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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

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

.chat-container {
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    height: calc(100vh - 40px);
    max-height: 800px;
}

.chat-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chat-header h1 {
    font-size: 24px;
    font-weight: 600;
}

.connection-status {
    display: flex;
    align-items: center;
    gap: 8px;
}

.status-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    display: inline-block;
}

.status-indicator.online {
    background-color: #4ade80;
    box-shadow: 0 0 8px #4ade80;
}

.status-indicator.offline {
    background-color: #ef4444;
}

.connection-panel {
    padding: 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
}

.connection-panel h2 {
    margin-bottom: 30px;
    color: #333;
}

.form-group {
    margin-bottom: 20px;
    width: 100%;
    max-width: 400px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
}

button {
    padding: 12px 24px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

button:active {
    transform: translateY(0);
}

#connectBtn {
    width: 100%;
    max-width: 400px;
}

.chat-main {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow: hidden;
}

.chat-info {
    padding: 15px 20px;
    background: #f9fafb;
    border-bottom: 1px solid #e5e7eb;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.btn-disconnect {
    padding: 8px 16px;
    background: #ef4444;
    font-size: 14px;
}

.btn-disconnect:hover {
    background: #dc2626;
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    background: #f9fafb;
}

.message {
    margin-bottom: 16px;
    padding: 12px 16px;
    border-radius: 12px;
    max-width: 70%;
    word-wrap: break-word;
}

.message.sent {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    margin-left: auto;
    text-align: right;
}

.message.received {
    background: white;
    color: #333;
    border: 1px solid #e5e7eb;
}

.message-header {
    font-size: 12px;
    opacity: 0.8;
    margin-bottom: 4px;
}

.message-text {
    font-size: 15px;
    line-height: 1.5;
}

.message-time {
    font-size: 11px;
    opacity: 0.7;
    margin-top: 4px;
}

.chat-input-panel {
    padding: 20px;
    background: white;
    border-top: 1px solid #e5e7eb;
}

.input-group {
    margin-bottom: 12px;
}

.input-group:last-child {
    margin-bottom: 0;
    display: flex;
    gap: 12px;
}

.input-group input {
    flex: 1;
    padding: 12px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 14px;
}

.input-group input:focus {
    outline: none;
    border-color: #667eea;
}

#sendBtn {
    padding: 12px 24px;
    white-space: nowrap;
}

.error-message {
    background: #fee2e2;
    color: #991b1b;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 16px;
    border: 1px solid #fecaca;
}

.success-message {
    background: #d1fae5;
    color: #065f46;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 16px;
    border: 1px solid #a7f3d0;
}

/* Scrollbar styling */
.chat-messages::-webkit-scrollbar {
    width: 8px;
}

.chat-messages::-webkit-scrollbar-track {
    background: #f1f1f1;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: #555;
}