/* Reset & Base */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: "Segoe UI", Arial, sans-serif;
  background-color: #f5f7fa;
  color: #222;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  text-align: center;
}

/* Central container */
.container {
  width: 90%;
  max-width: 900px;
  background: #fff;
  border-radius: 15px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
  padding: 40px;
}

/* Header */
header {
  margin-bottom: 20px;
}

header h1 {
  font-size: 2em;
  color: #1e3a8a;
  margin-bottom: 6px;
}

header h2 {
  font-size: 1.1em;
  color: #555;
  font-weight: normal;
}

/* Sections */
section {
  margin: 25px 0;
}

.info-section p {
  line-height: 1.6;
  font-size: 1em;
  color: #333;
}

/* Upload form */
.upload-section input[type="file"] {
  margin: 12px 0;
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
}

.upload-section button {
  background-color: #2563eb;
  color: white;
  border: none;
  border-radius: 8px;
  padding: 10px 20px;
  font-size: 1em;
  cursor: pointer;
  margin-top: 8px;
}

.upload-section button:hover {
  background-color: #1e40af;
}

/* Graph section */
.plot-container {
  margin-top: 20px;
  display: flex;
  justify-content: center;
}

/* Table section */
.table-container {
  margin-top: 15px;
  display: flex;
  justify-content: center;
  overflow-x: auto;
}

table {
  border-collapse: collapse;
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
}

th, td {
  border: 1px solid #ddd;
  padding: 8px 10px;
}

th {
  background-color: #e5e7eb;
  color: #111;
}

/* Download link */
.download-section a {
  display: inline-block;
  background-color: #059669;
  color: white;
  padding: 10px 16px;
  border-radius: 6px;
  text-decoration: none;
  margin-top: 20px;
}

.download-section a:hover {
  background-color: #047857;
}

/* Footer */
footer {
  margin-top: 40px;
  font-size: 0.9em;
  color: #555;
}