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

body {
    background: #000;
    color: #fff;
    font-family: "Segoe UI", sans-serif;
}

header {
    text-align: center;
    padding: 40px 20px;
}

header h1 {
    font-size: 2.5rem;
}

header p {
    margin-top: 10px;
    color: #aaa;
}

main {
    max-width: 600px;
    margin: auto;
    padding: 20px;
}

section {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

#subjects {
}

#subjects h2 {
    text-align: center;
}

button {
    padding: 14px;
    background: #111;
    color: white;
    border: 1px solid #333;
    border-radius: 10px;
    cursor: pointer;
    transition: 0.2s;
}

button:hover {
    background: #222;
}

#quiz {
}

#progress {
    text-align: center;
}

#question {
    text-align: center;
}

#options {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.option {
}

#nextBtn {
    margin-top: 10px;
}

#result {
    text-align: center;
}

#restartBtn {
    margin-top: 15px;
}

.option.selected {
    background: #fff;
    color: #000;
    border-color: #fff;
}