* {
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    margin: 0;
    padding: 28px 16px;

    display: flex;
    justify-content: center;
    align-items: center;

    background:
        radial-gradient(circle at top, #414141, #151515 55%, #050505);

    color: white;
    font-family: "Yu Gothic", "Meiryo", sans-serif;
}

.quiz-device {
    width: min(980px, 100%);
    padding: 22px;

    background:
        linear-gradient(145deg, #e34444, #c42222 38%, #861010 72%, #500707);

    border: 4px solid #450505;
    border-radius: 32px;

    box-shadow:
        0 28px 70px rgba(0, 0, 0, 0.7),
        inset 0 0 0 3px rgba(255, 255, 255, 0.13);
}

.quiz-header {
    display: flex;
    align-items: center;
    gap: 14px;

    margin-bottom: 18px;
    padding: 4px 8px;
}

.quiz-light {
    width: 24px;
    height: 24px;

    background: #60ffb2;
    border: 3px solid #17442d;
    border-radius: 50%;

    box-shadow:
        0 0 10px #60ffb2,
        0 0 24px rgba(96, 255, 178, 0.75);
}

.quiz-header p {
    margin: 0 0 4px;

    color: #ffd9d9;
    font-size: 11px;
    letter-spacing: 0.18em;
}

.quiz-header h1 {
    margin: 0;
    font-size: clamp(24px, 4vw, 36px);
}

.quiz-header a {
    margin-left: auto;
    padding: 10px 17px;

    background: #292929;
    border: 2px solid #666;
    border-radius: 10px;

    color: white;
    font-weight: bold;
    text-decoration: none;
}

.quiz-screen {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;

    padding: 22px;

    background:
        repeating-linear-gradient(
            0deg,
            rgba(255, 255, 255, 0.018) 0,
            rgba(255, 255, 255, 0.018) 2px,
            transparent 2px,
            transparent 5px
        ),
        linear-gradient(#172820, #08110e);

    border: 6px solid #687771;
    border-radius: 19px;

    box-shadow:
        inset 0 0 28px rgba(0, 0, 0, 0.82);
}

.mode-card {
    display: flex;
    flex-direction: column;

    padding: 20px;

    background:
        linear-gradient(
            180deg,
            rgba(31, 52, 43, 0.95),
            rgba(11, 22, 17, 0.98)
        );

    border: 2px solid #577064;
    border-radius: 14px;

    box-shadow:
        inset 0 0 18px rgba(0, 0, 0, 0.45);
}

.mode-card h2 {
    margin: 0 0 12px;

    color: #91ffc8;
    font-size: 21px;
}

.mode-card p {
    flex: 1;

    color: #d7e9df;
    line-height: 1.7;
}

.mode-card form {
    display: flex;
    flex-direction: column;
    gap: 12px;

    margin-top: 14px;
}

.mode-card label {
    font-weight: bold;
}

.mode-card select {
    width: 100%;
    padding: 11px;

    background: #15231d;
    border: 2px solid #5d7469;
    border-radius: 9px;

    color: white;
    font-size: 15px;
}

.mode-card button {
    padding: 13px;

    background:
        linear-gradient(#444, #222);

    border: 2px solid #696969;
    border-radius: 11px;

    color: white;
    font-weight: bold;
    cursor: pointer;

    box-shadow:
        0 5px 0 #111;
}

.mode-card button:hover {
    transform: translateY(2px);

    background:
        linear-gradient(#536c61, #293a33);

    color: #baffdc;

    box-shadow:
        0 3px 0 #111;
}

@media (max-width: 820px) {
    body {
        align-items: flex-start;
    }

    .quiz-screen {
        grid-template-columns: 1fr;
    }
}