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

body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  background: #0f172a;
  color: #e2e8f0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: #60a5fa;
}

header.app-header {
  padding: 1.5rem 1rem;
  text-align: center;
  background: #1e293b;
  border-bottom: 1px solid rgba(148, 163, 184, 0.4);
}

header.app-header h1 {
  margin: 0;
  font-size: 1.75rem;
}

header.app-header .note {
  margin: 0.5rem 0 0;
  font-size: 0.95rem;
  color: #94a3b8;
}

header.app-header .note .mono {
  font-family: "Cascadia Mono", "Consolas", monospace;
  color: #cbd5f5;
}

main {
  flex: 1;
  width: min(1200px, 80vw);
  margin: 2rem auto 3rem;
}

.uploader {
  margin-bottom: 1.5rem;
}

.drop-zone {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border: 2px dashed rgba(148, 163, 184, 0.5);
  border-radius: 12px;
  padding: 2.5rem 1rem;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
  color: #cbd5f5;
  text-align: center;
  background: rgba(15, 23, 42, 0.6);
}

.drop-zone:hover,
.drop-zone.dragging {
  border-color: #60a5fa;
  background: rgba(37, 99, 235, 0.15);
}

.drop-zone .prompt {
  font-size: 1.1rem;
  margin-bottom: 0.75rem;
}

.drop-zone .prompt code {
  background: rgba(71, 85, 105, 0.4);
  padding: 0.15rem 0.4rem;
  border-radius: 6px;
}

.drop-zone .or {
  margin: 0.5rem 0;
  font-size: 0.9rem;
  color: #94a3b8;
}

.drop-zone .button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1.2rem;
  border-radius: 999px;
  background: linear-gradient(135deg, #38bdf8, #6366f1);
  color: #0f172a;
  font-weight: 600;
  letter-spacing: 0.5px;
}

#file-input {
  display: none;
}

.hint {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: #94a3b8;
  text-align: center;
}

.messages {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.session-stats {
  margin: 0.5rem 0 0;
}

.session-counter {
  margin: 0;
  font-size: 0.95rem;
  color: #cbd5f5;
  background: rgba(15, 23, 42, 0.7);
  border-radius: 10px;
  padding: 0.65rem 0.85rem;
  border: 1px solid rgba(148, 163, 184, 0.3);
}

.message {
  padding: 0.85rem 1rem;
  border-radius: 8px;
  border-left: 4px solid transparent;
  background: rgba(15, 23, 42, 0.7);
  color: #e2e8f0;
  font-size: 0.95rem;
  line-height: 1.4;
}

.message.warning {
  border-left-color: #fbbf24;
  background: rgba(250, 204, 21, 0.12);
  color: #fde68a;
}

.message.error {
  border-left-color: #f87171;
  background: rgba(248, 113, 113, 0.12);
  color: #fecaca;
}

.message.info {
  border-left-color: #38bdf8;
  background: rgba(56, 189, 248, 0.12);
  color: #bae6fd;
}

.hidden {
  display: none !important;
}

.results {
  margin-top: 2rem;
  padding: 1.5rem;
  border-radius: 16px;
  background: rgba(15, 23, 42, 0.65);
  border: 1px solid rgba(148, 163, 184, 0.25);
  box-shadow: 0 20px 45px rgba(15, 23, 42, 0.35);
  backdrop-filter: blur(12px);
}

.summary {
  margin-bottom: 1.5rem;
}

.summary h2,
.feedback h2 {
  margin: 0 0 0.75rem;
  font-size: 1.2rem;
  color: #cbd5f5;
}

.score-line,
.cutout-line {
  margin: 0.25rem 0;
  font-size: 1.05rem;
  color: #e2e8f0;
}

.feedback {
  margin-top: 1.25rem;
}

.feedback-log {
  background: rgba(6, 12, 25, 0.85);
  border-radius: 12px;
  padding: 1rem;
  font-family: "Cascadia Mono", "Consolas", "SFMono-Regular", monospace;
  font-size: 0.9rem;
  line-height: 1.55;
  color: #f8fafc;
  max-height: 420px;
  overflow-y: auto;
  white-space: pre-wrap;
}

.diff-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.diff-table th,
.diff-table td {
  border: 1px solid rgba(148, 163, 184, 0.25);
  padding: 0.5rem;
  vertical-align: top;
  text-align: left;
}

.diff-table th {
  background: rgba(30, 41, 59, 0.6);
  color: #cbd5f5;
}

.diff-row-mismatch {
  background: rgba(248, 113, 113, 0.1);
}

.diff-row-mismatch td {
  color: #fecaca;
}

.feedback-log::-webkit-scrollbar {
  width: 8px;
}

.feedback-log::-webkit-scrollbar-track {
  background: rgba(30, 41, 59, 0.6);
}

.feedback-log::-webkit-scrollbar-thumb {
  background: rgba(148, 163, 184, 0.6);
  border-radius: 4px;
}

footer {
  padding: 1.25rem 0;
  text-align: center;
  font-size: 0.85rem;
  color: #94a3b8;
}