:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --text: #18212f;
  --muted: #667085;
  --border: #d9e1ec;
  --primary: #2257d6;
  --primary-strong: #1742a8;
  --danger: #b42318;
  --danger-bg: #fff1f0;
  --success: #067647;
  --success-bg: #ecfdf3;
  --shadow: 0 18px 45px rgba(16, 24, 40, 0.08);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: radial-gradient(circle at top left, #e7eeff, transparent 34rem), var(--bg);
  color: var(--text);
  min-height: 100vh;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 1rem clamp(1rem, 4vw, 3rem);
  background: rgba(255,255,255,0.86);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand { font-weight: 800; color: var(--text); font-size: 1.2rem; }
.topbar nav { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; }

.page { width: min(1120px, calc(100% - 2rem)); margin: 2rem auto 4rem; }
.footer { color: var(--muted); text-align: center; padding: 2rem 1rem; }

.card {
  background: rgba(255,255,255,0.94);
  border: 1px solid var(--border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: clamp(1rem, 3vw, 2rem);
  margin-bottom: 1.25rem;
}
.narrow { max-width: 480px; margin-left: auto; margin-right: auto; }
.hero { display: grid; grid-template-columns: 1.2fr minmax(260px, 0.8fr); gap: 2rem; align-items: center; }
.stack { display: flex; flex-direction: column; gap: 1rem; }
.grid.two { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: 1.25rem; }

h1, h2, h3 { margin: 0 0 0.5rem; line-height: 1.15; }
h1 { font-size: clamp(2rem, 5vw, 3.25rem); }
h2 { font-size: clamp(1.25rem, 2vw, 1.6rem); }
p { color: var(--muted); line-height: 1.6; }
.eyebrow { color: var(--primary); text-transform: uppercase; letter-spacing: .08em; font-size: .78rem; font-weight: 800; margin: 0 0 .5rem; }
.preline { white-space: pre-line; }
.muted, small, .hint { color: var(--muted); }

label { display: flex; flex-direction: column; gap: .45rem; font-weight: 700; }
input, textarea, select {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: .85rem 1rem;
  font: inherit;
  background: #fff;
  color: var(--text);
}
textarea { resize: vertical; }
input:focus, textarea:focus, select:focus { outline: 3px solid rgba(34, 87, 214, .16); border-color: var(--primary); }

button, .button {
  border: none;
  border-radius: 999px;
  padding: .85rem 1.15rem;
  background: var(--primary);
  color: white;
  font-weight: 800;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .4rem;
  text-decoration: none;
  white-space: nowrap;
}
button:hover, .button:hover { background: var(--primary-strong); text-decoration: none; }
.secondary { background: #eef3ff; color: var(--primary); }
.secondary:hover { background: #e0e9ff; }
.danger { background: var(--danger-bg); color: var(--danger); }
.danger:hover { background: #ffe1df; }
.small { padding: .55rem .8rem; font-size: .9rem; }
.link-button { background: transparent; color: var(--primary); padding: 0; border-radius: 0; }
.link-button:hover { background: transparent; text-decoration: underline; }
.inline-form { display: inline; }
.inline-reset { display: flex; gap: .5rem; align-items: center; flex-wrap: wrap; }
.inline-reset input { width: 180px; padding: .55rem .75rem; border-radius: 10px; }

.code-form { display: flex; flex-direction: column; gap: .8rem; }
.code-form input { font-size: 2rem; text-align: center; letter-spacing: .35em; font-weight: 800; }
.code-pill { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; background: #eef3ff; color: var(--primary); padding: .35rem .55rem; border-radius: .7rem; font-weight: 900; }

.messages { display: grid; gap: .75rem; margin-bottom: 1rem; }
.alert { border-radius: 14px; padding: .9rem 1rem; border: 1px solid var(--border); background: #fff; }
.alert.error { border-color: #fecdca; background: var(--danger-bg); color: var(--danger); }
.alert.success { border-color: #abefc6; background: var(--success-bg); color: var(--success); }

.section-head { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-bottom: 1rem; }
.actions { display: flex; gap: .7rem; align-items: center; }
.wrap { flex-wrap: wrap; }

.names-box { border-top: 1px solid var(--border); padding-top: 1rem; }
.name-row { display: grid; grid-template-columns: 1fr auto; gap: .6rem; margin-bottom: .6rem; }
.choices { display: grid; gap: .75rem; }
.choices label { flex-direction: row; align-items: flex-start; font-weight: 600; background: #f8fafc; border: 1px solid var(--border); padding: .85rem; border-radius: 14px; }
.choices input { width: auto; margin-top: .2rem; }
.uploaded-list { display: grid; gap: .5rem; margin-bottom: .8rem; }
.uploaded-file { flex-direction: row; justify-content: space-between; gap: 1rem; background: #f8fafc; border: 1px solid var(--border); border-radius: 14px; padding: .8rem; font-weight: 600; }
.uploaded-file input { width: auto; }
.task-card h2 { white-space: pre-line; }
.answer-box { background: #f8fafc; border: 1px solid var(--border); border-radius: 14px; padding: 1rem; color: var(--text); }
.submit-bar { display: flex; justify-content: space-between; align-items: center; gap: 1rem; position: sticky; bottom: 1rem; }
.submit-bar p { margin: .25rem 0 0; }
.success-panel input { font-size: .95rem; }

.task-list.compact { display: grid; gap: .65rem; }
.task-preview { display: grid; grid-template-columns: auto 1fr auto; gap: .7rem; align-items: start; background: #f8fafc; border: 1px solid var(--border); border-radius: 14px; padding: .8rem; }
.task-editor-card { background: #f8fafc; border: 1px solid var(--border); border-radius: 18px; padding: 1rem; display: grid; gap: .85rem; }
.hidden { display: none !important; }

.table-card { overflow: hidden; }
.responsive-table { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; min-width: 760px; }
th, td { text-align: left; padding: .9rem; border-bottom: 1px solid var(--border); vertical-align: top; }
th { color: var(--muted); font-size: .85rem; text-transform: uppercase; letter-spacing: .06em; }
.actions-cell { display: flex; gap: .45rem; flex-wrap: wrap; min-width: 260px; }
.badge { display: inline-block; padding: .35rem .55rem; border-radius: 999px; font-weight: 800; font-size: .85rem; }
.badge.ok { background: var(--success-bg); color: var(--success); }
.badge.muted { background: #f2f4f7; color: var(--muted); }

@media (max-width: 760px) {
  .hero, .grid.two { grid-template-columns: 1fr; }
  .topbar { align-items: flex-start; }
  .section-head, .submit-bar { align-items: stretch; flex-direction: column; }
  .name-row { grid-template-columns: 1fr; }
  .task-preview { grid-template-columns: auto 1fr; }
  .task-preview small { grid-column: 1 / -1; }
  button, .button { width: 100%; }
  .inline-form, .inline-form button, .actions-cell .button { width: 100%; }
}

.material-box { border-top: 1px solid var(--border); padding-top: 1rem; }
.material-list, .material-downloads { display: grid; gap: .6rem; }
.material-file, .material-download {
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: .85rem;
  font-weight: 600;
}
.material-file input { width: auto; }
.material-download { color: var(--text); text-decoration: none; }
.material-download:hover { background: #eef3ff; text-decoration: none; }
.material-download small { white-space: nowrap; }
.task-description { margin-top: -.25rem; margin-bottom: 1rem; }
.task-preview-main { display: grid; gap: .25rem; }
.task-preview-title { font-weight: 800; color: var(--text); }
.task-preview-description { color: var(--muted); white-space: pre-line; }