@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;700&display=swap');

:root {
    --bg-color: #1a1a1a;
    --text-color: #e0e0e0;
    --main-color: #4a4a4a;
    --accent-color: #00aaff;
    --correct-color: #4caf50;
    --incorrect-color: #f44336;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    text-align: center;
    padding: 1rem;
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--accent-color);
}

h2 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
}

.screen {
    display: none;
    width: 100%;
    max-width: 800px;
    padding: 2rem;
    background-color: var(--main-color);
    border-radius: 15px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
}

.screen.active {
    display: block;
}

.mode-selection {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
}

.mode {
    background-color: rgba(0,0,0,0.2);
    padding: 2rem;
    border-radius: 10px;
    flex: 1;
    min-width: 250px;
    transition: transform 0.3s, box-shadow 0.3s;
}

.mode:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 170, 255, 0.2);
}

.start-btn, #retry-btn {
    background-color: var(--accent-color);
    color: #ffffff;
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
    font-weight: bold;
}

.start-btn:hover, #retry-btn:hover {
    background-color: #0088cc;
    transform: scale(1.05);
}

#quiz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    font-size: 1.2rem;
    font-weight: bold;
}

#timer {
    background-color: var(--accent-color);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
}

#question-area {
    margin-bottom: 2rem;
}

#question {
    font-size: 5rem;
    font-weight: bold;
    margin: 0;
    line-height: 1.2;
}

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

.option {
    background-color: rgba(255,255,255,0.1);
    border: 2px solid transparent;
    color: var(--text-color);
    padding: 1.5rem;
    font-size: 1.8rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s, border-color 0.3s;
}

@media (hover: hover) {
    .option:hover:not(:disabled) {
        background-color: rgba(0, 170, 255, 0.2);
        border-color: var(--accent-color);
    }
}

.option.correct {
    background-color: var(--correct-color);
    border-color: var(--correct-color);
    color: white;
}

.option.incorrect {
    background-color: var(--incorrect-color);
    border-color: var(--incorrect-color);
    color: white;
}

.option:disabled {
    cursor: not-allowed;
}

#feedback-area {
    margin-top: 1.5rem;
    height: 2rem;
}

#feedback {
    font-size: 2rem;
    font-weight: bold;
}

#feedback.correct {
    color: var(--correct-color);
}

#feedback.incorrect {
    color: var(--incorrect-color);
}


#result-screen h1 {
    margin-bottom: 2rem;
}

#score {
    font-size: 2rem;
    font-weight: bold;
    margin-bottom: 1rem;
}

#message {
    font-size: 1.5rem;
    margin-bottom: 2rem;
}

@media (max-width: 600px) {
    body {
        padding: 0.5rem;
    }
    .screen {
        padding: 1rem;
    }
    h1 {
        font-size: 2rem;
    }
    #question {
        font-size: 4rem;
    }
    .option {
        font-size: 1.5rem;
        padding: 1rem;
    }
    .options {
        grid-template-columns: 1fr;
    }
}