:root {
  --ink: #15231c;
  --ink-soft: #3a4a42;
  --paper: #f3efe6;
  --panel: #fffdf8;
  --line: #c9c0b0;
  --accent: #0f6b5c;
  --accent-deep: #0a4a40;
  --warn: #9a4d1c;
  --ok: #1f6b3a;
  --shadow: 0 18px 40px rgba(21, 35, 28, 0.08);
  --font-sans: "IBM Plex Sans", "Segoe UI", sans-serif;
  --font-display: "Noto Serif SC", "Songti SC", serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  color: var(--ink);
  font-family: var(--font-sans);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(15, 107, 92, 0.12), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(154, 77, 28, 0.08), transparent 50%),
    linear-gradient(180deg, #ebe4d6 0%, var(--paper) 45%, #e7e0d2 100%);
}

.bg-grid {
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.35;
  background-image:
    linear-gradient(rgba(21, 35, 28, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(21, 35, 28, 0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at center, #000 40%, transparent 85%);
}

.shell {
  position: relative;
  width: min(980px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 3.5rem 0 4rem;
}

.hero {
  margin-bottom: 2.25rem;
  animation: rise 0.7s ease both;
}

.brand {
  margin: 0 0 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent);
}

.hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.8rem, 4vw, 2.55rem);
  line-height: 1.2;
  letter-spacing: 0.02em;
}

.lede {
  margin: 0.9rem 0 0;
  max-width: 42rem;
  color: var(--ink-soft);
  line-height: 1.7;
  font-size: 1.02rem;
}

.lede strong {
  color: var(--accent-deep);
  font-weight: 600;
}

.upload-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  align-items: stretch;
  margin-bottom: 1.5rem;
  animation: rise 0.8s ease 0.08s both;
}

.dropzone {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  min-height: 190px;
  padding: 1.35rem 1.4rem;
  border: 1.5px dashed var(--line);
  border-radius: 4px;
  background: color-mix(in srgb, var(--panel) 92%, white);
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: border-color 0.2s, transform 0.2s, background 0.2s;
}

.dropzone:hover,
.dropzone:focus-within {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.dropzone.dragover {
  border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 8%, var(--panel));
}

.dropzone.ready {
  border-style: solid;
  border-color: color-mix(in srgb, var(--accent) 55%, var(--line));
}

.slot {
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--warn);
  font-weight: 600;
}

.title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
}

.hint {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.fname {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid color-mix(in srgb, var(--line) 70%, transparent);
  font-size: 0.9rem;
  color: var(--ink);
  word-break: break-all;
}

.flow-mark {
  display: grid;
  place-items: center;
  width: 2.5rem;
}

.flow-mark span {
  display: block;
  width: 2rem;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  position: relative;
}

.flow-mark span::after {
  content: "";
  position: absolute;
  right: -2px;
  top: 50%;
  width: 8px;
  height: 8px;
  border-right: 2px solid var(--accent);
  border-top: 2px solid var(--accent);
  transform: translateY(-50%) rotate(45deg);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
  animation: rise 0.85s ease 0.14s both;
}

.btn {
  appearance: none;
  border: 0;
  border-radius: 3px;
  padding: 0.85rem 1.35rem;
  font: inherit;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: transform 0.15s, opacity 0.15s, background 0.15s;
}

.btn:disabled {
  opacity: 0.42;
  cursor: not-allowed;
}

.btn:not(:disabled):hover {
  transform: translateY(-1px);
}

.btn.primary {
  background: var(--accent);
  color: #f7fffC;
}

.btn.primary:not(:disabled):hover {
  background: var(--accent-deep);
}

.btn.ghost {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--ink);
}

.btn.ghost:not(:disabled):hover {
  background: var(--ink);
  color: var(--paper);
}

.status {
  min-height: 1.5rem;
  color: var(--ink-soft);
  font-size: 0.95rem;
  animation: rise 0.9s ease 0.18s both;
}

.status.error { color: #8a1f1f; }
.status.ok { color: var(--ok); }

.report {
  margin-top: 1.75rem;
  padding: 1.35rem 1.4rem;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 4px;
  box-shadow: var(--shadow);
  animation: rise 0.5s ease both;
}

.report h2 {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-size: 1.2rem;
}

.report-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1.1rem;
  margin-bottom: 1rem;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.55rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #faf7f0;
}

.sheet-card {
  border-top: 1px solid color-mix(in srgb, var(--line) 80%, transparent);
  padding: 0.85rem 0;
}

.sheet-card:first-child { border-top: 0; }

.sheet-card h3 {
  margin: 0 0 0.4rem;
  font-size: 0.98rem;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.tag {
  font-size: 0.78rem;
  padding: 0.18rem 0.45rem;
  border-radius: 2px;
  background: color-mix(in srgb, var(--accent) 12%, white);
  color: var(--accent-deep);
}

.tag.muted {
  background: #eee8dc;
  color: #6b6356;
}

@keyframes rise {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 760px) {
  .upload-grid {
    grid-template-columns: 1fr;
  }
  .flow-mark {
    width: 100%;
    height: 1.5rem;
  }
  .flow-mark span {
    width: 2px;
    height: 1.2rem;
    background: linear-gradient(180deg, transparent, var(--accent), transparent);
  }
  .flow-mark span::after {
    right: 50%;
    top: auto;
    bottom: -2px;
    transform: translateX(50%) rotate(135deg);
  }
}