:root {
  --bg: #f7f9fc;
  --card: #fff;
  --accent: #2b6cb0;
  --text: #0f1720;
}
* {
  box-sizing: border-box;
}
body {
  font-family: Inter, system-ui, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  padding: 24px;
}
.container {
  max-width: 640px;
  margin: 0 auto;
}
h1 {
  margin: 0 0 8px;
}
p {
  margin: 8px 0 16px;
}
form {
  display: flex;
  gap: 8px;
  align-items: center;
  margin-bottom: 16px;
}
input[type="text"] {
  flex: 1;
  padding: 10px;
  border: 1px solid #d1d5db;
  border-radius: 6px;
}
button {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 10px 14px;
  border-radius: 6px;
  cursor: pointer;
}
.card {
  background: var(--card);
  padding: 16px;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(12, 15, 20, 0.06);
}
.hidden {
  display: none;
}
#message {
  padding: 12px;
  border-radius: 6px;
  margin-bottom: 12px;
}
#message.error {
  background: #ffe7e7;
  color: #7a1212;
}
#message.info {
  background: #e7f2ff;
  color: #0b4b7a;
}
footer {
  margin-top: 20px;
  font-size: 14px;
}

.subjects-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 8px;
}
.subjects-table th,
.subjects-table td {
  border: 1px solid #e6e9ef;
  padding: 8px;
  text-align: left;
}
.subjects-table th {
  background: #f1f5f9;
  font-weight: 600;
}
.subjects-table td {
  background: #fff;
}
.subjects-table tr:nth-child(even) td {
  background: #fbfdff;
}
.subjects-table-wrap {
  overflow: auto;
}
.subjects-table caption {
  caption-side: top;
  text-align: left;
  font-weight: 600;
  margin-bottom: 6px;
}

@media (max-width: 420px) {
  body {
    padding: 14px;
  }
  form {
    flex-direction: column;
    align-items: stretch;
  }
  button {
    width: 100%;
  }
}