:root {
    --bg: #0b1f33;
    --card: #12324d;
    --line: #2a5573;
    --txt: #eef6fb;
    --muted: #9ec0d6;
    --acc: #3db8e8;
    --ok: #3ecf8e;
    --bom: #7ed957;
    --reg: #f0c14b;
    --ruim: #e05a5a;
}
* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: Segoe UI, Arial, sans-serif;
    background: linear-gradient(160deg, #071422 0%, #0e2a44 50%, #123a4a 100%);
    color: var(--txt);
    min-height: 100vh;
}
.wrap { max-width: 820px; margin: 0 auto; padding: 28px 16px 60px; }
.card {
    background: rgba(18, 50, 77, 0.92);
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 28px;
    box-shadow: 0 12px 40px rgba(0,0,0,.35);
}
h1 { margin: 0 0 8px; font-size: 1.7rem; }
h2 { margin: 0 0 16px; font-size: 1.15rem; color: var(--acc); }
.muted { color: var(--muted); margin: 0 0 20px; }
label { display: block; margin-bottom: 6px; font-weight: 600; }
input[type=text], textarea {
    width: 100%;
    padding: 12px 14px;
    border-radius: 10px;
    border: 1px solid var(--line);
    background: #0b2236;
    color: var(--txt);
    font-size: 1rem;
}
textarea { min-height: 110px; resize: vertical; }
.btn, button.btn {
    display: inline-block;
    background: var(--acc);
    color: #062033;
    font-weight: 700;
    border: 0;
    border-radius: 10px;
    padding: 12px 20px;
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
}
.btn:hover { filter: brightness(1.08); }
.btn.sec { background: transparent; color: var(--txt); border: 1px solid var(--line); margin-left: 8px; }
nav { display: flex; gap: 12px; margin-bottom: 18px; flex-wrap: wrap; }
nav a { color: var(--acc); text-decoration: none; }
.ops { display: grid; gap: 10px; margin: 16px 0 22px; }
.ops label {
    display: flex;
    gap: 10px;
    align-items: flex-start;
    background: #0b2236;
    border: 1px solid var(--line);
    border-radius: 10px;
    padding: 12px;
    font-weight: 500;
    cursor: pointer;
}
.ops label:hover { border-color: var(--acc); }
.bar { height: 8px; background: #0b2236; border-radius: 99px; overflow: hidden; margin: 8px 0 18px; }
.bar > span { display: block; height: 100%; background: var(--acc); }
.tema { font-size: .8rem; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); }
.nota {
    font-size: 3rem;
    font-weight: 800;
    margin: 8px 0;
}
.ok { color: var(--ok); }
.bom { color: var(--bom); }
.reg { color: var(--reg); }
.ruim { color: var(--ruim); }
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--line); }
th { color: var(--muted); font-size: .85rem; }
.erro { color: var(--ruim); margin-bottom: 12px; }
.gab { background: #0b2236; border-radius: 10px; padding: 12px; margin: 10px 0 18px; color: var(--muted); font-size: .95rem; }
.resposta-certa {
    background: #0d3a2a;
    border: 1px solid var(--ok);
    border-radius: 10px;
    padding: 14px 16px;
    margin: 8px 0 20px;
    color: var(--txt);
    font-size: 1.05rem;
    line-height: 1.45;
}
.resposta-certa small { display: block; color: var(--ok); font-weight: 700; margin-bottom: 6px; text-transform: uppercase; letter-spacing: .04em; font-size: .75rem; }
.item-prova { border-bottom: 1px solid var(--line); padding-bottom: 8px; margin-bottom: 16px; }
.row { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
code { background: #0b2236; padding: 2px 6px; border-radius: 6px; }
.btn.nao-sei {
    background: #5a3d2e;
    color: #ffd7c2;
    margin-bottom: 8px;
}