:root {
    --primary: #2f6fed;
    --primary-dark: #1f4fbb;
    --correct: #1b6fd6;
    --wrong: #d63b3b;
    --bg: #f5f7fb;
    --card: #ffffff;
    --border: #e2e6ee;
    --text: #222833;
    --muted: #6b7383;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.55;
}

.wrap {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 20px;
}

.site-header {
    background: var(--card);
    border-bottom: 1px solid var(--border);
    padding: 14px 0;
}
.site-header .wrap { display: flex; justify-content: space-between; align-items: center; }
.site-header h1 { margin: 0; font-size: 1.4rem; }
.site-header .accent { color: var(--primary); }

.user-nav { display: flex; gap: 14px; align-items: center; font-size: 0.9rem; }
.user-nav #usernameLabel { color: var(--muted); }

.link-btn {
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
    font-size: 0.9rem;
    padding: 4px 6px;
}
.link-btn:hover { text-decoration: underline; }

main#app { padding: 30px 20px 60px; min-height: 60vh; }

.site-footer {
    text-align: center;
    color: var(--muted);
    font-size: 0.85rem;
    padding: 20px 0 40px;
}

/* ---- Cards / layout ---- */
.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 24px;
    margin-bottom: 20px;
}

h2 { margin-top: 0; }

.btn {
    display: inline-block;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 6px;
    padding: 10px 20px;
    font-size: 0.95rem;
    cursor: pointer;
    margin-top: 14px;
}
.btn:hover { background: var(--primary-dark); }
.btn.secondary { background: #fff; color: var(--primary); border: 1px solid var(--primary); }
.btn.secondary:hover { background: #eef3fe; }
.btn.danger { background: #fff; color: var(--wrong); border: 1px solid var(--wrong); }
.btn.danger:hover { background: #fdeeee; }
.btn:disabled { opacity: 0.5; cursor: default; }

/* ---- Auth ---- */
.auth-form { max-width: 360px; margin: 40px auto; }
.auth-form input {
    width: 100%;
    padding: 10px 12px;
    margin-bottom: 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 1rem;
}
.auth-error { color: var(--wrong); font-size: 0.9rem; margin-bottom: 10px; }
.auth-switch { margin-top: 14px; font-size: 0.9rem; color: var(--muted); }
.auth-switch a { color: var(--primary); cursor: pointer; }

/* ---- Levels grid ---- */
.levels-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 16px;
}
.level-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 18px;
}
.level-card h3 { margin: 0 0 6px; }
.level-card .progress-bar {
    background: #edf1f8;
    border-radius: 5px;
    height: 8px;
    margin: 10px 0;
    overflow: hidden;
}
.level-card .progress-bar-fill {
    background: var(--primary);
    height: 100%;
}
.level-card .meta { font-size: 0.85rem; color: var(--muted); }
.level-card .actions { display: flex; gap: 8px; margin-top: 12px; }
.badge-done {
    display: inline-block;
    background: #e8f7ee;
    color: #1f9d55;
    font-size: 0.78rem;
    padding: 2px 8px;
    border-radius: 20px;
    margin-left: 6px;
}

/* ---- Text display ---- */
.text-title { font-size: 1.3rem; margin-bottom: 4px; }
.text-progress { color: var(--muted); font-size: 0.9rem; margin-bottom: 18px; }
.text-body { font-size: 1.05rem; }
.text-body p { margin: 0 0 14px; }

.filled-word {
    background: #eef3fe;
    color: var(--primary-dark);
    padding: 1px 6px;
    border-radius: 4px;
    font-weight: 600;
}

.blank-input {
    border: none;
    border-bottom: 2px solid var(--primary);
    background: #f3f6fd;
    font-size: 1rem;
    padding: 2px 6px;
    margin: 0 2px;
    border-radius: 3px;
    text-align: center;
}
.blank-input:focus { outline: none; border-bottom-color: var(--primary-dark); background: #e8effd; }

.answer-correct {
    color: var(--correct);
    font-weight: 600;
    padding: 1px 4px;
}
.answer-wrong {
    color: var(--wrong);
    font-weight: 600;
    padding: 1px 4px;
}
.answer-wrong .correct-hint {
    color: var(--wrong);
    font-style: normal;
    font-weight: 400;
    font-size: 0.9em;
}

.score-box {
    margin: 20px 0;
    padding: 16px;
    border-radius: 8px;
    text-align: center;
    font-size: 1.1rem;
}
.score-box.success { background: #e8f7ee; color: #1f9d55; }
.score-box.warning { background: #fdeeee; color: var(--wrong); }
.score-box .score-value { font-size: 2rem; font-weight: 700; display: block; }

.correction-block {
    margin-top: 24px;
    padding-top: 18px;
    border-top: 1px dashed var(--border);
}
.correction-block h3 { color: var(--muted); font-size: 0.95rem; text-transform: uppercase; letter-spacing: 0.03em; }

.level-complete {
    text-align: center;
    padding: 40px 20px;
}

/* ---- Stats ---- */
.stats-table { width: 100%; border-collapse: collapse; margin-top: 10px; }
.stats-table th, .stats-table td {
    text-align: left;
    padding: 10px 8px;
    border-bottom: 1px solid var(--border);
    font-size: 0.92rem;
}
.stats-summary {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}
.stats-summary .stat-pill {
    background: #eef3fe;
    color: var(--primary-dark);
    padding: 10px 18px;
    border-radius: 8px;
    font-size: 0.9rem;
}
.stats-summary .stat-pill b { display: block; font-size: 1.3rem; }

.loading { text-align: center; color: var(--muted); padding: 40px; }