/* ── Variables ───────────────────────────────────────────────────── */
:root {
  --bg: #080a0e;
  --bg2: #0d1017;
  --panel: #0f1318;
  --border: #1e2530;
  --border2: #2a3340;
  --amber: #f5a623;
  --amber2: #ffc947;
  --amber-dim: rgba(245,166,35,0.12);
  --amber-glow: rgba(245,166,35,0.25);
  --green: #39e07a;
  --red: #f55353;
  --blue: #4d9fff;
  --text: #d8dde8;
  --text-muted: #5a6477;
  --text-dim: #2e3848;
  --font-display: 'Bebas Neue', sans-serif;
  --font-serif: 'Instrument Serif', serif;
  --font-mono: 'DM Mono', monospace;
  --radius: 2px;
  --transition: 0.2s ease;
}

/* ── Reset ───────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-mono);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
  cursor: crosshair;
}

/* ── Grid Canvas Background ──────────────────────────────────────── */
#gridCanvas {
  position: fixed; inset: 0; z-index: 0;
  pointer-events: none; opacity: 0.4;
}

/* Scanline effect */
.scanline {
  position: fixed; inset: 0; z-index: 1; pointer-events: none;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0,0,0,0.03) 2px,
    rgba(0,0,0,0.03) 4px
  );
}

/* ── Header ──────────────────────────────────────────────────────── */
header {
  position: relative; z-index: 10;
  border-bottom: 1px solid var(--border);
  background: rgba(8,10,14,0.95);
  backdrop-filter: blur(12px);
}

.header-inner {
  max-width: 900px; margin: 0 auto;
  padding: 1.2rem 2rem;
  display: flex; align-items: center; justify-content: space-between;
}

.logo { display: flex; align-items: center; gap: 1rem; }

.logo-icon {
  color: var(--amber);
  animation: hexSpin 12s linear infinite;
  display: flex;
}

@keyframes hexSpin {
  0%, 100% { transform: rotate(0deg); }
  50% { transform: rotate(180deg); }
}

.logo-text-group { display: flex; flex-direction: column; gap: 0.1rem; }

.logo-name {
  font-family: var(--font-display);
  font-size: 1.8rem; letter-spacing: 0.05em;
  color: var(--text); line-height: 1;
}

.logo-name em {
  font-style: normal; color: var(--amber);
}

.logo-sub {
  font-size: 0.6rem; letter-spacing: 0.2em;
  color: var(--text-muted); line-height: 1;
}

.header-status {
  display: flex; align-items: center; gap: 0.5rem;
  font-size: 0.65rem; letter-spacing: 0.2em; color: var(--green);
}

.status-dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 8px var(--green);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 8px var(--green); }
  50% { opacity: 0.5; box-shadow: 0 0 3px var(--green); }
}

/* ── Mission Strip ───────────────────────────────────────────────── */
.mission-strip {
  position: relative; z-index: 10;
  background: var(--amber-dim);
  border-bottom: 1px solid rgba(245,166,35,0.2);
  padding: 0.5rem 2rem;
  display: flex; align-items: center; justify-content: center; gap: 1.5rem;
  font-size: 0.65rem; letter-spacing: 0.25em; color: var(--amber);
  overflow: hidden;
}

.mission-strip .arrow { color: var(--amber); opacity: 0.4; }

/* ── Main ────────────────────────────────────────────────────────── */
main {
  position: relative; z-index: 5;
  max-width: 900px; margin: 0 auto;
  padding: 3rem 2rem 6rem;
  display: flex; flex-direction: column; gap: 3rem;
}

/* ── Steps ───────────────────────────────────────────────────────── */
.step { display: flex; flex-direction: column; gap: 1.5rem; }
.step.hidden { display: none; }

.step-header { display: flex; align-items: flex-start; gap: 1.5rem; }

.step-num {
  font-family: var(--font-display);
  font-size: 5rem; line-height: 1;
  color: var(--border2); letter-spacing: -0.02em;
  flex-shrink: 0; margin-top: -0.5rem;
  transition: color 0.3s;
}

.step:not(.hidden) .step-num { color: var(--amber); }

.step-title {
  font-family: var(--font-display);
  font-size: 2rem; letter-spacing: 0.08em;
  color: var(--text); line-height: 1;
}

.step-desc {
  font-size: 0.75rem; color: var(--text-muted);
  letter-spacing: 0.05em; margin-top: 0.3rem;
  font-style: italic; font-family: var(--font-serif);
}

/* ── Panel ───────────────────────────────────────────────────────── */
.panel {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--border);
  padding: 2rem;
  display: flex; flex-direction: column; gap: 1.5rem;
}

/* Corner decorations */
.panel-corner {
  position: absolute; width: 12px; height: 12px;
  border-color: var(--amber); border-style: solid;
}
.panel-corner.tl { top: -1px; left: -1px; border-width: 2px 0 0 2px; }
.panel-corner.tr { top: -1px; right: -1px; border-width: 2px 2px 0 0; }
.panel-corner.bl { bottom: -1px; left: -1px; border-width: 0 0 2px 2px; }
.panel-corner.br { bottom: -1px; right: -1px; border-width: 0 2px 2px 0; }

/* ── Drop Zone ───────────────────────────────────────────────────── */
.drop-zone {
  border: 1px dashed var(--border2);
  padding: 3rem 2rem;
  display: flex; justify-content: center; align-items: center;
  transition: border-color var(--transition), background var(--transition);
  cursor: pointer;
  position: relative; overflow: hidden;
}

.drop-zone::before {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(ellipse at center, var(--amber-dim) 0%, transparent 70%);
  opacity: 0; transition: opacity 0.3s;
}

.drop-zone:hover::before, .drop-zone.dragover::before { opacity: 1; }
.drop-zone:hover, .drop-zone.dragover { border-color: var(--amber); }

.dz-inner {
  display: flex; flex-direction: column; align-items: center; gap: 1rem;
  position: relative; z-index: 1;
}

.dz-icon { color: var(--text-muted); transition: color 0.3s; }
.drop-zone:hover .dz-icon { color: var(--amber); }

.dz-title {
  font-family: var(--font-display);
  font-size: 1.2rem; letter-spacing: 0.15em; color: var(--text);
}

.dz-meta {
  font-size: 0.65rem; letter-spacing: 0.2em;
  color: var(--text-muted);
}

.answer-file-row {
  display: flex; align-items: center; gap: 1rem;
  background: var(--bg2); border: 1px solid var(--border);
  padding: 0.9rem 1.2rem; flex-wrap: wrap;
}

.answer-file-row .mini-icon { color: var(--amber); font-size: 1.2rem; }
#answerFileName { flex: 1; font-size: 0.75rem; color: var(--text-muted); letter-spacing: 0.05em; }

/* ── File Info ───────────────────────────────────────────────────── */
.file-info {
  background: rgba(57,224,122,0.06);
  border: 1px solid rgba(57,224,122,0.2);
  padding: 0.75rem 1rem;
  display: flex; align-items: center; gap: 0.75rem;
  font-size: 0.75rem; letter-spacing: 0.05em;
}

.fi-icon { color: var(--green); }
.fi-name { color: var(--green); flex: 1; }
.fi-size { color: var(--text-muted); }

/* ── Buttons ─────────────────────────────────────────────────────── */
.btn-primary {
  background: var(--amber);
  color: var(--bg);
  border: none; padding: 1rem 2rem;
  font-family: var(--font-display);
  font-size: 1rem; letter-spacing: 0.15em;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center; gap: 1rem;
  transition: all var(--transition);
  position: relative; overflow: hidden;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
}

.btn-primary::before {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.15) 0%, transparent 50%);
}

.btn-primary:hover:not(:disabled) {
  background: var(--amber2);
  box-shadow: 0 0 30px var(--amber-glow);
  transform: translateY(-1px);
}

.btn-primary:disabled { opacity: 0.3; cursor: not-allowed; }

.btn-outline {
  background: transparent; color: var(--amber);
  border: 1px solid var(--amber);
  padding: 0.6rem 1.4rem;
  font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.15em;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-outline:hover {
  background: var(--amber-dim);
  box-shadow: 0 0 15px var(--amber-glow);
}

.btn-outline.sm { padding: 0.35rem 0.8rem; font-size: 0.65rem; }

.btn-restart {
  background: transparent; color: var(--text-muted);
  border: 1px solid var(--border2);
  padding: 0.9rem 2rem; width: 100%;
  font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.2em;
  cursor: pointer; transition: all var(--transition);
}

.btn-restart:hover { color: var(--amber); border-color: var(--amber); }

/* Loader */
.btn-loader {
  width: 16px; height: 16px;
  border: 2px solid rgba(8,10,14,0.3);
  border-top-color: var(--bg);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* ── Exam Header ─────────────────────────────────────────────────── */
.exam-header { display: flex; flex-direction: column; gap: 1rem; }
.exam-title-row { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; }

#examTitle {
  font-family: var(--font-serif);
  font-size: 1.6rem; color: var(--text);
  font-style: italic;
}

.subject-badge {
  background: var(--amber-dim);
  border: 1px solid rgba(245,166,35,0.3);
  color: var(--amber);
  padding: 0.2rem 0.75rem;
  font-size: 0.65rem; letter-spacing: 0.2em;
}

.exam-tags { display: flex; gap: 0.75rem; }

.etag {
  display: flex; flex-direction: column; align-items: center;
  background: var(--bg2); border: 1px solid var(--border);
  padding: 0.5rem 1rem; min-width: 60px;
}

.etag-num {
  font-family: var(--font-display); font-size: 1.4rem;
  color: var(--amber); line-height: 1;
}

.etag-label {
  font-size: 0.55rem; letter-spacing: 0.2em;
  color: var(--text-muted); margin-top: 0.15rem;
}

.exam-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border2), transparent);
}

/* ── Exam Questions ──────────────────────────────────────────────── */
.exam-section { margin-bottom: 1.5rem; }

.exam-section-title {
  font-family: var(--font-display);
  font-size: 0.85rem; letter-spacing: 0.2em; color: var(--amber);
  margin-bottom: 1rem;
  display: flex; align-items: center; gap: 0.75rem;
}

.exam-section-title::after {
  content: ''; flex: 1; height: 1px; background: var(--border);
}

.q-block {
  border: 1px solid var(--border);
  padding: 1.2rem 1.4rem; margin-bottom: 0.75rem;
  position: relative;
  transition: border-color var(--transition);
}

.q-block:hover { border-color: var(--border2); }

.q-block::before {
  content: '';
  position: absolute; left: 0; top: 0; bottom: 0;
  width: 2px; background: var(--amber); opacity: 0;
  transition: opacity var(--transition);
}

.q-block:hover::before { opacity: 1; }

.q-num {
  font-size: 0.65rem; letter-spacing: 0.15em;
  color: var(--amber); margin-bottom: 0.5rem;
}

.q-text { font-size: 0.88rem; line-height: 1.6; color: var(--text); }

.options-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0.4rem; margin-top: 0.75rem; }

.option {
  display: flex; gap: 0.6rem; align-items: flex-start;
  background: var(--bg2); padding: 0.5rem 0.75rem;
  font-size: 0.8rem; border: 1px solid transparent;
  transition: border-color var(--transition);
}

.option:hover { border-color: var(--border); }
.opt-key { color: var(--amber); font-weight: 500; flex-shrink: 0; }

.keywords { display: flex; flex-wrap: wrap; gap: 0.35rem; margin-top: 0.75rem; }
.kw {
  background: rgba(77,159,255,0.08);
  border: 1px solid rgba(77,159,255,0.2);
  color: var(--blue); padding: 0.15rem 0.6rem;
  font-size: 0.65rem; letter-spacing: 0.1em;
}

.io-tags { display: flex; gap: 0.5rem; margin-top: 0.6rem; flex-wrap: wrap; }
.io-tag {
  background: var(--bg2); border: 1px solid var(--border);
  padding: 0.2rem 0.6rem; font-size: 0.65rem;
  color: var(--text-muted); letter-spacing: 0.1em;
}

/* ── Answer Section ──────────────────────────────────────────────── */
.answer-section { display: flex; flex-direction: column; gap: 1rem; }

.answer-label {
  font-size: 0.7rem; letter-spacing: 0.2em; color: var(--amber);
  display: flex; align-items: center; gap: 0.5rem;
}

/* ── Score Dashboard ─────────────────────────────────────────────── */
.score-dashboard {
  display: flex; gap: 3rem; align-items: center; flex-wrap: wrap;
}

.score-main { display: flex; flex-direction: column; align-items: center; gap: 0.5rem; }

.score-ring-wrap { position: relative; width: 140px; height: 140px; }

.ring-svg { transform: rotate(-90deg); width: 100%; height: 100%; }

.ring-track {
  fill: none; stroke: var(--border2); stroke-width: 8;
}

.ring-progress {
  fill: none; stroke: var(--amber); stroke-width: 8;
  stroke-linecap: butt;
  stroke-dasharray: 364; stroke-dashoffset: 364;
  transition: stroke-dashoffset 1.4s cubic-bezier(0.4,0,0.2,1),
              stroke 0.5s ease;
  filter: drop-shadow(0 0 6px var(--amber));
}

.score-center {
  position: absolute; inset: 0;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
}

.score-pct {
  font-family: var(--font-display); font-size: 2.2rem;
  color: var(--amber); letter-spacing: 0.02em; line-height: 1;
}

.score-grade {
  font-size: 0.65rem; letter-spacing: 0.2em;
  color: var(--text-muted); margin-top: 0.2rem;
}

.score-label {
  font-size: 0.6rem; letter-spacing: 0.25em; color: var(--text-muted);
}

.score-stats { flex: 1; display: flex; flex-direction: column; gap: 1.2rem; min-width: 200px; }

.stat-bar-wrap { display: flex; flex-direction: column; gap: 0.4rem; }

.stat-name { font-size: 0.6rem; letter-spacing: 0.2em; color: var(--text-muted); }

.stat-bar {
  height: 4px; background: var(--border2);
  position: relative; overflow: visible;
}

.stat-fill {
  height: 100%; background: var(--amber);
  width: 0%; transition: width 1.2s cubic-bezier(0.4,0,0.2,1);
  position: relative;
  box-shadow: 0 0 8px var(--amber-glow);
}

.stat-fill::after {
  content: ''; position: absolute;
  right: -1px; top: -2px;
  width: 3px; height: 8px;
  background: var(--amber2);
}

.stat-val {
  font-family: var(--font-display); font-size: 1rem;
  color: var(--text); letter-spacing: 0.05em;
}

/* ── Result Blocks ───────────────────────────────────────────────── */
.result-block { display: flex; flex-direction: column; gap: 0.75rem; }

.rb-header {
  display: flex; align-items: center; gap: 0.75rem;
  font-size: 0.7rem; letter-spacing: 0.2em; color: var(--text-muted);
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.rb-icon { color: var(--amber); }

/* Result items */
.ri {
  border: 1px solid var(--border);
  padding: 1rem 1.2rem;
  position: relative; overflow: hidden;
  transition: border-color var(--transition);
}

.ri::before {
  content: ''; position: absolute;
  left: 0; top: 0; bottom: 0; width: 3px;
}

.ri.correct { border-color: rgba(57,224,122,0.2); }
.ri.correct::before { background: var(--green); }

.ri.incorrect { border-color: rgba(245,83,83,0.2); }
.ri.incorrect::before { background: var(--red); }

.ri.partial { border-color: rgba(245,166,35,0.2); }
.ri.partial::before { background: var(--amber); }

.ri-top {
  display: flex; justify-content: space-between;
  align-items: flex-start; gap: 1rem; margin-bottom: 0.5rem;
}

.ri-id {
  font-size: 0.6rem; letter-spacing: 0.15em; color: var(--text-muted);
}

.ri-verdict {
  font-family: var(--font-display); font-size: 0.9rem;
  letter-spacing: 0.1em; white-space: nowrap;
}

.ri-verdict.good { color: var(--green); }
.ri-verdict.bad { color: var(--red); }
.ri-verdict.ok { color: var(--amber); }

.ri-q { font-size: 0.85rem; line-height: 1.5; margin-bottom: 0.5rem; }

.ri-feedback {
  font-size: 0.78rem; color: var(--text-muted); line-height: 1.6;
  font-style: italic; font-family: var(--font-serif);
}

.ri-tags { display: flex; flex-wrap: wrap; gap: 0.35rem; margin-top: 0.6rem; }
.ri-tag {
  background: rgba(245,83,83,0.08);
  border: 1px solid rgba(245,83,83,0.2);
  color: var(--red); padding: 0.1rem 0.5rem;
  font-size: 0.62rem; letter-spacing: 0.1em;
}

/* ── OCR Terminal ────────────────────────────────────────────────── */
.ocr-terminal {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 1rem 1.2rem;
  font-family: var(--font-mono);
  font-size: 0.75rem; color: var(--green);
  line-height: 1.8; white-space: pre-wrap;
  max-height: 160px; overflow-y: auto;
  letter-spacing: 0.02em;
}

.ocr-terminal::-webkit-scrollbar { width: 4px; }
.ocr-terminal::-webkit-scrollbar-track { background: var(--bg); }
.ocr-terminal::-webkit-scrollbar-thumb { background: var(--border2); }

/* ── Feedback Terminal ───────────────────────────────────────────── */
.feedback-terminal {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 1.2rem 1.4rem;
}

.ft-header {
  display: flex; justify-content: space-between;
  font-size: 0.65rem; letter-spacing: 0.2em; color: var(--amber);
  margin-bottom: 0.75rem; padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.ft-blink { animation: blink 1s step-end infinite; }
@keyframes blink { 0%,100% { opacity: 1; } 50% { opacity: 0; } }

.ft-text {
  font-size: 0.85rem; line-height: 1.8; color: var(--text);
  font-family: var(--font-serif); font-style: italic;
}

.ft-grammar {
  font-size: 0.78rem; color: var(--text-muted); margin-top: 0.75rem;
  padding-top: 0.75rem; border-top: 1px solid var(--border);
  letter-spacing: 0.02em;
}

/* ── Results Panel spacing ───────────────────────────────────────── */
.results-panel { gap: 2rem; }

/* ── Footer ──────────────────────────────────────────────────────── */
footer {
  position: relative; z-index: 5;
  border-top: 1px solid var(--border);
  padding: 1rem 2rem;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.6rem; letter-spacing: 0.2em; color: var(--text-dim);
}

/* ── Utilities ───────────────────────────────────────────────────── */
.hidden { display: none !important; }

/* ── Animations ──────────────────────────────────────────────────── */
.step:not(.hidden) .panel {
  animation: panelIn 0.4s ease forwards;
}

@keyframes panelIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ──────────────────────────────────────────────────── */
@media (max-width: 600px) {
  main { padding: 2rem 1rem 4rem; }
  .header-inner { padding: 1rem; }
  .step-num { font-size: 3rem; }
  .options-grid { grid-template-columns: 1fr; }
  .score-dashboard { flex-direction: column; gap: 2rem; }
  .panel { padding: 1.25rem; }
  .mission-strip { gap: 0.75rem; font-size: 0.55rem; }
}