* { box-sizing: border-box; }
body { margin: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
       color: #1a1a1a; background: #f7f7f8; line-height: 1.5; }
.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }
.topbar { background: #1a3a5c; color: #fff; padding: 14px 0; margin-bottom: 24px; }
.topbar .container { display: flex; justify-content: space-between; align-items: center; }
.brand { color: #fff; text-decoration: none; font-weight: 600; font-size: 18px; }
.user { font-size: 14px; color: #cfd8e3; }
.user code { color: #fff; background: rgba(255,255,255,.1); padding: 2px 6px; border-radius: 4px; }

h1 { margin: 0 0 12px; font-size: 26px; }
h2 { margin: 24px 0 12px; font-size: 20px; }
.muted { color: #6b7280; font-size: 14px; }
.ok { color: #15803d; }
.fail { color: #b91c1c; }

.card { background: #fff; padding: 24px; border-radius: 12px; margin-bottom: 20px;
        box-shadow: 0 1px 3px rgba(0,0,0,.06); }
.card.narrow { max-width: 420px; margin: 40px auto; }

.btn { display: inline-block; padding: 10px 18px; background: #1a3a5c; color: #fff;
       border: none; border-radius: 8px; cursor: pointer; text-decoration: none;
       font-size: 15px; font-weight: 500; }
.btn:hover { background: #143049; }
.btn-secondary { background: #e5e7eb; color: #1a1a1a; }
.btn-secondary:hover { background: #d1d5db; }
.btn-link { background: none; border: none; color: #1a3a5c; cursor: pointer; padding: 4px 8px; font-size: 14px; }
.back { display: inline-block; margin-bottom: 16px; color: #6b7280; text-decoration: none; }
.back:hover { color: #1a3a5c; }

.grade-title { margin-top: 28px; color: #1a3a5c; }
.lessons { display: flex; flex-direction: column; gap: 8px; margin-bottom: 16px; }
.lesson-row { display: grid; grid-template-columns: 80px 1fr auto auto; gap: 16px;
              align-items: center; padding: 14px 18px; background: #fff;
              border-radius: 10px; box-shadow: 0 1px 2px rgba(0,0,0,.04); }
.lesson-row.locked { opacity: 0.55; }
.lesson-num { color: #6b7280; font-size: 13px; }
.lesson-title { font-weight: 500; }
.badge { display: inline-block; padding: 3px 10px; border-radius: 12px; font-size: 12px; font-weight: 500; }
.badge.ok { background: #dcfce7; color: #15803d; }
.badge.wip { background: #dbeafe; color: #1e40af; }
.badge.lock { background: #f3f4f6; color: #6b7280; }
.badge.fail { background: #fee2e2; color: #b91c1c; }
.lesson-actions .btn { padding: 6px 12px; font-size: 13px; margin-left: 6px; }

.player-wrap { position: relative; background: #000; border-radius: 12px;
               overflow: hidden; max-width: 960px; margin: 16px auto 0; }
#video { width: 100%; display: block; max-height: 70vh; }
.watermark { position: absolute; top: 20px; left: 20px; color: rgba(255,255,255,.45);
             font-size: 14px; font-weight: 500; text-shadow: 0 1px 2px rgba(0,0,0,.6);
             pointer-events: none; user-select: none; transition: top 1.2s, left 1.2s; }

.test-form .question { padding: 16px 0; border-bottom: 1px solid #e5e7eb; }
.test-form .q-text { margin-bottom: 12px; }
.test-form .ans { display: block; padding: 8px 0; cursor: pointer; }
.test-form .ans input { margin-right: 10px; }

.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 16px; }
.form-grid label { display: flex; flex-direction: column; font-size: 13px; color: #6b7280; }
.form-grid input, .form-grid select { padding: 8px 10px; border: 1px solid #d1d5db;
                                       border-radius: 6px; font-size: 15px; color: #1a1a1a; }
.form-grid button { grid-column: span 2; }

.emp-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: 10px;
             overflow: hidden; box-shadow: 0 1px 3px rgba(0,0,0,.06); }
.emp-table th, .emp-table td { padding: 10px 14px; text-align: left; border-bottom: 1px solid #f1f5f9; font-size: 14px; }
.emp-table th { background: #f8fafc; font-weight: 600; color: #475569; font-size: 13px; }
.emp-table tr.inactive { opacity: 0.5; }
.emp-table code { font-size: 12px; background: #f1f5f9; padding: 2px 6px; border-radius: 4px; }
.emp-table a { color: #1a3a5c; }
.link-box { width: 100%; padding: 4px 6px; font-size: 11px; border: 1px solid #e5e7eb;
            border-radius: 4px; font-family: monospace; }

@media (max-width: 700px) {
    .lesson-row { grid-template-columns: 1fr; gap: 8px; }
    .form-grid { grid-template-columns: 1fr; }
    .form-grid button { grid-column: span 1; }
}