* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
}

body {
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background-color: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.navigation {
    display: flex;
    justify-content: space-around;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid #eee;
}

.navigation a {
    text-decoration: none;
    color: #555;
    padding: 5px 10px;
    border-radius: 5px;
    transition: all 0.3s;
}

.navigation a:hover {
    background-color: #f0f0f0;
}

.navigation a.active {
    color: #2c3e50;
    font-weight: bold;
    background-color: #e1f5fe;
}

.score-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding: 10px;
    background-color: #e8f5e9;
    border-radius: 5px;
}

.score {
    font-size: 18px;
    font-weight: bold;
}

.reset-btn {
    padding: 5px 10px;
    background-color: #ffcdd2;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
}

.reset-btn:hover {
    background-color: #ef9a9a;
}

.exercise-container {
    text-align: center;
    margin: 30px 0;
}

.numbers {
    font-size: 32px;
    margin-bottom: 30px;
    font-weight: bold;
}

.options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin: 0 auto;
    max-width: 400px;
}

.option {
    padding: 15px;
    font-size: 18px;
    background-color: #bbdefb;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
}

.option:hover {
    background-color: #90caf9;
}

.feedback {
    text-align: center;
    margin-top: 20px;
    min-height: 30px;
    font-weight: bold;
    font-size: 18px;
}

.correct-feedback {
    color: #2e7d32;
    animation: pulse 0.5s;
}

.wrong-feedback {
    color: #c62828;
    animation: shake 0.5s;
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20%, 60% { transform: translateX(-5px); }
    40%, 80% { transform: translateX(5px); }
}

/* Settings page styles */
.settings-form {
    max-width: 500px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.form-group input {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.save-btn {
    display: block;
    width: 100%;
    padding: 10px;
    background-color: #4caf50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    margin-top: 20px;
    transition: background-color 0.3s;
}

.save-btn:hover {
    background-color: #388e3c;
}

.success-message {
    text-align: center;
    margin-top: 10px;
    color: #2e7d32;
    font-weight: bold;
    height: 20px;
}

/* Stats page styles */
.stats-container {
    margin-top: 20px;
}

.total-stats {
    background-color: #e3f2fd;
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
}

.total-stats div {
    margin-bottom: 5px;
}

.multipliers-stats {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
}

th, td {
    padding: 8px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: #f5f5f5;
}

tr:hover {
    background-color: #f5f5f5;
}

/* Mobile styles */
@media (max-width: 600px) {
    .options {
        grid-template-columns: 1fr;
    }

    .numbers {
        font-size: 28px;
    }
}

.password-container {
    text-align: center;
    margin: 30px auto;
    max-width: 400px;
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: 8px;
}

.password-container input {
    width: 100%;
    padding: 10px;
    margin: 10px 0;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

.password-container button {
    padding: 10px 20px;
    background-color: #4caf50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
}

.password-container button:hover {
    background-color: #388e3c;
}

.password-error {
    color: #c62828;
    margin-top: 10px;
    min-height: 20px;
}

.reset-stats-btn {
    display: block;
    width: 100%;
    padding: 10px;
    background-color: #ff5722;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    margin-top: 20px;
    transition: background-color 0.3s;
}

.reset-stats-btn:hover {
    background-color: #e64a19;
}

.reset-message {
    text-align: center;
    margin-top: 10px;
    color: #2e7d32;
    font-weight: bold;
    height: 20px;
}