0;
    background: #fff; border-top: 1px solid var(--border);
    z-index: 990; padding: .5rem 0;
  }
  .mobile-nav-bar a {
    flex: 1; display: flex; flex-direction: column; align-items: center;
    gap: .2rem; font-size: .65rem; font-weight: 600; color: var(--text-muted);
    padding: .35rem; text-decoration: none; transition: var(--transition)
  }
  .mobile-nav-bar a i { font-size: 1.1rem }
  .mobile-nav-bar a.active, .mobile-nav-bar a:hover { color: var(--purple) }
  /* Give bottom nav space */
  .dashboard-layout { padding-bottom: 64px }

  /* Tables — horizontal scroll */
  .table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch }
  .table { min-width: 600px }

  /* Stat cards */
  .stats-grid { grid-template-columns: 1fr 1fr !important; gap: .75rem }
  .stat-card { padding: 1rem }
  .stat-value { font-size: 1.4rem }

  /* Footer */
  .footer-grid { grid-template-columns: 1fr; gap: 1.75rem }
  .footer-bottom { flex-direction: column; text-align: center }

  /* Auth */
  .auth-wrapper { padding: 1rem }
  .auth-card { padding: 1.5rem }

  /* Player — stack video + sidebar */
  .player-layout { grid-template-columns: 1fr; height: auto }
  .player-main { height: auto }
  .player-sidebar {
    display: flex; height: 400px; border-left: none;
    border-top: 1px solid var(--border)
  }

  /* Video lesson info */
  .lesson-info { padding: 1rem }
  .lesson-info h2 { font-size: .95rem }

  /* Admin dashboard layout */
  .admin-layout { grid-template-columns: 1fr !important }
  .admin-sidebar {
    position: fixed; left: -260px; top: 0; bottom: 0; width: 260px;
    z-index: 1100; transition: left .3s ease; overflow-y: auto
  }
  .admin-sidebar.open { left: 0 }
  .admin-content { margin-left: 0 !important }
  .admin-topbar { padding: .75rem 1rem }
  .admin-topbar h1 { font-size: 1rem }

  /* Course form */
  .course-form-grid { grid-template-columns: 1fr }
  .form-row-2, .form-row-3 { grid-template-columns: 1fr }
  .field-row { grid-template-columns: 1fr !important }
  .field-row.single { grid-template-columns: 1fr }
}

/* Small mobile: ≤ 480px */
@media (max-width: 480px) {
  h1 { font-size: 1.5rem }
  h2 { font-size: 1.25rem }
  .btn-lg { padding: .75rem 1.25rem; font-size: .9rem }
  .course-grid { grid-template-columns: 1fr }
  .stats-grid { grid-template-columns: 1fr !important }
  .auth-card { padding: 1.25rem }
  .hero-stats { gap: 1rem }
  .hero-stats .stat-number { font-size: 1.5rem }
  .card-img { height: 140px }
}