* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #f5f5f5;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

header {
  text-align: center;
  margin-bottom: 40px;
  padding: 30px 0;
  background: white;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

header h1 {
  color: #2c3e50;
  margin-bottom: 10px;
  font-size: 2.5em;
}

header p {
  color: #7f8c8d;
  font-size: 1.2em;
}

.search-section {
  background: white;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  margin-bottom: 30px;
}

.input-group {
  display: flex;
  gap: 10px;
  max-width: 600px;
  margin: 0 auto;
}

input[type="text"] {
  flex: 1;
  padding: 15px;
  border: 2px solid #ddd;
  border-radius: 5px;
  font-size: 16px;
  transition: border-color 0.3s;
}

input[type="text"]:focus {
  outline: none;
  border-color: #3498db;
}

button {
  padding: 15px 30px;
  background-color: #3498db;
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 16px;
  cursor: pointer;
  transition: background-color 0.3s;
}

button:hover {
  background-color: #2980b9;
}

.loading {
  text-align: center;
  padding: 40px;
  background: white;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid #f3f3f3;
  border-top: 4px solid #3498db;
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto 20px;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.results {
  background: white;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  overflow: hidden;
}

.result-header {
  background: #3498db;
  color: white;
  padding: 20px 30px;
}

.result-header h2 {
  margin-bottom: 10px;
}

.result-summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.paper-list {
  padding: 30px;
}

.paper-item {
  padding: 15px;
  border-left: 4px solid #3498db;
  background: #f8f9fa;
  margin-bottom: 15px;
  border-radius: 0 5px 5px 0;
}

.paper-title {
  font-weight: bold;
  color: #2c3e50;
  margin-bottom: 5px;
}

.paper-venue {
  color: #7f8c8d;
  font-size: 0.9em;
}

.error {
  background: #e74c3c;
  color: white;
  padding: 20px;
  border-radius: 10px;
  text-align: center;
}

.hidden {
  display: none;
}

.no-papers {
  text-align: center;
  color: #7f8c8d;
  font-style: italic;
  padding: 40px;
}

@media (max-width: 768px) {
  .input-group {
    flex-direction: column;
  }

  .result-summary {
    flex-direction: column;
    align-items: flex-start;
  }

  header h1 {
    font-size: 2em;
  }
}