* {
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    margin: 0;
    padding: 24px;
    display: grid;
    place-items: center;
    background: #eef1f5;
    font-family: Arial, sans-serif;
}

.chat-container {
    width: min(100%, 700px);
    height: 80vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
    border-radius: 14px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.chat-header {
    padding: 20px;
    background: #182433;
    color: white;
}

.chat-header h1,
.chat-header p {
    margin: 0;
}

.chat-header p {
    margin-top: 6px;
    color: #d4dce6;
}

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

.message {
    width: fit-content;
    max-width: 80%;
    margin-bottom: 12px;
    padding: 12px 16px;
    border-radius: 14px;
    line-height: 1.4;
}

.assistant-message {
    background: #e8edf3;
}

.user-message {
    margin-left: auto;
    background: #2764c5;
    color: white;
}

.chat-form {
    display: flex;
    gap: 10px;
    padding: 16px;
    border-top: 1px solid #dce1e7;
}

.chat-form input {
    flex: 1;
    min-width: 0;
    padding: 12px;
    border: 1px solid #b8c0ca;
    border-radius: 8px;
    font: inherit;
}

.chat-form button {
    padding: 12px 20px;
    border: 0;
    border-radius: 8px;
    background: #2764c5;
    color: white;
    font: inherit;
    cursor: pointer;
}

.chat-form button:hover {
    background: #1d4f9f;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
}