:root {
  --orange: #ea7600;
  --bg: #0a0a0a;
  --card: #141414;
  --border: #2a2a2a;
  --green: #6fd99a;
  --red: #ff7a6b;
}

* { box-sizing: border-box; }

body {
  margin: 0; padding: 2rem 1.2rem;
  background: var(--bg);
  color: #e8e8e8;
  font-family: 'Inter', system-ui, sans-serif;
  line-height: 1.5;
  min-height: 100vh;
}

.container { max-width: 720px; margin: 0 auto; }

header {
  border-bottom: 2px solid var(--orange);
  padding-bottom: 0.8rem; margin-bottom: 1.5rem;
}
header .school { font-size: 0.75rem; color: #888; letter-spacing: 0.15em; text-transform: uppercase; }
header h1 { font-size: 1.6rem; margin: 0.2em 0 0.1em; color: var(--orange); }
header .meta { color: #aaa; font-size: 0.85rem; }

.progress {
  height: 6px; background: #1a1a1a; border-radius: 3px;
  margin: 1rem 0 2rem; overflow: hidden;
}
.progress-bar {
  height: 100%; background: var(--orange);
  width: 0%; transition: width 0.3s ease;
}

.question {
  background: var(--card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--orange);
  border-radius: 6px;
  padding: 1.4rem 1.6rem;
  margin-bottom: 1rem;
}

.question .q-num {
  color: var(--orange); font-weight: 700;
  font-size: 0.78rem; letter-spacing: 0.15em; margin-bottom: 0.4em;
}
.question h2 { margin: 0 0 1em 0; font-size: 1.15rem; color: #fff; line-height: 1.35; }

.options { display: flex; flex-direction: column; gap: 0.5em; }
.option {
  background: #0e0e0e;
  border: 1px solid #2a2a2a;
  border-radius: 5px;
  padding: 0.7em 1em;
  cursor: pointer;
  font-size: 0.95rem;
  text-align: left;
  color: #ddd;
  transition: all 0.15s;
  font-family: inherit;
  width: 100%;
}
.option:hover:not(:disabled) {
  background: #181818; border-color: var(--orange);
}
.option:disabled { cursor: default; }

.option.correct {
  background: rgba(111,217,154,0.12);
  border-color: var(--green);
  color: var(--green);
}
.option.wrong {
  background: rgba(255,122,107,0.12);
  border-color: var(--red);
  color: var(--red);
}
.option .marker { float: right; font-weight: 700; }

.explanation {
  margin-top: 0.8em;
  padding: 0.6em 0.9em;
  background: rgba(234,118,0,0.08);
  border-left: 3px solid var(--orange);
  border-radius: 0 4px 4px 0;
  font-size: 0.85rem;
  color: #ddd;
  display: none;
}
.question.answered .explanation { display: block; }

.actions { margin-top: 1.5rem; text-align: center; }

button.primary {
  background: var(--orange); color: #111;
  border: none; padding: 0.8em 2em;
  border-radius: 5px; font-weight: 700;
  cursor: pointer; font-size: 1rem;
  font-family: inherit;
}
button.primary:hover { filter: brightness(1.1); }
button.primary:disabled { background: #333; color: #666; cursor: default; }

.result {
  text-align: center;
  padding: 2rem;
  background: var(--card);
  border-radius: 8px;
  border: 1px solid var(--border);
  margin-top: 2rem;
  display: none;
}
.result.show { display: block; }
.result h2 { font-size: 2rem; margin: 0 0 0.5em; color: var(--orange); }
.result .score {
  font-size: 3rem; font-weight: 800; color: #fff;
  margin: 0.5em 0;
}
.result .grade { font-size: 1.4rem; color: var(--green); }
.result .grade.medium { color: var(--orange); }
.result .grade.low { color: var(--red); }
.result .actions { margin-top: 1.5em; }

footer {
  margin-top: 3rem; padding-top: 1rem;
  border-top: 1px solid #1a1a1a;
  font-size: 0.78rem; color: #666; text-align: center;
}
footer a { color: var(--orange); text-decoration: none; }