:root {
    --primary: #007bff;
    --success: #28a745;
    --danger: #dc3545;
    --warning: #ffc107;
    --secondary: #6c757d;
    --bg: #f4f4f9;
    --card-bg: #ffffff;
    --text: #333;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    margin: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
    box-sizing: border-box;
}

h1 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    text-align: center;
    color: #444;
}

.card {
    background: var(--card-bg);
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    width: 100%;
    margin-bottom: 20px;
    box-sizing: border-box;
}

.label {
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 5px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.question {
    font-size: 1.6rem;
    font-weight: bold;
    margin-bottom: 20px;
    color: #222;
}

input[type="text"] {
    width: 100%;
    padding: 12px;
    font-size: 1.1rem;
    border: 2px solid #ddd;
    border-radius: 8px;
    outline: none;
    transition: border-color 0.2s;
    box-sizing: border-box;
}

input[type="text"]:focus {
    border-color: var(--primary);
}

.action-btn {
    width: 100%;
    padding: 14px;
    font-size: 1rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    background: var(--success);
    color: white;
    font-weight: bold;
    transition: background 0.2s, transform 0.1s;
    margin-bottom: 10px;
}

.action-btn:active { transform: scale(0.98); }
.action-btn.primary { background: var(--primary); }
.action-btn.secondary { background: var(--secondary); }
.action-btn.danger { background: var(--danger); }

.mode-select {
    display: flex;
    flex-direction: column; /* Buttons untereinander auf Mobile */
    gap: 10px;
    margin-bottom: 20px;
    width: 100%;
}

.mode-select button {
    padding: 10px;
    border: 2px solid #ddd;
    background: white;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    color: #555;
    flex: 1;
}

.mode-select button.active {
    border-color: var(--primary);
    background: #e3f2fd;
    color: var(--primary);
}

/* --- OVERLAY (WICHTIG!) --- */
.overlay {
    display: none; /* Standardmäßig unsichtbar */
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
}

.overlay-content {
    background: white;
    padding: 20px;
    border-radius: 12px;
    width: 100%;
    max-width: 400px;
    max-height: 80vh;
    display: flex;
    flex-direction: column;
}

.page-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(70px, 1fr));
    gap: 10px;
    margin: 20px 0;
    overflow-y: auto;
    flex: 1;
}

.page-item { position: relative; }

.page-item input[type="checkbox"] {
    position: absolute;
    opacity: 0;
    width: 100%;
    height: 100%;
    cursor: pointer;
}

.page-item label {
    display: block;
    padding: 10px;
    background: #f0f0f0;
    border-radius: 6px;
    text-align: center;
    font-weight: bold;
    color: #555;
    border: 2px solid transparent;
    transition: all 0.2s;
}

.page-item input:checked + label {
    background: #e3f2fd;
    border-color: var(--primary);
    color: var(--primary);
}

/* FEEDBACK MESSAGES */
#feedback-msg { margin-top: 15px; font-weight: bold; }
.msg-correct { color: var(--success); }
.msg-wrong { color: var(--danger); }
.msg-typo { color: var(--warning); }

.progress-container {
    background: #fff;
    border-top: 1px solid #eee;
    padding: 15px 20px;
    width: 100%;
    box-sizing: border-box;
    position: sticky;
    bottom: 0;
}

.progress-text {
    text-align: center;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: #666;
}

.progress-bar-bg {
    width: 100%;
    height: 8px;
    background: #eee;
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    width: 0%;
    background: var(--success);
    transition: width 0.3s ease, background-color 0.3s;
}