html, body {
    height: 100%;
    margin: 0;
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: #F9F9F9;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
}

.chat-container {
    width: 100%;
    max-width: 800px;
    height: 90vh;
    max-height: 1000px;
    background: #FFFFFF;
    border-radius: 16px;
    border: 1px solid #E5E5E5;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.chat-header {
    padding: 16px 20px;
    background: #FFFFFF;
    color: #000000;
    font-weight: 600;
    text-align: center;
    border-bottom: 1px solid #F0F0F0;
    flex-shrink: 0;
}

.chat-body {
    flex-grow: 1;
    padding: 30px 20px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.chat-greeting {
    text-align: center;
    margin: auto 0;
    padding: 20px;
}

.chat-greeting h1 {
    font-weight: 700;
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.chat-greeting p {
    font-size: 1.1rem;
    color: #6c757d;
}

.chat-message {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    max-width: 100%;
    line-height: 1.6;
}

.chat-message .avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    font-weight: bold;
}

.message-content {
    padding-top: 8px;
    color: #333;
}

.message-user .avatar {
    background-color: #E0E0E0;
    color: #555;
}

.message-bot .avatar {
    background-color: #D0E6A5;
    color: #4A5C2F;
}

.chat-footer {
    padding: 20px;
    background-color: #fff;
    border-top: 1px solid #F0F0F0;
    flex-shrink: 0;
}

.chat-input-container {
    display: flex;
    align-items: center;
    border: 1px solid #E0E0E0;
    border-radius: 12px;
    padding: 8px 8px 8px 20px;
    transition: border-color .2s;
    background: #F9F9F9;
}

.chat-input-container:focus-within {
    border-color: #AAA;
    background: #fff;
}

.chat-footer .form-control {
    border: none;
    box-shadow: none;
    flex-grow: 1;
    padding: 10px 0;
    background: transparent;
}

.chat-footer .form-control:focus {
    box-shadow: none;
    border-color: transparent;
}

.chat-footer .btn {
    border-radius: 8px;
    width: 40px;
    height: 40px;
    flex-shrink: 0;
    background-color: #333;
    border-color: #333;
    display: flex;
    align-items: center;
    justify-content: center;
}
.chat-footer .btn:hover {
    background-color: #000;
    border-color: #000;
}