:root {
  --bg: #f2f5fb;
  --text: #172033;
  --muted: #5f6b85;
  --card: #ffffff;
  --primary: #315efb;
  --primary-soft: #e7edff;
  --border: #d8e1f2;
  --shadow: 0 10px 28px rgba(26, 45, 83, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--text);
  background: radial-gradient(circle at top right, #e9f0ff 0, var(--bg) 45%);
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.page {
  max-width: 1180px;
  margin: 0 auto;
  padding: 28px 24px 40px;
}

h1,
h2,
h3 {
  margin: 0 0 10px;
}

p {
  margin: 6px 0;
}

.hero {
  margin-bottom: 14px;
}

.hero h1 {
  font-size: 38px;
  letter-spacing: 0.3px;
}

.hero-desc {
  color: var(--muted);
  font-size: 16px;
}

/* ── Mode Tabs ────────────────────────────────────── */

.mode-tabs {
  display: flex;
  gap: 0;
  margin-bottom: 18px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border);
  width: fit-content;
}

.mode-tab {
  border: none;
  background: #f7faff;
  color: var(--muted);
  padding: 11px 28px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.mode-tab:hover {
  background: #edf2ff;
}

.mode-tab-active {
  background: linear-gradient(180deg, #4f77ff 0%, #315efb 100%);
  color: #fff;
}

/* ── Cards ────────────────────────────────────────── */

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 18px;
  margin-bottom: 18px;
  box-shadow: var(--shadow);
}

.upload-grid,
.range-grid,
.dataset-grid {
  display: grid;
  gap: 12px;
}

.upload-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.upload-item-wide {
  grid-column: 1 / -1;
}

.range-grid {
  grid-template-columns: repeat(2, minmax(180px, 240px));
  margin-bottom: 14px;
}

label span {
  display: inline-block;
  margin-bottom: 7px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
}

input[type="number"],
input[type="file"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  font-size: 14px;
}

input[type="number"]:focus {
  outline: none;
  border-color: #9db2ff;
  box-shadow: 0 0 0 3px rgba(49, 94, 251, 0.12);
}

.card-title {
  font-size: 34px;
  letter-spacing: 0.4px;
}

.sub-title {
  margin-top: 4px;
  font-size: 26px;
}

.upload-item {
  border: 1px solid #d9e4ff;
  border-radius: 12px;
  padding: 14px;
  background: linear-gradient(180deg, #f9fbff 0%, #f4f7ff 100%);
}

.upload-title {
  font-size: 15px;
  color: var(--muted);
  margin: 0 0 12px;
  font-weight: 600;
}

.file-input {
  display: none !important;
}

.file-button {
  display: inline-flex !important;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  border: 1px solid var(--primary);
  background: linear-gradient(180deg, #f1f5ff 0%, #e5ecff 100%);
  color: var(--primary);
  padding: 9px 14px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.file-button:hover {
  background: #dbe6ff;
  transform: translateY(-1px);
}

.file-name {
  margin-top: 10px;
  font-size: 13px;
  color: var(--text);
  line-height: 1.4;
  min-height: 18px;
}

.file-list {
  margin-top: 6px;
  max-height: 130px;
  overflow: auto;
  padding-right: 4px;
}

.primary {
  border: none;
  background: linear-gradient(180deg, #4f77ff 0%, #315efb 100%);
  color: #fff;
  border-radius: 10px;
  padding: 10px 22px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 10px 18px rgba(49, 94, 251, 0.26);
}

.action-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.primary:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  box-shadow: none;
}

.error {
  color: #b91c1c;
  margin-top: 10px;
}

/* ── Charts ───────────────────────────────────────── */

.chart {
  width: 100%;
  height: 480px;
  border: 1px solid #e6ebf7;
  border-radius: 12px;
  background: #fff;
  padding: 8px;
}

.chart-tall {
  height: 560px;
}

/* ── Curve Filters ────────────────────────────────── */

.curve-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 14px;
}

.curve-actions {
  display: inline-flex;
  gap: 6px;
  margin-right: 8px;
  padding: 4px;
  border-radius: 999px;
  border: 1px solid #d5deef;
  background: #f7faff;
}

.ghost-button {
  border: 0;
  background: transparent;
  color: #40506c;
  border-radius: 999px;
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.ghost-button:hover {
  transform: translateY(-1px);
}

.ghost-button-primary {
  background: #e8efff;
  color: #2f55d4;
}

.ghost-button-muted {
  background: #ffffff;
  color: #334155;
  border: 1px solid #e2e8f6;
}

.curve-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid #d5deef;
  border-radius: 999px;
  padding: 7px 11px;
  background: #fdfefe;
  color: var(--text);
  font-size: 14px;
}

.curve-item input[type="checkbox"] {
  width: 14px;
  height: 14px;
}

/* ── Dataset Results ──────────────────────────────── */

.dataset-grid {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.dataset-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px;
  background: #fcfdff;
}

.dataset-card h3 {
  font-size: 24px;
  margin-bottom: 10px;
}

.dataset-card p {
  color: #2c374e;
}

.stat-section {
  margin-top: 12px;
  border-top: 1px dashed #dbe5fa;
  padding-top: 10px;
}

.stat-section h4 {
  margin: 0 0 8px;
  font-size: 15px;
  color: #233462;
}

.peak-detail-wrap {
  margin-top: 12px;
  border-top: 1px dashed #dbe5fa;
  padding-top: 10px;
}

.peak-detail-wrap h4 {
  margin: 0 0 8px;
  font-size: 14px;
  color: #233462;
}

.peak-detail-item {
  background: #f5f8ff;
  border: 1px solid #dde7ff;
  border-radius: 10px;
  padding: 8px 10px;
  margin-bottom: 8px;
}

.mc-item {
  background: #fff5f5;
  border-color: #ffcdd2;
}

@media (max-width: 900px) {
  .hero h1 {
    font-size: 30px;
  }
  .card-title {
    font-size: 28px;
  }
  .sub-title {
    font-size: 22px;
  }
  .range-grid {
    grid-template-columns: 1fr;
  }
  .chart-tall {
    height: 440px;
  }
}