:root {
  --bg: #0f1420;
  --panel: #1a2233;
  --panel-2: #222c41;
  --text: #e7ecf5;
  --muted: #9aa7bd;
  --accent: #4f8cff;
  --good: #2ecc71;
  --bad: #ff5c6c;
  --border: #2c3650;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
}
a { color: var(--accent); text-decoration: none; }

/* DotField animated background */
#dotfield-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}
#dotfield-bg canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
header, .container { position: relative; z-index: 1; }

header {
  display: flex; align-items: center; gap: 16px;
  padding: 14px 22px; border-bottom: 1px solid var(--border);
}
header .logo { font-weight: 700; letter-spacing: .3px; }
header nav { display: flex; gap: 16px; margin-left: auto; }
.container { max-width: 1000px; margin: 0 auto; padding: 28px 22px; }

.home { min-height: 70vh; display: flex; align-items: center; justify-content: center; }
.home .buttons { display: flex; gap: 28px; flex-wrap: wrap; justify-content: center; }
.bigbtn {
  width: 280px; height: 200px; border-radius: 18px;
  background: var(--panel); border: 1px solid var(--border);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 12px; cursor: pointer; transition: transform .12s, border-color .12s;
}
.bigbtn:hover { transform: translateY(-3px); border-color: var(--accent); }
.bigbtn .icon { font-size: 52px; }
.bigbtn .label { font-size: 22px; font-weight: 600; }
.bigbtn .sub { color: var(--muted); font-size: 13px; }

button, .btn {
  background: var(--accent); color: #fff; border: 0; border-radius: 10px;
  padding: 10px 16px; font-size: 14px; cursor: pointer;
}
button.ghost { background: var(--panel-2); }
button:disabled { opacity: .5; cursor: default; }

.card { background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 18px; margin-bottom: 16px; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
input, select {
  background: var(--panel-2); color: var(--text);
  border: 1px solid var(--border); border-radius: 8px; padding: 9px 11px; font-size: 14px;
}
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--border); font-size: 14px; }
.badge { font-size: 12px; padding: 2px 8px; border-radius: 999px; background: var(--panel-2); color: var(--muted); }
.badge.ready { color: var(--good); }
.badge.processing { color: #f5c451; }
.muted { color: var(--muted); }

.answer-bar {
  position: sticky; top: 0; z-index: 5;
  font-size: 20px; font-weight: 700; text-align: center;
  padding: 16px; border-radius: 12px; margin-bottom: 20px;
  background: var(--panel-2); border: 1px solid var(--border);
}
.answer-bar.good { background: rgba(46,204,113,.15); border-color: var(--good); color: var(--good); }
.answer-bar.bad { background: rgba(255,92,108,.15); border-color: var(--bad); color: var(--bad); }
.option {
  display: block; width: 100%; text-align: left; margin: 8px 0;
  background: var(--panel-2); border: 1px solid var(--border); color: var(--text);
  padding: 14px; border-radius: 10px; font-size: 15px;
}
.option:hover { border-color: var(--accent); }
.option.correct { border-color: var(--good); background: rgba(46,204,113,.12); }
.option.wrong { border-color: var(--bad); background: rgba(255,92,108,.12); }
.explanation { margin-top: 14px; padding: 14px; border-left: 3px solid var(--accent); background: var(--panel-2); border-radius: 8px; }

.note { display: inline-block; background: var(--panel-2); border: 1px solid var(--border);
  border-radius: 10px; padding: 10px 12px; margin: 6px; max-width: 320px; vertical-align: top; }
.note h4 { margin: 0 0 6px; font-size: 14px; }
.note p { margin: 0; font-size: 12px; color: var(--muted); }
.note .links { margin-top: 6px; font-size: 11px; }