body {
  font-family: 'Verdana', sans-serif;
  background-color: #f7f3ed;
  color: #333;
  margin: 0;
  padding: 0;
  text-align: center;
  font-size: 1.1em;
  letter-spacing: 0.8px;
}

a {
  color: inherit;
}

.system-shell {
  max-width: 780px;
  margin: 0 auto;
  padding: 20px;
  background: #f7f3ed;
  min-height: 100vh;
  box-shadow: 0 0 20px rgba(0, 0, 0, 0.05);
  border: 1px solid #e0d0b0;
  box-sizing: border-box;
}

.system-nav {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.system-nav-bottom {
  margin-top: 20px;
}

.system-nav-link {
  display: inline-block;
  padding: 10px 14px;
  background: #d4e6f1;
  color: #2c3e50;
  text-decoration: none;
  border-radius: 8px;
  border: 3px solid #a9cce3;
  box-shadow: 0 4px 0 #a9cce3;
  font-weight: bold;
}

.system-nav-link:active {
  transform: translateY(4px);
  box-shadow: 0 0 0 #a9cce3;
}

.system-panel {
  border: 2px solid #e0d0b0;
  border-radius: 10px;
  background: #f7f3ed;
  padding: 18px;
  text-align: left;
  margin-bottom: 18px;
}

.system-panel h2,
.system-panel h3 {
  color: #2c3e50;
  margin-top: 0;
}

.system-message {
  border-radius: 10px;
  padding: 14px 16px;
  margin-bottom: 18px;
  text-align: left;
  border: 2px solid #e0d0b0;
}

.system-message-error {
  background: #fbe3e0;
  border-color: #ec7063;
  color: #780000;
}

.system-message-success {
  background: #dff3e7;
  border-color: #a9dfbf;
  color: #1f6d45;
}

.system-debug {
  white-space: pre-wrap;
  margin-top: 12px;
  padding: 12px;
  background: #fff;
  border-radius: 8px;
  border: 1px dashed #b8a892;
}

.system-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.system-field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.system-field label {
  font-weight: bold;
}

.system-input {
  font-size: 1.1em;
  padding: 12px;
  border: 2px solid #b8a892;
  border-radius: 5px;
  color: #333;
  box-sizing: border-box;
  width: 100%;
  background: #fff;
}

.system-input-uppercase {
  text-transform: uppercase;
}

.system-help {
  margin: 0;
  font-size: 0.9em;
  color: #666;
}

.system-login-layout {
  display: grid;
  gap: 20px;
  text-align: center;
}

.system-login-name {
  width: 80%;
  margin: 0 auto 20px auto;
  text-align: center;
  font-size: 20px;
}

.system-pin-display {
  font-size: 24px;
  padding: 12px;
  letter-spacing: 5px;
  min-height: 30px;
  text-align: center;
}

.system-login-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(70px, 1fr));
  gap: 12px;
  margin: 0 auto;
  max-width: 280px;
}

.system-key {
  background: transparent;
  border: 0;
  padding: 0;
  cursor: pointer;
}

.system-key-box {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  min-height: 76px;
  background: #e6e0d8;
  border-radius: 5px;
  font-size: 34px;
  border: 3px solid #b8a892;
  color: #333;
  box-shadow: 0 4px 0 #b8a892;
}

.system-key:active .system-key-box {
  background: #d8d0c8;
  transform: translateY(4px);
  box-shadow: 0 0 0 #b8a892;
}

.system-button-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  width: 100%;
  padding: 15px;
  background: #d4e6f1;
  color: #2c3e50;
  text-decoration: none;
  font-size: 1.05em;
  border-radius: 8px;
  border: 3px solid #a9cce3;
  cursor: pointer;
  box-sizing: border-box;
  font-weight: bold;
  text-align: center;
  box-shadow: 0 4px 0 #a9cce3;
}

.btn:active {
  transform: translateY(4px);
  box-shadow: 0 0 0 #a9cce3;
}

.btn-secondary {
  background: #fdf2e9;
  border-color: #eb984e;
  box-shadow: 0 4px 0 #eb984e;
  color: #a0522d;
}

.btn-danger {
  background: #f5b7b1;
  border-color: #ec7063;
  box-shadow: 0 4px 0 #ec7063;
  color: #780000;
}

.btn-small {
  max-width: 220px;
}

.btn[disabled] {
  opacity: 0.7;
  cursor: not-allowed;
}

.system-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.system-card {
  border: 2px solid #e0d0b0;
  border-radius: 10px;
  background: #fff9f1;
  padding: 18px;
  text-align: left;
}

.system-card h3 {
  margin-top: 0;
}

.system-card-icon {
  font-size: 2em;
  color: #a0522d;
}

.system-card-link {
  margin-top: 12px;
}

.system-profile-grid {
  display: grid;
  gap: 12px;
}

.system-data-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid #eadcc4;
}

.system-data-row strong {
  color: #2c3e50;
}

.system-admin-list {
  display: grid;
  gap: 14px;
}

.system-admin-card {
  border: 2px solid #e0d0b0;
  border-radius: 10px;
  background: #fff9f1;
  padding: 16px;
}

.system-admin-card-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.system-checkbox {
  display: flex;
  gap: 10px;
  align-items: center;
}

.system-checkbox input {
  width: 20px;
  height: 20px;
}

@media (max-width: 640px) {
  .system-shell {
    padding: 14px;
  }

  .system-nav {
    width: 100%;
  }

  .system-nav-link {
    width: 100%;
    box-sizing: border-box;
    text-align: center;
  }

  .system-data-row {
    flex-direction: column;
  }
}