:root{--bg:#f6f7fb;--ink:#172033;--muted:#667085;--card:#fff;--brand:#f28c00;--brand2:#d97706;--line:#e7e9f0;--ok:#16a34a;--lock:#94a3b8;--dark:#0f172a;--blue:#2563eb;--purple:#7c3aed}*{box-sizing:border-box}body{margin:0;font-family:Inter,system-ui,-apple-system,Segoe UI,Arial,sans-serif;background:linear-gradient(180deg,#fff7ed 0,#f6f7fb 260px);color:var(--ink)}a{text-decoration:none;color:inherit}.wrap{max-width:1180px;margin:0 auto;padding:24px}.top{display:flex;justify-content:space-between;align-items:center;margin-bottom:22px}.brand{display:flex;gap:12px;align-items:center}.logo{width:46px;height:46px;border-radius:16px;background:linear-gradient(135deg,var(--brand),var(--brand2));display:grid;place-items:center;color:#fff;font-weight:900;box-shadow:0 12px 30px rgba(242,140,0,.25)}.brand h1{font-size:21px;margin:0}.brand p{margin:2px 0 0;color:var(--muted);font-size:13px}.nav{display:flex;gap:10px;flex-wrap:wrap}.btn{border:0;border-radius:14px;padding:11px 15px;background:#111827;color:#fff;font-weight:700;cursor:pointer;display:inline-block}.btn.light{background:#fff;color:#111827;border:1px solid var(--line)}.btn.orange{background:linear-gradient(135deg,var(--brand),var(--brand2))}.btn.disabled{background:#cbd5e1;cursor:not-allowed}.hero{background:rgba(255,255,255,.88);backdrop-filter:blur(12px);border:1px solid rgba(255,255,255,.9);border-radius:28px;padding:28px;box-shadow:0 20px 60px rgba(15,23,42,.08);margin-bottom:22px}.hero h2{font-size:34px;letter-spacing:-.04em;margin:0 0 8px}.hero p{color:var(--muted);line-height:1.55}.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}.grid.two{grid-template-columns:1fr 1fr}.card{background:var(--card);border:1px solid var(--line);border-radius:24px;padding:20px;box-shadow:0 12px 34px rgba(15,23,42,.05)}.module-card{transition:.2s}.module-card:hover{transform:translateY(-2px);box-shadow:0 18px 44px rgba(15,23,42,.08)}.small{font-size:13px;color:var(--muted)}.progress{height:12px;background:#e5e7eb;border-radius:99px;overflow:hidden}.bar{height:100%;background:linear-gradient(90deg,var(--brand),var(--purple));border-radius:99px}.pill{display:inline-flex;align-items:center;gap:6px;border-radius:999px;padding:6px 10px;font-size:12px;font-weight:800}.pill.ok{background:#dcfce7;color:#166534}.pill.lock{background:#f1f5f9;color:#475569}.pill.now{background:#ffedd5;color:#9a3412}.lesson-list{display:grid;gap:12px}.lesson-row{display:flex;justify-content:space-between;gap:12px;align-items:center;border:1px solid var(--line);border-radius:18px;padding:14px 16px;background:#fff}.lesson-row.locked{opacity:.62;background:#f8fafc}.lesson-page{display:grid;grid-template-columns:260px 1fr;gap:18px}.side{position:sticky;top:16px;align-self:start}.box{border-radius:22px;padding:18px;margin:14px 0;border:1px solid var(--line);background:#fff}.box h3{margin:0 0 9px}.coach{background:#eff6ff;border-color:#bfdbfe}.mistake{background:#fff1f2;border-color:#fecdd3}.why{background:#f0fdf4;border-color:#bbf7d0}.think{background:#faf5ff;border-color:#ddd6fe}.challenge{background:#fffbeb;border-color:#fde68a}.quiz-option{display:block;padding:12px 14px;border:1px solid var(--line);border-radius:14px;margin:8px 0;background:#fff;cursor:pointer}.textarea{width:100%;min-height:120px;border:1px solid var(--line);border-radius:16px;padding:14px;font:inherit}.footer{color:var(--muted);font-size:12px;margin:28px 0}@media(max-width:900px){.grid,.grid.two{grid-template-columns:1fr}.lesson-page{grid-template-columns:1fr}.top{align-items:flex-start;gap:12px;flex-direction:column}.hero h2{font-size:27px}}
.brand-logo{width:82px;height:auto;object-fit:contain;filter:drop-shadow(0 10px 18px rgba(15,23,42,.16))}.glossary-toolbar{display:flex;gap:10px;flex-wrap:wrap;align-items:center}.search-input,.select-input{border:1px solid var(--line);border-radius:14px;padding:12px 14px;font:inherit;background:#fff}.search-input{min-width:280px;flex:1}.term-card{position:relative}.term-head{display:flex;justify-content:space-between;gap:10px;align-items:flex-start}.term-en{font-size:20px;font-weight:900;margin:0}.term-gr{color:var(--brand2);font-weight:800;margin:4px 0 8px}.category-tag{display:inline-flex;border-radius:999px;padding:5px 9px;background:#f1f5f9;color:#475569;font-size:12px;font-weight:800}.favorite-btn{border:0;background:#fff7ed;border:1px solid #fed7aa;color:#9a3412;border-radius:999px;padding:7px 10px;font-weight:900;cursor:pointer}.favorite-btn.on{background:#ffedd5;color:#c2410c}.review-card{max-width:760px;margin:0 auto}.flashcard{font-size:30px;font-weight:900;letter-spacing:-.03em;text-align:center;padding:40px 20px}.answer-block{background:#f8fafc;border:1px solid var(--line);border-radius:20px;padding:18px;margin:14px 0}.difficulty-buttons{display:flex;gap:10px;flex-wrap:wrap}.btn.again{background:#ef4444}.btn.hard{background:#f97316}.btn.good{background:#16a34a}.btn.easy{background:#2563eb}.stat-row{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:18px}.mini-stat{background:#fff;border:1px solid var(--line);border-radius:20px;padding:16px}.mini-stat b{font-size:24px}.related-terms{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}.related-terms a{background:#eef2ff;color:#3730a3;border-radius:999px;padding:6px 10px;font-size:12px;font-weight:800}@media(max-width:700px){.brand-logo{width:70px}.stat-row{grid-template-columns:1fr 1fr}.search-input{min-width:100%}}

.brand-logo{width:74px;height:42px;object-fit:contain;display:block;filter:drop-shadow(0 8px 18px rgba(14,165,233,.18))}.top{align-items:center}.toolbar{display:flex;gap:10px;align-items:center;flex-wrap:wrap}.search,.toolbar input,.toolbar select{background:#0b1224;border:1px solid rgba(148,163,184,.25);color:#e2e8f0;border-radius:14px;padding:12px 14px;min-width:240px}.inline{display:flex;gap:6px;align-items:center}.stats{display:flex;gap:10px;flex-wrap:wrap;margin-top:16px}.stats span{background:rgba(15,23,42,.7);border:1px solid rgba(148,163,184,.18);padding:9px 12px;border-radius:999px}.glossary-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.term-card h3{margin:8px 0 2px}.greek{font-size:18px;font-weight:800;color:#e0f2fe}.term-head{display:flex;justify-content:space-between;gap:12px}.star{font-size:28px;background:transparent;border:0;color:#fbbf24;cursor:pointer}.difficulty{display:flex;gap:8px;align-items:center;flex-wrap:wrap;margin-top:12px}.chip{border:1px solid rgba(148,163,184,.25);background:#111827;color:#cbd5e1;border-radius:999px;padding:7px 10px;cursor:pointer}.chip.active{background:#0ea5e9;color:#fff;border-color:#38bdf8}.review-actions{display:flex;gap:10px;margin-top:16px}.term-mini-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.term-mini{display:block;padding:12px;border-radius:16px;background:rgba(15,23,42,.72);border:1px solid rgba(148,163,184,.18);text-decoration:none;color:#e2e8f0}.term-mini span{display:block;color:#93c5fd;font-size:13px;margin-top:3px}@media(max-width:780px){.glossary-grid,.term-mini-grid{grid-template-columns:1fr}.brand-logo{width:58px;height:34px}.toolbar input,.toolbar select{min-width:100%;width:100%}}

/* V5 light-theme overrides */
.search,.toolbar input,.toolbar select{background:#fff;color:var(--ink);border:1px solid var(--line)}.greek{color:var(--brand2)}.stats span{background:#fff;color:var(--ink);border:1px solid var(--line)}.term-mini{background:#f8fafc;color:var(--ink);border:1px solid var(--line)}.term-mini span{color:var(--brand2)}


.video-box{border:1px solid rgba(56,189,248,.22);background:linear-gradient(135deg,rgba(14,165,233,.12),rgba(15,23,42,.92));}
.video-wrap{position:relative;width:100%;padding-top:56.25%;border-radius:18px;overflow:hidden;background:#020617;border:1px solid rgba(148,163,184,.18);box-shadow:0 18px 45px rgba(2,6,23,.24);}
.video-wrap iframe{position:absolute;inset:0;width:100%;height:100%;}
.term-video{margin:12px 0;padding:10px 12px;border-radius:14px;background:rgba(15,23,42,.06);border:1px solid rgba(148,163,184,.16);}
.term-video summary{cursor:pointer;font-weight:800;color:#0f172a;}
.small-video{margin-top:10px;border-radius:12px;}


/* =========================
   V7 FULL PREMIUM BRANDING
========================= */
.premium-top{
  padding:18px 20px;
  border:1px solid rgba(255,255,255,.85);
  background:linear-gradient(135deg,rgba(255,255,255,.92),rgba(255,247,237,.84));
  border-radius:30px;
  box-shadow:0 24px 70px rgba(15,23,42,.10);
  backdrop-filter:blur(14px);
}
.premium-brand{
  gap:18px;
}
.brand-logo-shell{
  width:104px;
  height:72px;
  border-radius:24px;
  background:linear-gradient(135deg,#0f172a,#1e293b);
  display:flex;
  align-items:center;
  justify-content:center;
  box-shadow:0 18px 48px rgba(15,23,42,.25), inset 0 1px 0 rgba(255,255,255,.12);
  overflow:hidden;
  position:relative;
}
.brand-logo-shell:after{
  content:"";
  position:absolute;
  inset:-40%;
  background:radial-gradient(circle at 30% 20%,rgba(242,140,0,.32),transparent 38%),
             radial-gradient(circle at 80% 80%,rgba(37,99,235,.28),transparent 40%);
  pointer-events:none;
}
.brand-logo{
  max-width:94px;
  max-height:62px;
  object-fit:contain;
  position:relative;
  z-index:2;
  filter:drop-shadow(0 10px 18px rgba(0,0,0,.34));
}
.brand-copy h1{
  font-size:34px;
  line-height:1;
  letter-spacing:-.06em;
  margin:0;
  background:linear-gradient(135deg,#111827,#334155 45%,#f28c00);
  -webkit-background-clip:text;
  background-clip:text;
  color:transparent;
}
.brand-copy p{
  font-size:14px;
  color:#64748b;
  margin:7px 0 0;
  font-weight:700;
}
.video-wrap{
  position:relative;
  width:100%;
  padding-top:56.25%;
  border-radius:22px;
  overflow:hidden;
  background:#0f172a;
  box-shadow:0 18px 50px rgba(15,23,42,.18);
  border:1px solid rgba(255,255,255,.12);
}
.video-wrap iframe{
  position:absolute;
  inset:0;
  width:100%;
  height:100%;
}
.term-video summary{
  cursor:pointer;
  font-weight:900;
  color:#0f172a;
  padding:10px 0;
}
.small-video{
  border-radius:18px;
  margin-top:8px;
}
@media(max-width:760px){
  .premium-top{align-items:flex-start}
  .brand-logo-shell{width:86px;height:62px;border-radius:20px}
  .brand-logo{max-width:78px;max-height:52px}
  .brand-copy h1{font-size:28px}
}

/* =========================
   V8 INTELLIGENT SYSTEM
========================= */
.ai-feedback{
  background:linear-gradient(135deg,#eef2ff,#fdf2f8);
  border-color:#c7d2fe;
}
.ai-feedback pre{
  white-space:pre-wrap;
  font-family:inherit;
  line-height:1.55;
  margin:0;
}
.answer{
  width:100%;
  border:1px solid var(--line);
  border-radius:18px;
  padding:16px;
  font-family:inherit;
  font-size:15px;
  margin:10px 0 14px;
  background:#fff;
}
.selected{
  outline:3px solid rgba(242,140,0,.28);
  box-shadow:0 18px 54px rgba(242,140,0,.16);
}
.stats{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:14px;
}
.stats span{
  border:1px solid var(--line);
  background:#fff;
  border-radius:999px;
  padding:8px 12px;
  font-weight:800;
  font-size:13px;
}