/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

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

/* Header */
.header {
    text-align: center;
    margin-bottom: 40px;
    color: white;
}

.header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.header p {
    font-size: 1.1rem;
    opacity: 0.9;
    font-weight: 300;
}

/* Main content */
.main-content {
    display: grid;
    gap: 30px;
    grid-template-columns: 1fr;
}

@media (min-width: 768px) {
    .main-content {
        grid-template-columns: 1fr 1fr;
    }
}

/* Sections */
.input-section,
.results-section,
.sessions-section {
    background: white;
    border-radius: 16px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    backdrop-filter: blur(10px);
}

.sessions-section {
    grid-column: 1 / -1;
}

/* Section headers */
h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: #2d3748;
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Form elements */
.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #4a5568;
}

input[type="text"],
textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s ease;
    background: #f7fafc;
}

input[type="text"]:focus,
textarea:focus {
    outline: none;
    border-color: #667eea;
    background: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

textarea {
    resize: vertical;
    min-height: 120px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

.btn-secondary {
    background: #48bb78;
    color: white;
    box-shadow: 0 4px 15px rgba(72, 187, 120, 0.4);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(72, 187, 120, 0.6);
}

.btn-outline {
    background: transparent;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-outline:hover {
    background: #667eea;
    color: white;
}

/* Results section */
.session-info {
    background: #f7fafc;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid #667eea;
}

.session-info h3 {
    color: #2d3748;
    margin-bottom: 5px;
}

.session-info p {
    color: #718096;
    font-size: 0.9rem;
}

/* Pairs container */
.pairs-container {
    display: grid;
    gap: 15px;
    margin-bottom: 20px;
}

.pair-card {
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: all 0.3s ease;
}

.pair-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    border-color: #667eea;
}

.pair-info {
    display: flex;
    align-items: center;
    gap: 15px;
    flex: 1;
}

.person {
    background: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 500;
    color: #2d3748;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.pair-arrow {
    color: #667eea;
    font-size: 1.2rem;
}

/* Actions */
.actions {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

/* Sessions section */
.sessions-container {
    display: grid;
    gap: 20px;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
}

.session-card {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 20px;
    transition: all 0.3s ease;
    cursor: pointer;
}

.session-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
    border-color: #667eea;
}

.session-card h3 {
    color: #2d3748;
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.session-card p {
    color: #718096;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.session-names {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin-bottom: 15px;
}

.name-tag {
    background: #edf2f7;
    color: #4a5568;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 500;
}

.session-pairs {
    font-size: 0.9rem;
    color: #718096;
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: white;
    margin: 15% auto;
    padding: 30px;
    border-radius: 16px;
    width: 90%;
    max-width: 400px;
    text-align: center;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.success-icon {
    font-size: 3rem;
    color: #48bb78;
    margin-bottom: 20px;
}

/* Spinner */
.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

/* Responsive design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .input-section,
    .results-section,
    .sessions-section {
        padding: 20px;
    }
    
    .actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
}

/* Loading states */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* Error states */
.error {
    border-color: #e53e3e !important;
    background-color: #fed7d7 !important;
}

.error-message {
    color: #e53e3e;
    font-size: 0.9rem;
    margin-top: 5px;
}

/* Success states */
.success {
    border-color: #48bb78 !important;
    background-color: #f0fff4 !important;
}