:root {
  --app-bg: #f4f7fb;
  --app-card: #ffffff;
  --app-ink: #1f2937;
  --app-muted: #667085;
  --app-line: #e5eaf2;
  --app-primary: #2f6fed;
  --app-primary-dark: #2458c7;
  --app-soft: #eef4ff;
  --app-radius: 22px;
  --app-shadow: 0 18px 50px rgba(31, 41, 55, 0.10);
}

body {
  min-height: 100vh;
  color: var(--app-ink);
  background:
    radial-gradient(circle at top left, rgba(47, 111, 237, 0.12), transparent 34rem),
    linear-gradient(180deg, #fbfdff 0%, var(--app-bg) 42%, #eef3f9 100%);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

a {
  color: var(--app-primary);
  text-decoration: none;
}

a:hover {
  color: var(--app-primary-dark);
  text-decoration: underline;
}

.bd-navbar {
  margin: 14px auto 0;
  width: min(1120px, calc(100% - 24px));
  border: 1px solid rgba(229, 234, 242, 0.9);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.84);
  box-shadow: 0 10px 30px rgba(31, 41, 55, 0.08);
  backdrop-filter: blur(14px);
}

.nav-tabs {
  gap: 6px;
  border-bottom: 0;
}

.nav-tabs .nav-link,
.nav .nav-link {
  border: 0;
  border-radius: 999px;
  color: var(--app-muted);
  font-weight: 600;
}

.nav-tabs .nav-link.active,
.nav .nav-link:hover {
  color: var(--app-primary);
  background: var(--app-soft);
}

.page-shell {
  padding-top: 30px;
  padding-bottom: 22px;
}

.content-card {
  max-width: 920px;
  margin: 0 auto;
  padding: clamp(22px, 4vw, 42px);
  border: 1px solid rgba(229, 234, 242, 0.9);
  border-radius: var(--app-radius);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--app-shadow);
}

.page-footer {
  max-width: 920px;
  margin: 0 auto 28px;
  padding: 0 18px;
  color: var(--app-muted);
  font-size: 0.92rem;
}

.upload-panel,
.file-panel {
  display: grid;
  gap: 22px;
}

.page-kicker {
  margin-bottom: 8px;
  color: var(--app-primary);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.page-title {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.1rem);
  font-weight: 800;
  letter-spacing: -0.045em;
}

.page-subtitle {
  max-width: 620px;
  margin: 12px 0 0;
  color: var(--app-muted);
  line-height: 1.7;
}

.upload-form {
  display: grid;
  gap: 18px;
}

.form-label {
  color: #344054;
  font-weight: 700;
}

.form-control {
  border-color: var(--app-line);
  border-radius: 14px;
  padding: 0.78rem 0.95rem;
}

.form-control:focus {
  border-color: rgba(47, 111, 237, 0.55);
  box-shadow: 0 0 0 0.22rem rgba(47, 111, 237, 0.14);
}

.form-text {
  color: var(--app-muted);
}

.btn-primary {
  border-color: var(--app-primary);
  border-radius: 999px;
  background: var(--app-primary);
  box-shadow: 0 12px 24px rgba(47, 111, 237, 0.22);
  font-weight: 800;
}

.btn-primary:hover {
  border-color: var(--app-primary-dark);
  background: var(--app-primary-dark);
}

.upload-submit {
  width: 100%;
  padding: 0.86rem 1.2rem;
}

.alert {
  border-radius: 16px;
}

.table-responsive {
  border: 1px solid var(--app-line);
  border-radius: 18px;
  overflow: hidden;
}

.table {
  margin-bottom: 0;
  vertical-align: middle;
}

.table thead th {
  background: #f7f9fc;
  color: #475467;
  font-size: 0.88rem;
}

.file-link {
  font-weight: 700;
}

.empty-state {
  padding: 32px;
  border: 1px dashed #cad5e5;
  border-radius: 18px;
  color: var(--app-muted);
  background: #f8fbff;
  text-align: center;
}

@media (max-width: 576px) {
  .bd-navbar {
    border-radius: 24px;
  }

  .content-card {
    padding: 22px 18px;
  }
}