/* style.css */
:root {
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --line-height: 1.6;
    --background-color: #f9f9f9;
    --text-color: #212529;
    --primary-color: #007bff;
    --card-bg-color: #ffffff;
    --card-border-color: #e1e1e1;
    --correct-color: #28a745;
    --incorrect-color: #dc3545;
}

body {
    font-family: var(--font-family);
    line-height: var(--line-height);
    background-color: var(--background-color);
    color: var(--text-color);
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: var(--card-bg-color);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

h2 {
    color: var(--primary-color);
}

.menu {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.card {
    display: block;
    padding: 1.5rem;
    border: 1px solid var(--card-border-color);
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-color);
    transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.question-frame {
    border: 1px solid var(--card-border-color);
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.question-frame h3 {
    margin-top: 0;
}

.options label {
    display: block;
    margin-bottom: 0.75rem;
    padding: 0.75rem;
    border: 1px solid var(--card-border-color);
    border-radius: 4px;
    cursor: pointer;
}

.options input[type="radio"] {
    margin-right: 10px;
}

.btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    text-decoration: none;
}

.feedback {
    padding: 1rem;
    margin-top: 1rem;
    border-radius: 4px;
}

.feedback.correct {
    background-color: #e9f7ef;
    border-left: 5px solid var(--correct-color);
}

.feedback.incorrect {
    background-color: #fdf2f2;
    border-left: 5px solid var(--incorrect-color);
}

.feedback h4 {
    margin-top: 0;
}

#timer {
    font-size: 1.5rem;
    font-weight: bold;
    text-align: center;
    margin-bottom: 1rem;
}

.results-summary {
    margin-bottom: 2rem;
}