:root {
    --page-bg: #f3f4f6;
    --panel-bg: #ffffff;
    --title-color: #1f2937;
    --input-bg: #f9fafb;
    --border-color: #d1d5db;
    --border-color-focus: #464747;
    --border-radius: 16px;
    --button-bg: #464747;
    --button-text: #ffffff;
    --message-bg: #eef2ff;
    --message-text: #1f2937;
    
}

body {
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    background: var(--page-bg);
    font-family: Seoge UI, Helvetica, Arial, sans-serif;
    overflow: hidden;
}

header h1 {
    color: var(--title-color);
}

main {
    width: calc(100vw - 2rem);
    background: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    display: flex;
    flex-direction: column;
    flex-grow: 1;
    overflow: hidden;
    text-align: center;
    justify-content: center;
}

#messages {
    flex-grow: 1;
    padding: 1rem;
    overflow-y: auto;
    overflow-x: hidden;
}

.message {
    width: max-content;
    max-width: 80%;
    padding: 0.25rem 1rem;
    border-radius: var(--border-radius) var(--border-radius) var(--border-radius) 0;
    background: var(--message-bg);
    border: 1px solid var(--border-color);
    margin-bottom: 0.25rem;
}

.message p {
    margin: 0;
    color: var(--message-text);
    line-height: 1.5;
    overflow-wrap: break-word;
}

.message.myself {
    text-align: right;
    align-self: end;
    float: right;
    clear: both;
    border-radius: var(--border-radius) var(--border-radius) 0 var(--border-radius);
}

#form {
    display: flex;
    gap: 1rem;
    align-items: center;
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

#input {
    margin: 0;
    padding: 0 1rem;
    flex: 1;
    height: calc(var(--border-radius) * 2);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: var(--input-bg);
    font-size: 1rem;
    outline: none;
}

#input:focus {
    border-color: var(--border-color-focus);
}

#sendButton {
    height: calc(var(--border-radius) * 2);
    padding: 1rem;
    border: none;
    border-radius: var(--border-radius);
    background: var(--button-bg);
    color: var(--button-text);
    font-weight: 700;
    cursor: pointer;
    display: flex;
    align-items: center;
}

footer {
    padding: 1rem;
    text-align: center;
    color: var(--message-text);
}