:root {
  color-scheme: light;
  --bg: #f5f7f4;
  --surface: #ffffff;
  --surface-muted: #eef2ec;
  --text: #18201b;
  --muted: #5b665f;
  --line: #d8dfd5;
  --accent: #19764b;
  --accent-dark: #105c39;
  --danger: #a93a2f;
  --warn: #b45f1a;
  --warn-bg: #fff6eb;
  --weak: #a93a2f;
  --weak-bg: #fdf2f1;
  --good: #1a6b8f;
  --good-bg: #eef7fb;
  --strong: #19764b;
  --strong-bg: #f0faf3;
  --neutral: #6b7570;
  --neutral-bg: #f4f5f4;
  --radius: 8px;
  --shadow-sm: 0 1px 3px rgba(24,32,27,.06);
  --shadow-md: 0 4px 16px rgba(24,32,27,.08);
}

*, *::before, *::after { box-sizing:border-box; }

body {
  margin:0; min-height:100vh;
  background:var(--bg); color:var(--text);
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  -webkit-font-smoothing:antialiased;
}

button,input,textarea,select { font:inherit; }

/* ===== LOGIN ===== */
.login-page {
  display:flex; align-items:center; justify-content:center;
  min-height:100vh; padding:24px;
  background:linear-gradient(160deg,#f5f7f4 0%,#e3ebe0 100%);
}
.login-card {
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:16px; padding:48px 40px 36px;
  max-width:400px; width:100%; text-align:center;
  box-shadow:0 16px 48px rgba(24,32,27,.08);
}
.login-brand {
  color:var(--accent); font-size:13px; font-weight:750;
  letter-spacing:.08em; margin-bottom:16px;
}
.login-heading {
  margin:0; font-size:clamp(28px,6vw,40px);
  line-height:1.12; letter-spacing:-.01em;
}
.login-desc {
  margin:12px auto 32px; max-width:30ch;
  color:var(--muted); font-size:15px; line-height:1.55;
}
.login-lang { margin-top:28px; justify-content:center; }
.login-error {
  margin-top:16px; padding:10px 14px; border-radius:var(--radius);
  background:var(--weak-bg); color:var(--weak);
  font-size:13px; display:none;
}
.login-error.visible { display:block; }

/* ===== TOPBAR ===== */
.topbar {
  display:flex; align-items:center; justify-content:space-between;
  height:52px; padding:0 20px;
  background:var(--surface); border-bottom:1px solid var(--line);
  position:sticky; top:0; z-index:10;
}
.topbar-brand {
  color:var(--accent); font-size:12px; font-weight:750;
  letter-spacing:.06em; white-space:nowrap;
}
.topbar-center { display:flex; align-items:center; }
.topbar-right {
  display:flex; align-items:center; gap:12px;
}
.step-indicator {
  font-size:12px; font-weight:650; color:var(--muted);
}
.user-menu { display:flex; align-items:center; gap:8px; }
.user-name {
  font-size:12px; font-weight:650; color:var(--muted);
  max-width:140px; overflow:hidden; text-overflow:ellipsis; white-space:nowrap;
}
.icon-btn {
  min-height:32px; width:32px; border:0; border-radius:6px;
  background:transparent; color:var(--muted);
  cursor:pointer; font-size:16px; display:inline-flex;
  align-items:center; justify-content:center;
}
.icon-btn:hover { background:var(--surface-muted); color:var(--text); }
.link-btn {
  border:0; background:none; color:var(--muted);
  cursor:pointer; font-size:12px; padding:4px 8px; border-radius:4px;
}
.link-btn:hover { background:var(--surface-muted); color:var(--text); }
.link-btn:disabled { opacity:.4; cursor:not-allowed; }

/* ===== LANG SWITCH ===== */
.lang-switch {
  display:inline-flex; gap:3px;
  background:var(--surface-muted); border-radius:6px; padding:2px;
}
.lang-btn {
  min-height:26px; padding:0 8px; border:0; border-radius:4px;
  background:transparent; color:var(--muted);
  font-size:11px; font-weight:750; cursor:pointer;
}
.lang-btn:hover { background:rgba(24,32,27,.04); color:var(--text); }
.lang-btn.is-active {
  background:var(--surface); color:var(--accent);
  box-shadow:0 1px 2px rgba(24,32,27,.06);
}

/* ===== MAIN GRID ===== */
.main-grid {
  display:grid;
  grid-template-columns:1fr 340px;
  min-height:calc(100vh - 52px);
}
.main-pane {
  padding:28px 32px; display:flex; flex-direction:column; gap:20px;
  max-width:800px;
}
.feedback-sidebar {
  background:var(--surface);
  border-left:1px solid var(--line);
  padding:24px 20px;
  overflow-y:auto;
}

/* ===== SETUP CARD ===== */
.setup-card {
  background:var(--surface); border:1px solid var(--line);
  border-radius:var(--radius); padding:24px;
  box-shadow:var(--shadow-sm);
}
.card-header { margin-bottom:18px; }
.card-header h2 { margin:0 0 4px; font-size:20px; }
.card-hint { margin:0; color:var(--muted); font-size:13px; line-height:1.5; }

.inline-form { display:flex; gap:12px; align-items:end; flex-wrap:wrap; }
.field-row { display:flex; gap:12px; flex:1; min-width:0; }
.field-row label { flex:1; min-width:0; }

.stacked-form { display:grid; gap:14px; }

label { display:grid; gap:6px; color:var(--muted); font-size:12px; font-weight:650; }

input, textarea, select {
  width:100%; border:1px solid var(--line); border-radius:var(--radius);
  background:#fbfcfa; color:var(--text); padding:10px 12px; outline:none;
}
select {
  appearance:none;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%235b665f' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat:no-repeat; background-position:right 10px center;
  padding-right:32px;
}
textarea { min-height:120px; resize:vertical; line-height:1.5; }
input:focus, textarea:focus, select:focus {
  border-color:var(--accent); box-shadow:0 0 0 3px rgba(25,118,75,.1);
}

/* ===== BUTTONS ===== */
button {
  min-height:40px; border:0; border-radius:var(--radius);
  background:var(--accent); color:#fff; cursor:pointer;
  font-weight:650; display:inline-flex; align-items:center;
  justify-content:center; gap:8px; padding:0 20px;
  transition:background .15s ease,transform .1s ease;
  white-space:nowrap;
}
button:hover:not(:disabled) { background:var(--accent-dark); }
button:active:not(:disabled) { transform:translateY(1px); }
button:disabled { cursor:not-allowed; opacity:.45; }
.btn-spinner {
  display:none; width:14px; height:14px;
  border:2px solid rgba(255,255,255,.3); border-top-color:#fff;
  border-radius:50%; animation:spin .8s linear infinite;
}
button.is-loading .btn-text { opacity:.85; }
button.is-loading .btn-spinner { display:inline-block; }
@keyframes spin { to { transform:rotate(360deg); } }

/* ===== STATUS / ERROR ===== */
.status-line {
  display:flex; align-items:center; gap:8px;
  min-height:18px; margin:14px 0 0; font-size:12px; color:var(--muted);
}
.status-dot {
  display:inline-block; width:7px; height:7px; border-radius:50%; background:var(--accent);
}
.status-line.is-busy .status-dot { background:var(--warn); animation:pulse 1.2s ease-in-out infinite; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:.3} }
.error-line {
  min-height:18px; margin:8px 0 0; font-size:12px; color:var(--danger);
}

/* ===== QUESTION BAR ===== */
.question-bar { margin-top:4px; }
.bar-label { font-size:12px; font-weight:650; color:var(--muted); margin-bottom:10px; }
.question-tabs {
  display:flex; flex-wrap:wrap; gap:8px;
}
.question-tab {
  border:1px solid var(--line); border-radius:var(--radius);
  background:#fbfcfa; color:var(--text); padding:10px 16px;
  cursor:pointer; font-size:13px; font-weight:500; text-align:left;
  transition:border-color .15s,border-left-color .15s,background .15s;
  border-left:3px solid transparent;
}
.question-tab:hover { border-color:var(--accent); }
.question-tab[aria-selected="true"] {
  border-color:var(--accent); border-left-color:var(--accent);
  background:var(--surface-muted); font-weight:650;
}
.question-tab-id {
  display:block; font-size:11px; color:var(--accent); font-weight:750; margin-bottom:3px;
}

/* ===== ANSWER AREA ===== */
.answer-form { display:grid; gap:12px; }
.answer-header {
  display:flex; align-items:baseline; justify-content:space-between; gap:12px;
}
.answer-header label {
  font-size:14px; font-weight:700; color:var(--text);
}
.answer-hint { font-size:12px; color:var(--muted); }

/* ===== TOOLS PANEL ===== */
.tools-divider {
  height:1px; background:var(--line); margin:12px 0 8px;
}
.tools-panel { display:flex; flex-direction:column; gap:16px; }
.tools-panel h2 { font-size:18px; margin:0; }

/* ===== FEEDBACK SIDEBAR ===== */
.sidebar-empty {
  text-align:center; padding:40px 12px; color:var(--muted);
}
.sidebar-empty .empty-icon {
  width:40px; height:40px; margin:0 auto 14px; opacity:.35;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='40' height='40' viewBox='0 0 24 24' fill='none' stroke='%235b665f' stroke-width='1.5' stroke-linecap='round'%3E%3Cpath d='M12 20h9'/%3E%3Cpath d='M16.5 3.5a2.121 2.121 0 0 1 3 3L7 19l-4 1 1-4Z'/%3E%3C/svg%3E");
  background-size:contain; background-repeat:no-repeat; background-position:center;
}
.sidebar-empty p { margin:0; font-size:13px; line-height:1.55; }
.feedback-content { display:flex; flex-direction:column; gap:16px; }

/* Grade badge */
.feedback-grade { text-align:center; padding:8px 0 4px; }
.grade-badge {
  display:inline-block; padding:6px 20px; border-radius:999px;
  font-size:14px; font-weight:800; letter-spacing:.02em;
}
.grade-badge.miss   { background:var(--weak-bg); color:var(--weak); }
.grade-badge.partial{ background:var(--warn-bg); color:var(--warn); }
.grade-badge.solid  { background:var(--good-bg); color:var(--good); }
.grade-badge.strong { background:var(--strong-bg); color:var(--strong); }
.grade-summary {
  margin:8px 0 0; font-size:12px; color:var(--muted);
}

/* Score metrics */
.score-metrics { display:grid; gap:1px; background:var(--line); border-radius:var(--radius); overflow:hidden; }
.metric-row {
  display:grid; grid-template-columns:1fr auto;
  gap:8px; padding:10px 14px; background:var(--surface);
  font-size:13px;
}
.metric-row strong { color:var(--accent); }

/* Feedback blocks */
.feedback-block { display:none; }
.feedback-block.has-content { display:block; }
.feedback-block h4 {
  margin:0 0 6px; font-size:12px; font-weight:750; color:var(--muted);
  letter-spacing:.03em; text-transform:uppercase;
}
.feedback-block ul {
  margin:0; padding-left:18px; font-size:13px; color:var(--muted); line-height:1.6;
}

/* ===== PROGRESS SECTION ===== */
.sidebar-divider {
  height:1px; background:var(--line); margin:20px 0;
}
.progress-content { display:flex; flex-direction:column; gap:14px; }
.progress-header {
  display:flex; align-items:center; justify-content:space-between;
}
.progress-header h3 { margin:0; font-size:16px; }
.progress-bar-wrap {
  position:relative; height:28px; background:var(--surface-muted);
  border-radius:14px; overflow:hidden;
}
.progress-bar {
  height:100%; background:var(--accent); border-radius:14px;
  transition:width .5s ease;
  min-width:0;
}
.progress-bar.high { background:var(--strong); }
.progress-bar.medium { background:var(--good); }
.progress-bar.low { background:var(--warn); }
.progress-pct {
  position:absolute; right:14px; top:50%; transform:translateY(-50%);
  font-size:12px; font-weight:800; color:var(--text);
}

/* Concept pills */
.concept-list { display:flex; flex-wrap:wrap; gap:6px; }
.concept-pill {
  display:inline-flex; align-items:center; gap:6px;
  border:1px solid var(--line); border-radius:999px;
  padding:5px 12px; font-size:12px; font-weight:650; background:var(--surface);
}
.pill-neutral { background:var(--neutral-bg); border-color:#d5dad3; color:var(--neutral); }
.pill-weak    { background:var(--weak-bg);   border-color:#e8bdb9; color:var(--weak); }
.pill-warn    { background:var(--warn-bg);   border-color:#edd5b5; color:var(--warn); }
.pill-good    { background:var(--good-bg);   border-color:#b8d9e8; color:var(--good); }
.pill-strong  { background:var(--strong-bg); border-color:#b8dfc6; color:var(--strong); }

/* Challenge */
.challenge-block {
  border:1px solid var(--line); border-radius:var(--radius);
  padding:14px; font-size:13px; line-height:1.55; color:var(--muted);
}
.challenge-block strong { color:var(--text); }

/* ===== EMPTY STATE ===== */
.empty-state {
  border:1px dashed var(--line); border-radius:var(--radius);
  color:var(--muted); padding:18px 16px; text-align:center;
  font-size:12px; line-height:1.5;
}
.empty-hint::before {
  content:""; display:block; width:20px; height:20px;
  margin:0 auto 8px; opacity:.4;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%235b665f' stroke-width='1.5' stroke-linecap='round'%3E%3Ccircle cx='12' cy='12' r='10'/%3E%3Cpath d='M12 16v-4'/%3E%3Cpath d='M12 8h.01'/%3E%3C/svg%3E");
  background-size:contain;
}

/* ===== ONTOLOGY ===== */
.ontology-view { display:grid; gap:10px; }
.summary-strip { display:flex; flex-wrap:wrap; gap:8px; }
.summary-chip {
  background:var(--surface-muted); border-radius:999px;
  color:var(--muted); font-size:11px; font-weight:750; padding:5px 10px;
}
.prompt-text {
  background:#fbfcfa; border:1px solid var(--line); border-radius:var(--radius);
  margin:0; padding:12px; white-space:pre-wrap; font-size:12px; line-height:1.5; color:var(--text);
}

/* ===== FILE UPLOAD ===== */
.file-upload-row {
  display: flex;
  align-items: center;
  gap: 10px;
  grid-column: 1 / -1;
}

.file-label {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 13px;
  font-weight: 650;
  color: var(--muted);
}

.file-label input[type="file"] {
  padding: 8px;
  font-size: 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fbfcfa;
  color: var(--text);
  cursor: pointer;
  min-width: 200px;
}

.file-label input[type="file"]::file-selector-button {
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: 6px 10px;
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  font-size: 12px;
  font-weight: 650;
  margin-right: 10px;
}

.file-label input[type="file"]::file-selector-button:hover {
  background: var(--surface-muted);
}

.file-name {
  font-size: 12px;
  color: var(--muted);
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.paste-toggle {
  grid-column: 1 / -1;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 10px 14px;
  background: #fbfcfa;
}

.paste-toggle summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 12px;
  font-weight: 650;
}

.paste-toggle[open] summary {
  margin-bottom: 12px;
}

.paste-toggle .wide-field {
  grid-column: 1 / -1;
}

.small-button {
  min-height: 32px;
  padding: 0 14px;
  font-size: 12px;
}

/* ===== RESPONSIVE ===== */
@media (max-width:900px) {
  .main-grid { grid-template-columns:1fr; }
  .main-pane { padding:20px; }
  .feedback-sidebar { border-left:0; border-top:1px solid var(--line); padding:20px; }
  .topbar { flex-wrap:wrap; height:auto; gap:8px; padding:10px 14px; }
  .topbar-right { flex-wrap:wrap; justify-content:flex-end; }
}