:root {
  --bg: #12161a;
  --panel: #1a1f26;
  --accent: #56c2ff;
  --accent-soft: #a3dfff;
  --text: #f5f7fa;
  --error: #e74c3c;
  --font-main: 'Segoe UI', sans-serif;
  --snow: #d9e7f1;
  --border: #2c2f35;
}
* {
  box-sizing: border-box;
  font-family: var(--font-main);
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  padding-top: 72px;
}
.portal-header {
  position: fixed;
  top: 0;
  width: 100%;
  background-color: var(--panel);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo-group {
  display: flex;
  align-items: center;
  gap: 10px;
}
.header-logo {
  height: 40px;
}
.portal-header h1 {
  font-size: 1.4rem;
  color: var(--accent);
  margin: 0;
}
.portal-header h1 a {
  text-decoration: none;
  color: var(--accent);
}
.nav-links a {
  margin-left: 20px;
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
}
.nav-links a:hover {
  color: var(--accent-soft);
}
footer {
  text-align: center;
  padding: 2rem 1rem;
  font-size: 0.9rem;
  color: #888;
  margin-top: 3rem;
  background-color: transparent;
}
.session-container {
  max-width: 1100px;
  margin: 2rem auto;
  padding: 2rem;
  background: var(--panel);
  border-radius: 12px;
  box-shadow: 0 0 15px rgba(0,0,0,0.25);
  animation: fadeIn 0.5s ease-in;
}
.session-container h2 {
  font-size: 1.8rem;
  margin-bottom: 1.5rem;
  color: var(--accent);
  text-shadow: 0 0 2px rgba(0,0,0,0.3);
}
.session-table {
  width: 100%;
  border-collapse: collapse;
  color: var(--text);
  font-size: 0.95rem;
}
.session-table th,
.session-table td {
  padding: 0.8rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
.session-table th {
  background-color: var(--panel);
  font-weight: 600;
  color: var(--accent);
}
.session-table tr:nth-child(even) {
  background-color: #181d23;
}
.session-table .action-cell {
  text-align: right;
  vertical-align: middle;
  white-space: nowrap;
}
.session-table .delete {
  background-color: var(--error);
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 0.4rem 0.75rem;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background-color 0.2s ease;
}
.session-table .delete:hover {
  background-color: #c0392b;
}
.session-table form {
  margin: 0;
}
.error {
  background: rgba(231, 76, 60, 0.15);
  border: 1px solid var(--error);
  padding: 0.75rem 1rem;
  border-radius: 6px;
  color: var(--error);
  margin-bottom: 1rem;
  text-align: center;
}
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
@media screen and (max-width: 768px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }
  .nav-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
  }
  .nav-links a {
    margin-left: 0;
    margin-right: 15px;
  }
  .session-table th,
  .session-table td {
    font-size: 0.85rem;
    word-break: break-word;
  }
  .session-container {
    padding: 1.2rem;
  }
}