:root {
  --bg: #091015;
  --bg-soft: #0e171d;
  --panel: rgba(9, 18, 24, 0.86);
  --panel-strong: rgba(7, 14, 18, 0.94);
  --line: rgba(133, 170, 178, 0.2);
  --line-strong: rgba(133, 170, 178, 0.4);
  --text: #edf4f4;
  --muted: #9ab0ae;
  --accent: #7ce0c1;
  --accent-strong: #43c698;
  --warn: #f9c56a;
  --error: #ff8b80;
  --shadow: 0 18px 56px rgba(0, 0, 0, 0.3);
  --radius: 20px;
  --mono: "IBM Plex Mono", "SFMono-Regular", Menlo, Consolas, monospace;
  --sans: "IBM Plex Sans", "Segoe UI", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  color: var(--text);
  font-family: var(--sans);
  background:
    radial-gradient(circle at top left, rgba(124, 224, 193, 0.14), transparent 28%),
    radial-gradient(circle at top right, rgba(249, 197, 106, 0.14), transparent 26%),
    linear-gradient(180deg, #081015 0%, #091015 50%, #081116 100%);
  background-attachment: fixed;
}

.shell {
  width: min(1360px, calc(100vw - 32px));
  margin: 24px auto 40px;
}

.hero,
.card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.hero {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  padding: 24px 26px;
  margin-bottom: 16px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 4rem);
  line-height: 0.95;
  letter-spacing: -0.05em;
}

.tagline {
  margin: 10px 0 0;
  color: var(--muted);
}

.auth-bar {
  display: flex;
  align-items: flex-start;
  justify-content: flex-end;
  gap: 12px;
  min-width: 280px;
  color: var(--muted);
  font-size: 14px;
}

.grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}

.stack {
  display: grid;
  gap: 16px;
}

.card {
  padding: 18px;
}

.card-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 14px;
}

.card-head h2 {
  margin: 0;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.card-head p {
  margin: 3px 0 0;
  color: var(--muted);
  font-size: 13px;
}

textarea,
input[type="text"],
input[type="number"] {
  width: 100%;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  background: rgba(4, 10, 12, 0.82);
  color: var(--text);
  font: inherit;
  outline: none;
  transition: border-color 0.18s ease, transform 0.18s ease;
}

textarea {
  min-height: 260px;
  resize: vertical;
  padding: 14px 15px;
  line-height: 1.55;
}

input[type="text"],
input[type="number"] {
  padding: 13px 14px;
}

textarea:focus,
input:focus {
  border-color: var(--line-strong);
  transform: translateY(-1px);
}

.actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 12px;
}

.button {
  appearance: none;
  border: none;
  border-radius: 999px;
  padding: 11px 16px;
  background: var(--accent);
  color: #03140f;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.18s ease, filter 0.18s ease, border-color 0.18s ease;
}

.button:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
}

.button.secondary,
.button.ghost,
.file-button {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.button.ghost {
  background: transparent;
}

.file-button input {
  display: none;
}

.file-chip {
  color: var(--muted);
  font-size: 13px;
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-top: 14px;
}

.stat {
  padding: 12px 13px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.stat .k {
  display: block;
  color: var(--muted);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 5px;
}

.stat .v {
  font-size: 1.05rem;
  font-weight: 600;
}

.preview-list,
.trace-list {
  display: grid;
  gap: 10px;
}

.section-card,
.trace-item {
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.07);
  background: rgba(255, 255, 255, 0.03);
  padding: 13px 14px;
}

.section-card strong {
  display: block;
  margin-bottom: 8px;
  font-size: 13px;
}

.section-card p {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  white-space: pre-wrap;
  word-break: break-word;
  font-family: var(--mono);
}

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.pill {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 7px 11px;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted);
  font-size: 12px;
  letter-spacing: 0.03em;
}

.advanced {
  margin-top: 12px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.02);
}

.advanced summary {
  cursor: pointer;
  list-style: none;
  padding: 12px 14px;
  font-size: 13px;
  color: var(--muted);
  user-select: none;
}

.advanced summary::-webkit-details-marker {
  display: none;
}

.option-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  padding: 0 14px 14px;
}

.option-grid label {
  display: grid;
  gap: 6px;
}

.option-grid span {
  color: var(--muted);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.skills-line {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 13px;
}

code {
  font-family: var(--mono);
  font-size: 0.95em;
}

.banner {
  min-height: 20px;
  margin-top: 10px;
  font-size: 13px;
  color: var(--muted);
}

.banner.info {
  color: var(--accent);
}

.banner.error {
  color: var(--error);
}

.answer-box {
  min-height: 120px;
  border-radius: 16px;
  border: 1px solid rgba(124, 224, 193, 0.22);
  background: rgba(124, 224, 193, 0.06);
  padding: 15px;
}

.answer-text,
.trace-body {
  white-space: pre-wrap;
  word-break: break-word;
  line-height: 1.65;
}

.placeholder,
.empty-state {
  color: var(--muted);
}

.trace-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 8px;
}

.trace-title {
  font-size: 13px;
  font-weight: 600;
}

.trace-meta {
  color: var(--muted);
  font-size: 12px;
}

.trace-kind {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  padding: 4px 8px;
  border-radius: 999px;
  margin-right: 8px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.09em;
}

.kind-model {
  background: rgba(124, 224, 193, 0.14);
  color: var(--accent);
}

.kind-tool {
  background: rgba(140, 196, 255, 0.14);
  color: #8cc4ff;
}

.kind-sub {
  background: rgba(196, 140, 255, 0.14);
  color: #c28cff;
}

.kind-final {
  background: rgba(249, 197, 106, 0.18);
  color: var(--warn);
}

.kind-error {
  background: rgba(255, 139, 128, 0.14);
  color: var(--error);
}

@media (max-width: 980px) {
  .grid {
    grid-template-columns: 1fr;
  }

  .hero {
    flex-direction: column;
    align-items: flex-start;
  }

  .auth-bar {
    min-width: 0;
    justify-content: flex-start;
  }
}

@media (max-width: 640px) {
  .shell {
    width: min(100vw - 20px, 100%);
    margin: 10px auto 24px;
  }

  .hero,
  .card {
    padding: 15px;
    border-radius: 18px;
  }

  .stats,
  .option-grid {
    grid-template-columns: 1fr 1fr;
  }

  .actions {
    align-items: stretch;
  }

  .button,
  .file-button {
    width: 100%;
    justify-content: center;
    text-align: center;
  }
}