/* Original, unbranded classroom UI. No external fonts or libraries. */
:root {
    --page: #111111;
    --card: #ffffff;
    --ink: #111111;
    --muted: #62666e;
    --field: #f2f2f2;
    --line: #e2e2e2;
    --danger: #b42335;
    --focus: #444444;
    font-family: Arial, Helvetica, sans-serif;
    color: var(--ink);
    background: var(--page);
    font-synthesis: none;
    -webkit-text-size-adjust: 100%;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; min-width: 280px; min-height: 100vh; min-height: 100svh; }
button, input, textarea { font: inherit; }
button, a, input { -webkit-tap-highlight-color: transparent; }
button, a { touch-action: manipulation; }
button { cursor: pointer; }
a { color: inherit; }
button:disabled { cursor: not-allowed; }
button:focus-visible, a:focus-visible, input:focus-visible, textarea:focus-visible {
    outline: 3px solid var(--focus);
    outline-offset: 4px;
}
h1:focus { outline: none; }
.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 17px 46px;
    color: #ffffff;
    font-size: 14px;
    line-height: 20px;
}
.course-label { color: #b4b4b4; font-size: 12px; letter-spacing: .08em; }
.environment-label { font-weight: 600; }
.shell { width: min(540px, calc(100% - 32px)); margin: 40px auto 0; padding-bottom: 20px; }
.brand {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 11px;
    width: max-content;
    max-width: 100%;
    margin: 0 auto 42px;
    color: #ffffff;
    font-size: 28px;
    font-weight: 700;
    line-height: 36px;
    letter-spacing: -.9px;
    text-decoration: none;
}
.brand-mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border: 1.5px solid #ffffff;
    border-radius: 9px;
    font-size: 16px;
    letter-spacing: -1px;
}
.card { border-radius: 19px; background: var(--card); padding: 32px 28px 22px; }
.heading-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
h1 { margin: 0; font-size: 22px; font-weight: 600; line-height: 1.3; letter-spacing: -.45px; }
.badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    min-height: 23px;
    padding: 4px 7px;
    border: 1px solid #dddddd;
    border-radius: 5px;
    color: #555555;
    font-size: 10px;
    font-weight: 700;
    line-height: 1;
    letter-spacing: .06em;
}
.subtitle { margin: 10px 0 0; color: var(--muted); font-size: 19px; line-height: 1.4; }
.intro { margin: 30px 0 26px; color: var(--muted); font-size: 15px; line-height: 1.6; }
.recovery-intro { margin: 20px 0 22px; font-size: 14px; }
.label-row { display: flex; justify-content: space-between; gap: 12px; align-items: center; }
.label-row label { font-size: 14px; font-weight: 600; line-height: 20px; }
.word-count { color: var(--muted); font-size: 12px; white-space: nowrap; }
textarea {
    display: block;
    width: 100%;
    height: 116px;
    min-height: 110px;
    margin-top: 9px;
    border: 1px solid transparent;
    border-radius: 17px;
    padding: 16px 18px;
    color: var(--ink);
    background: var(--field);
    font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
    font-size: 16px;
    line-height: 1.7;
    overflow-wrap: anywhere;
    resize: vertical;
}
textarea::placeholder { color: #787878; opacity: 1; }
textarea:focus { border-color: #b7b7b7; }
textarea[aria-invalid="true"] { border-color: var(--danger); }
.field-note { margin: 8px 0 0; color: var(--muted); font-size: 12px; line-height: 1.6; }
.privacy-line { margin: 12px 0 0; color: var(--muted); font-size: 12px; line-height: 1.6; }
.privacy-line strong { color: #333333; }
.status-line { min-height: 18px; margin: 12px 0; font-size: 12px; line-height: 1.5; color: var(--muted); }
.status-line.error { color: var(--danger); }
.form-status { margin: 7px 0 11px; min-height: 0; }
.form-status:empty { display: none; }
.button {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    width: 100%;
    min-height: 55px;
    padding: 12px 20px;
    border: 1px solid transparent;
    border-radius: 999px;
    font-size: 16px;
    font-weight: 600;
    line-height: 22px;
    text-decoration: none;
    transition: background-color .15s ease, border-color .15s ease;
}
.primary-button { background: #171717; color: #ffffff; }
.primary-button:hover:not(:disabled) { background: #333333; }
.primary-button:disabled { background: #777777; color: #e6e6e6; }
#submit-button { margin-top: 17px; }
.divider { margin: 24px 0 16px; color: var(--muted); text-align: center; font-size: 13px; line-height: 20px; }
.secondary-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.secondary-button { background: #ffffff; border-color: var(--line); color: #171717; }
.secondary-button:hover:not(:disabled) { background: #f5f5f5; border-color: #b8b8b8; }
.clear-button { background: #eeeeee; border-color: #555555; }
.text-button { display: block; min-height: 44px; margin: 0 auto; padding: 10px 8px; border: 0; background: transparent; color: #1a1a1a; font-size: 14px; font-weight: 600; line-height: 24px; }
.text-button:hover { text-decoration: underline; }
.back-button { margin-top: 12px; }
.footer { margin-top: 21px; color: #eeeeee; font-size: 12px; text-align: center; line-height: 1.7; }
.footer p { margin: 3px 0; }
.footer-divider { margin: 0 5px; color: #aaaaaa; }
.check-panel {
    display: flex;
    align-items: center;
    gap: 16px;
    min-height: 90px;
    padding: 20px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: #f7f7f7;
    cursor: pointer;
}
.check-panel input { width: 27px; height: 27px; margin: 0; flex-shrink: 0; accent-color: #171717; cursor: pointer; }
.check-copy { display: flex; flex-direction: column; gap: 6px; }
.check-copy strong { font-size: 16px; font-weight: 600; line-height: 1.4; }
.check-copy > span { color: var(--muted); font-size: 12px; line-height: 1.4; }
.check-panel.is-verified { border-color: #777777; }
.check-spinner { width: 20px; height: 20px; margin-left: auto; flex-shrink: 0; border: 2px solid #d0d0d0; border-top-color: #222222; border-radius: 50%; animation: spin .6s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.safety-note { margin-top: 26px; padding-top: 21px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; line-height: 1.7; }
.safety-note strong { color: #222222; }
.success-card { padding-top: 38px; text-align: center; }
.success-symbol { display: grid; place-items: center; width: 62px; height: 62px; margin: 0 auto 24px; border-radius: 50%; background: #f0f0f0; color: #111111; font-size: 31px; }
.success-card h1 { margin-top: 18px; font-size: 25px; }
.message-label { margin: 27px 0 8px; color: var(--muted); font-size: 12px; }
blockquote { margin: 0; font-size: 18px; line-height: 1.6; letter-spacing: -.2px; }
.success-disclaimer { margin: 23px 0 28px; color: var(--muted); font-size: 13px; line-height: 1.7; }
.success-disclaimer strong { color: #333333; }
.redirect-note { margin: 21px 0 2px; color: var(--muted); font-size: 13px; line-height: 1.5; }
.no-script { padding: 16px; border-radius: 12px; background: #ffffff; line-height: 1.6; }
@media (max-width: 600px) {
    .topbar { padding: 16px 20px; }
    .course-label { font-size: 10px; }
    .environment-label { font-size: 12px; }
    .shell { margin-top: 26px; }
    .brand { margin-bottom: 28px; font-size: 26px; }
    .card { padding: 29px 22px 23px; border-radius: 18px; }
    h1 { font-size: 21px; }
    .subtitle { font-size: 18px; }
    .intro { margin-top: 23px; }
    .recovery-intro { margin-bottom: 22px; }
    .secondary-actions { gap: 10px; }
    .button { padding-inline: 12px; font-size: 15px; }
    .footer { padding-inline: 4px; font-size: 11px; }
    .check-panel { padding: 17px; gap: 13px; }
}
@media (max-width: 360px) {
    .topbar { padding-inline: 16px; }
    .course-label { letter-spacing: 0; }
    .card { padding-inline: 19px; }
    h1 { font-size: 19px; }
    .badge { font-size: 9px; padding-inline: 5px; }
    .label-row label { font-size: 13px; }
    textarea { padding-inline: 13px; }
    .button { font-size: 14px; }
    .field-note, .privacy-line { font-size: 11px; }
}
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}