/* ============================================================
   i-Squill Academy — Style 3 (Modern Education / SaaS)
   Pure HTML5 + CSS3. Driven by CSS variables so the Theme
   Builder can re-skin everything (color presets, custom
   colors, 5 layout styles, light/dark) live + persisted.
   ============================================================ */

:root {
  /* Brand colors — set by the Theme Builder (js/theme.js) */
  --primary: #2563eb;
  --primary-rgb: 37 99 235;
  --primary-dark: #1d4ed8;
  --secondary: #0ea5e9;
  --secondary-rgb: 14 165 233;
  --accent: #f59e0b;
  --accent-rgb: 245 158 11;

  /* Surface / text (light scheme defaults) */
  --bg: #f7f9fc;
  --surface: #ffffff;
  --surface-2: #f1f5f9;
  --border: #e6ebf2;
  --text: #0f172a;
  --text-muted: #64748b;
  --text-soft: #94a3b8;
  --on-primary: #ffffff;

  /* Shape / depth (overridden per layout) */
  --radius: 16px;
  --radius-sm: 10px;
  --radius-lg: 24px;
  --shadow: 0 10px 30px -16px rgba(15, 23, 42, .25);
  --shadow-lg: 0 30px 60px -28px rgba(15, 23, 42, .35);
  --card-border: 1px solid var(--border);
  --ring: 0 0 0 4px rgb(var(--primary-rgb) / .14);

  /* Type */
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --display-weight: 800;
  --heading-spacing: -0.02em;

  /* Metrics (overridden per layout) */
  --container: 1180px;
  --header-h: 68px;
  --speed: .22s;
  --btn-radius: 10px;
  --card-pad: 22px;
  --section-pad: 72px;
  --uppercase: none;
}

/* ---------------- Layout templates ----------------
   Each [data-layout] re-skins shape, density, type & spacing
   so the 5 styles look clearly different.                    */
[data-layout="corporate"] {        /* tight, dense, business */
  --radius: 6px; --radius-sm: 5px; --radius-lg: 10px; --btn-radius: 5px;
  --shadow: 0 8px 20px -16px rgba(15,23,42,.35);
  --display-weight: 700; --heading-spacing: -0.01em;
  --container: 1260px; --header-h: 62px; --card-pad: 20px; --section-pad: 58px;
}
[data-layout="creative"] {         /* bold, round, playful */
  --radius: 26px; --radius-sm: 16px; --radius-lg: 36px; --btn-radius: 999px;
  --shadow: 0 28px 56px -22px rgba(99,102,241,.45);
  --display-weight: 800; --heading-spacing: -0.035em;
  --container: 1120px; --header-h: 74px; --card-pad: 28px; --section-pad: 90px;
}
[data-layout="minimal"] {          /* flat, airy, light */
  --radius: 4px; --radius-sm: 4px; --radius-lg: 8px; --btn-radius: 4px;
  --shadow: none; --card-border: 1px solid var(--border);
  --display-weight: 600; --heading-spacing: 0; --uppercase: none;
  --container: 1040px; --header-h: 66px; --card-pad: 18px; --section-pad: 96px;
}
[data-layout="premium"] {          /* refined, deep, spacious */
  --radius: 18px; --radius-sm: 12px; --radius-lg: 28px; --btn-radius: 14px;
  --shadow: 0 34px 70px -30px rgba(2,6,23,.55);
  --display-weight: 800; --heading-spacing: -0.02em;
  --container: 1160px; --header-h: 78px; --card-pad: 30px; --section-pad: 84px;
}

/* per-layout component touches */
[data-layout="corporate"] .eyebrow { border-radius: 4px; }
[data-layout="corporate"] .site-header { background: var(--surface); }
[data-layout="creative"] .course-card:hover { transform: translateY(-8px) rotate(-.6deg); }
[data-layout="creative"] .eyebrow { padding: .4rem 1rem; }
[data-layout="minimal"] .course-card:hover { transform: none; border-color: var(--primary); }
[data-layout="minimal"] .btn-primary { box-shadow: none; }
[data-layout="premium"] .card, [data-layout="premium"] .course-card { border: 1px solid color-mix(in srgb, var(--primary) 14%, var(--border)); }

/* ---------------- Dark scheme ---------------- */
[data-scheme="dark"] {
  --bg: #0b1120;
  --surface: #121a2c;
  --surface-2: #1b2538;
  --border: #243049;
  --text: #e8eef7;
  --text-muted: #93a1ba;
  --text-soft: #6b7a96;
  --shadow: 0 18px 40px -22px rgba(0,0,0,.7);
  --shadow-lg: 0 40px 80px -30px rgba(0,0,0,.8);
}

/* ---------------- Base ---------------- */
* { box-sizing: border-box; }
* { -webkit-font-smoothing: antialiased; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background var(--speed), color var(--speed);
}
h1, h2, h3, h4 { font-weight: var(--display-weight); letter-spacing: var(--heading-spacing); line-height: 1.15; margin: 0 0 .4em; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
::selection { background: rgb(var(--primary-rgb) / .2); }

.container { max-width: var(--container); margin: 0 auto; padding: 0 20px; }
.section { padding: var(--section-pad) 0; }
.muted { color: var(--text-muted); }
.soft { color: var(--text-soft); }
.center { text-align: center; }
.hidden { display: none !important; }
.gradient-text {
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.eyebrow {
  display: inline-flex; align-items: center; gap: .45rem;
  font-size: .74rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase;
  color: var(--primary); background: rgb(var(--primary-rgb) / .1);
  padding: .35rem .75rem; border-radius: 999px;
}
.section-head { max-width: 640px; margin: 0 auto 44px; text-align: center; }
.section-head h2 { font-size: clamp(1.7rem, 1.1rem + 2.4vw, 2.4rem); }
.section-head p { color: var(--text-muted); margin: 0; }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font: inherit; font-weight: 600; cursor: pointer; border: none;
  padding: .7rem 1.3rem; border-radius: var(--btn-radius);
  transition: transform var(--speed), box-shadow var(--speed), background var(--speed), color var(--speed);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--primary); color: var(--on-primary); box-shadow: 0 10px 22px -10px rgb(var(--primary-rgb) / .7); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); }
.btn-secondary { background: var(--secondary); color: #fff; }
.btn-secondary:hover { transform: translateY(-2px); filter: brightness(.96); }
.btn-outline { background: transparent; color: var(--text); border: 1px solid var(--border); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }
.btn-ghost { background: var(--surface-2); color: var(--text); }
.btn-ghost:hover { background: rgb(var(--primary-rgb) / .1); color: var(--primary); }
.btn-light { background: #fff; color: var(--primary); }
.btn-block { width: 100%; }
.btn-sm { padding: .5rem .9rem; font-size: .85rem; }
.btn-lg { padding: .95rem 1.7rem; font-size: 1.02rem; }
.btn-danger { background: #ef4444; color: #fff; }
.btn-danger:hover { background: #dc2626; }

/* ---------------- Cards ---------------- */
.card {
  background: var(--surface); border: var(--card-border);
  border-radius: var(--radius); box-shadow: var(--shadow);
}
.card-pad { padding: var(--card-pad); }
.course-card {
  background: var(--surface); border: var(--card-border); border-radius: var(--radius);
  overflow: hidden; display: flex; flex-direction: column;
  transition: transform var(--speed), box-shadow var(--speed), border-color var(--speed);
}
.course-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgb(var(--primary-rgb) / .3); }
.course-thumb { position: relative; aspect-ratio: 16/10; overflow: hidden; background: var(--surface-2); }
.course-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s; }
.course-card:hover .course-thumb img { transform: scale(1.06); }
.course-body { padding: 18px; display: flex; flex-direction: column; gap: .55rem; flex: 1; }
.course-title { font-size: 1.04rem; font-weight: 700; line-height: 1.3; }
.course-foot { margin-top: auto; display: flex; align-items: center; justify-content: space-between; padding-top: .6rem; }
.price { font-weight: 800; color: var(--primary); }
.price-free { color: #16a34a; }

/* chips / badges */
.chip {
  display: inline-flex; align-items: center; gap: .35rem;
  font-size: .72rem; font-weight: 600; padding: .25rem .6rem; border-radius: 999px;
  background: var(--surface-2); color: var(--text-muted);
}
.chip-primary { background: rgb(var(--primary-rgb) / .12); color: var(--primary); }
.chip-accent { background: rgb(var(--accent-rgb) / .15); color: var(--accent); }
.badge {
  position: absolute; top: 12px; left: 12px;
  background: rgb(0 0 0 / .6); color: #fff; backdrop-filter: blur(6px);
  font-size: .7rem; font-weight: 600; padding: .25rem .6rem; border-radius: 999px;
}
.stars { color: #f59e0b; font-size: .9rem; letter-spacing: .5px; }

.grid { display: grid; gap: 22px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

/* ---------------- Forms ---------------- */
.field { display: block; margin-bottom: 16px; }
.label { display: block; font-size: .82rem; font-weight: 600; margin-bottom: .4rem; color: var(--text); }
.input, select.input, textarea.input {
  width: 100%; font: inherit; color: var(--text); background: var(--surface);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: .7rem .85rem; transition: border-color var(--speed), box-shadow var(--speed);
}
.input:focus { outline: none; border-color: var(--primary); box-shadow: var(--ring); }
textarea.input { resize: vertical; min-height: 96px; }

/* ---------------- Header ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgb(var(--surface-rgb, 255 255 255) / .8);
  background: color-mix(in srgb, var(--surface) 86%, transparent);
  backdrop-filter: blur(12px); border-bottom: 1px solid var(--border);
}
.nav { height: var(--header-h); display: flex; align-items: center; gap: 1.4rem; }
.brand { display: inline-flex; align-items: center; gap: .55rem; font-weight: 800; font-size: 1.12rem; letter-spacing: -.02em; }
.brand-mark { width: 34px; height: 34px; border-radius: 9px; display: grid; place-items: center; color: #fff; font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--secondary)); }
.nav-links { display: flex; align-items: center; gap: 1.3rem; margin-left: .6rem; }
.nav-links a { font-size: .92rem; font-weight: 500; color: var(--text-muted); transition: color var(--speed); }
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-right { margin-left: auto; display: flex; align-items: center; gap: .8rem; }
.icon-btn { position: relative; display: grid; place-items: center; width: 40px; height: 40px; border-radius: 10px;
  background: transparent; border: none; color: var(--text); cursor: pointer; }
.icon-btn:hover { background: var(--surface-2); color: var(--primary); }
.cart-badge { position: absolute; top: 4px; right: 3px; min-width: 17px; height: 17px; padding: 0 4px;
  background: var(--accent); color: #fff; font-size: .64rem; font-weight: 700; border-radius: 999px; display: grid; place-items: center; }
.burger { display: none; }

/* mobile drawer */
.mobile-drawer { position: fixed; inset: 0 0 0 auto; width: min(320px, 86vw); background: var(--surface);
  box-shadow: var(--shadow-lg); transform: translateX(100%); transition: transform .3s; z-index: 70; padding: 20px; }
.mobile-drawer.open { transform: none; }
.mobile-backdrop { position: fixed; inset: 0; background: rgb(0 0 0 / .4); opacity: 0; pointer-events: none; transition: opacity .3s; z-index: 69; }
.mobile-backdrop.open { opacity: 1; pointer-events: auto; }
.mobile-drawer a { display: block; padding: .7rem .2rem; font-weight: 600; border-bottom: 1px solid var(--border); }

/* ---------------- Hero ---------------- */
.hero { position: relative; overflow: hidden; padding: 70px 0 80px; }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; }
.hero h1 { font-size: clamp(2.1rem, 1.2rem + 3.6vw, 3.4rem); }
.hero-blob { position: absolute; border-radius: 50%; filter: blur(70px); opacity: .5; z-index: -1; }
.hero-art { position: relative; border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow-lg); }
.stat-row { display: flex; gap: 30px; margin-top: 30px; flex-wrap: wrap; }
.stat b { font-size: 1.6rem; font-weight: 800; display: block; }

/* ---------------- Footer ---------------- */
.site-footer { background: var(--surface); border-top: 1px solid var(--border); padding: 56px 0 28px; margin-top: 40px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 32px; }
.footer-grid h4 { font-size: .9rem; margin-bottom: 1rem; }
.footer-grid a { display: block; color: var(--text-muted); font-size: .9rem; padding: .25rem 0; }
.footer-grid a:hover { color: var(--primary); }
.footer-bottom { margin-top: 36px; padding-top: 20px; border-top: 1px solid var(--border); color: var(--text-soft); font-size: .85rem;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }

/* ---------------- Toast ---------------- */
#toast-wrap { position: fixed; bottom: 22px; left: 50%; transform: translateX(-50%); z-index: 90;
  display: flex; flex-direction: column; gap: 10px; align-items: center; }
.toast { background: var(--text); color: var(--bg); padding: .8rem 1.1rem; border-radius: 12px; font-size: .9rem; font-weight: 500;
  box-shadow: var(--shadow-lg); display: flex; align-items: center; gap: .5rem; animation: toast-in .25s ease; }
.toast.success { background: #16a34a; color: #fff; }
.toast.error { background: #ef4444; color: #fff; }
.toast.info { background: var(--primary); color: #fff; }
@keyframes toast-in { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }

/* ---------------- Modal ---------------- */
.modal-backdrop { position: fixed; inset: 0; background: rgb(2 6 23 / .55); backdrop-filter: blur(3px);
  display: none; align-items: center; justify-content: center; padding: 18px; z-index: 80; }
.modal-backdrop.open { display: flex; }
.modal { background: var(--surface); border-radius: var(--radius); width: 100%; max-width: 560px; max-height: 92vh; overflow-y: auto;
  box-shadow: var(--shadow-lg); animation: modal-in .25s ease; }
@keyframes modal-in { from { opacity: 0; transform: scale(.96) translateY(10px); } to { opacity: 1; transform: none; } }
.modal-head { display: flex; align-items: center; justify-content: space-between; padding: 18px 22px; border-bottom: 1px solid var(--border); }
.modal-body { padding: 22px; }
.modal-foot { padding: 16px 22px; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 10px; }

/* ---------------- Skeleton / states ---------------- */
.skeleton { background: linear-gradient(90deg, var(--surface-2) 25%, var(--border) 37%, var(--surface-2) 63%);
  background-size: 400% 100%; animation: shimmer 1.4s ease infinite; border-radius: var(--radius-sm); }
@keyframes shimmer { 0% { background-position: 100% 0; } 100% { background-position: -100% 0; } }
.sk-card { height: 290px; border-radius: var(--radius); }
.empty-state { text-align: center; padding: 60px 20px; color: var(--text-muted); }
.empty-state .ico { font-size: 2.6rem; }
.spinner { width: 34px; height: 34px; border-radius: 50%; border: 3px solid var(--border); border-top-color: var(--primary); animation: spin .8s linear infinite; margin: 40px auto; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------------- Reveal ---------------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s, transform .6s; }
.reveal.in { opacity: 1; transform: none; }

/* ---------------- Theme Builder panel ---------------- */
.tb-toggle { position: fixed; left: 20px; bottom: 20px; z-index: 75; width: 54px; height: 54px; border-radius: 50%;
  border: none; cursor: pointer; color: #fff; font-size: 1.5rem; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--primary), var(--secondary)); box-shadow: var(--shadow-lg); transition: transform var(--speed); }
.tb-toggle:hover { transform: rotate(45deg) scale(1.06); }
.tb-panel { position: fixed; left: 20px; bottom: 86px; z-index: 76; width: 340px; max-width: calc(100vw - 40px); max-height: 80vh; overflow-y: auto;
  background: var(--surface); border: 1px solid var(--border); border-radius: 18px; box-shadow: var(--shadow-lg); padding: 18px;
  opacity: 0; transform: translateY(14px) scale(.98); pointer-events: none; transition: opacity var(--speed), transform var(--speed); }
.tb-panel.open { opacity: 1; transform: none; pointer-events: auto; }
.tb-title { font-weight: 800; font-size: 1.05rem; }
.tb-label { font-size: .72rem; text-transform: uppercase; letter-spacing: .05em; font-weight: 700; color: var(--text-soft); margin: 16px 0 8px; }
.tb-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }
.tb-opt { padding: .5rem; border: 1.5px solid var(--border); border-radius: 10px; background: var(--surface); cursor: pointer; font-size: .72rem; font-weight: 600; color: var(--text-muted); text-align: center; }
.tb-opt.active { border-color: var(--primary); color: var(--primary); box-shadow: var(--ring); }
.tb-presets { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.tb-preset { display: flex; flex-direction: column; align-items: center; gap: 5px; padding: .5rem; border: 1.5px solid var(--border); border-radius: 10px; cursor: pointer; font-size: .7rem; color: var(--text-muted); }
.tb-preset.active { border-color: var(--primary); box-shadow: var(--ring); }
.tb-dot { width: 26px; height: 26px; border-radius: 50%; border: 2px solid var(--surface); box-shadow: 0 1px 4px rgba(0,0,0,.2); }
/* layout cards (matches style-1/2 look) */
.tb-layouts { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; }
.tb-layout { text-align: left; padding: .55rem .7rem; border: 1.5px solid var(--border); border-radius: 10px; background: var(--surface); cursor: pointer; transition: border-color .15s, transform .15s; }
.tb-layout:hover { transform: translateY(-2px); }
.tb-layout.active { border-color: var(--primary); box-shadow: var(--ring); }
.tb-layout strong { display: block; font-size: .82rem; color: var(--text); }
.tb-layout small { font-size: .66rem; color: var(--text-soft); }
.tb-colors { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.tb-colors label { font-size: .72rem; font-weight: 600; color: var(--text-muted); }
.tb-colors input[type=color] { width: 100%; height: 36px; border: 1px solid var(--border); border-radius: 8px; background: none; cursor: pointer; padding: 0; }
.tb-reset { width: 100%; margin-top: 16px; padding: .6rem; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-2); color: var(--text-muted); font-weight: 600; cursor: pointer; }

/* ---------------- Admin shell ---------------- */
.admin { display: grid; grid-template-columns: 250px 1fr; min-height: 100vh; }
.admin-side { background: var(--surface); border-right: 1px solid var(--border); padding: 18px; position: sticky; top: 0; height: 100vh; overflow-y: auto; }
.admin-side .brand { margin-bottom: 22px; }
.admin-nav a { display: flex; align-items: center; gap: .7rem; padding: .65rem .8rem; border-radius: 10px; color: var(--text-muted); font-weight: 600; font-size: .92rem; margin-bottom: 3px; }
.admin-nav a:hover { background: var(--surface-2); color: var(--text); }
.admin-nav a.active { background: rgb(var(--primary-rgb) / .12); color: var(--primary); }
.admin-main { padding: 26px 30px; }
.admin-topbar { display: flex; align-items: center; justify-content: space-between; margin-bottom: 24px; gap: 12px; flex-wrap: wrap; }
.stat-cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.stat-card { background: var(--surface); border: var(--card-border); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.stat-card .n { font-size: 1.9rem; font-weight: 800; }

/* tables */
.table-wrap { background: var(--surface); border: var(--card-border); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
table.tbl { width: 100%; border-collapse: collapse; font-size: .9rem; }
.tbl th { text-align: left; font-size: .7rem; text-transform: uppercase; letter-spacing: .04em; color: var(--text-soft); padding: 12px 16px; font-weight: 700; }
.tbl td { padding: 12px 16px; border-top: 1px solid var(--border); vertical-align: middle; }
.tbl tbody tr:hover { background: var(--surface-2); }
.status { font-size: .72rem; font-weight: 700; padding: .25rem .6rem; border-radius: 999px; }
.status.Pending { background: #fef3c7; color: #b45309; }
.status.Paid { background: #dbeafe; color: #1d4ed8; }
.status.Completed { background: #dcfce7; color: #15803d; }
.status.Cancelled { background: #fee2e2; color: #b91c1c; }
.link-act { color: var(--primary); font-weight: 600; cursor: pointer; font-size: .85rem; }
.link-del { color: #ef4444; font-weight: 600; cursor: pointer; font-size: .85rem; }

/* tabs (course detail) */
.tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--border); margin-bottom: 20px; flex-wrap: wrap; }
.tab { padding: .7rem 1rem; cursor: pointer; font-weight: 600; color: var(--text-muted); border-bottom: 2px solid transparent; }
.tab.active { color: var(--primary); border-bottom-color: var(--primary); }
.acc-item { border: 1px solid var(--border); border-radius: var(--radius-sm); margin-bottom: 10px; overflow: hidden; }
.acc-head { padding: 14px 16px; font-weight: 600; cursor: pointer; display: flex; justify-content: space-between; background: var(--surface); }
.acc-body { padding: 0 16px; max-height: 0; overflow: hidden; transition: max-height .3s, padding .3s; }
.acc-item.open .acc-body { max-height: 400px; padding: 4px 16px 14px; }
.lesson { display: flex; align-items: center; gap: .6rem; padding: .45rem 0; color: var(--text-muted); font-size: .9rem; border-top: 1px dashed var(--border); }

/* filters */
.filter-bar { background: var(--surface); border: var(--card-border); border-radius: var(--radius); padding: 16px; box-shadow: var(--shadow); }
.filter-bar .field { margin-bottom: 12px; }
.range-val { font-weight: 700; color: var(--primary); }

/* qty */
.qty { display: inline-flex; align-items: center; border: 1px solid var(--border); border-radius: 999px; overflow: hidden; }
.qty button { width: 32px; height: 32px; border: none; background: var(--surface); color: var(--text-muted); cursor: pointer; font-size: 1.1rem; }
.qty button:hover { background: var(--surface-2); color: var(--primary); }
.qty span { width: 38px; text-align: center; font-weight: 700; }

/* avatar */
.avatar { width: 44px; height: 44px; border-radius: 50%; object-fit: cover; background: var(--surface-2); }

/* ---------------- Responsive ---------------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .stat-cards { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-art { order: -1; }
  .nav-links { display: none; }
  .burger { display: grid; }
  .admin { grid-template-columns: 1fr; }
  .admin-side { position: fixed; left: 0; top: 0; z-index: 60; transform: translateX(-100%); transition: transform .3s; width: 250px; }
  .admin-side.open { transform: none; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .course-detail-grid { grid-template-columns: 1fr !important; }
}
@media (max-width: 560px) {
  .grid-3, .grid-4, .grid-2 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .stat-cards { grid-template-columns: 1fr 1fr; }
  .section { padding: 48px 0; }
  .tb-panel { right: 12px; left: 12px; width: auto; }
}