:root {
    color-scheme: light;
    --chat-page-bg: #e9e1d7;
    --chat-bg: #f4efe8;
    --chat-surface: #ffffff;
    --chat-text: #172033;
    --chat-muted: #617084;
    --chat-border: #d8d2c8;
    --chat-accent: #128c7e;
    --chat-client: #d9fdd3;
    --chat-system: #ffffff;
    --chat-shadow: rgba(11, 20, 26, 0.08);
    --chat-error: #b42318;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100dvh;
    overflow: hidden;
    font-family: "Segoe UI", Arial, sans-serif;
    background: var(--chat-page-bg);
    color: var(--chat-text);
}

.chat-shell {
    height: 100dvh;
    min-height: 0;
    display: grid;
    grid-template-rows: auto minmax(0, 1fr) auto;
    width: min(100%, 760px);
    margin: 0 auto;
    background: var(--chat-surface);
    overflow: hidden;
}

.chat-header {
    padding: 10px 12px 9px;
    border-bottom: 1px solid var(--chat-border);
    background: var(--chat-surface);
}

.chat-status {
    margin: 0 0 3px;
    color: var(--chat-accent);
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
}

.chat-header h1 {
    margin: 0;
    font-size: 1.12rem;
    line-height: 1.25;
}

.chat-state-panel {
    align-self: center;
    margin: 24px;
    padding: 22px;
    border: 1px solid var(--chat-border);
    border-radius: 8px;
    background: var(--chat-surface);
    color: var(--chat-muted);
    line-height: 1.5;
}

.chat-form {
    display: grid;
    gap: 10px;
    margin-top: 16px;
}

.chat-label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--chat-text);
}

.chat-input {
    width: 100%;
    min-width: 0;
    min-height: 42px;
    padding: 10px 12px;
    border: 1px solid var(--chat-border);
    border-radius: 8px;
    color: var(--chat-text);
    font: inherit;
}

.chat-input:disabled {
    background: #edf1f6;
    color: var(--chat-muted);
}

.chat-button {
    min-height: 42px;
    padding: 10px 16px;
    border: 0;
    border-radius: 8px;
    background: var(--chat-accent);
    color: #ffffff;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
}

.chat-button:disabled {
    cursor: not-allowed;
    opacity: 0.65;
}

.chat-error {
    margin: 0;
    color: var(--chat-error);
    font-size: 0.92rem;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.chat-alert {
    margin: 8px 10px 0;
    padding: 12px 14px;
    border: 1px solid #f5c2c7;
    border-radius: 8px;
    background: #fff5f5;
    color: var(--chat-error);
}

.chat-transcript {
    min-height: 0;
    overflow-y: auto;
    overscroll-behavior: contain;
    padding: 8px 10px;
    background: var(--chat-bg);
}

.chat-empty {
    margin: 0;
    color: var(--chat-muted);
    text-align: center;
}

.chat-message {
    position: relative;
    max-width: 84%;
    margin: 0 0 6px;
    padding: 8px 10px;
    border-radius: 8px;
    box-shadow: 0 1px 1px var(--chat-shadow);
    line-height: 1.45;
    overflow-wrap: anywhere;
}

.chat-message p {
    margin: 0;
    white-space: pre-wrap;
}

.chat-message-label,
.chat-message-timestamp {
    display: block;
    color: var(--chat-muted);
    font-size: 0.72rem;
    line-height: 1.2;
}

.chat-message-label {
    margin-bottom: 3px;
    font-weight: 700;
}

.chat-message-timestamp {
    margin-top: 4px;
    text-align: right;
}

.chat-message.client .chat-message-label {
    text-align: right;
}

.chat-message.attachment {
    width: fit-content;
    min-width: min(100%, 210px);
}

.chat-message.client {
    margin-left: auto;
    background: var(--chat-client);
    color: var(--chat-text);
    border-top-right-radius: 2px;
}

.chat-message.system {
    margin-right: auto;
    background: var(--chat-system);
    color: var(--chat-text);
    border-top-left-radius: 2px;
}

.chat-message.operator {
    margin-right: auto;
    background: #fff7e6;
    color: var(--chat-text);
    border-top-left-radius: 2px;
}

.chat-message.client::after,
.chat-message.system::before,
.chat-message.operator::before {
    content: "";
    position: absolute;
    top: 0;
    width: 9px;
    height: 12px;
    background: inherit;
}

.chat-message.client::after {
    right: -6px;
    clip-path: polygon(0 0, 100% 0, 0 100%);
}

.chat-message.system::before,
.chat-message.operator::before {
    left: -6px;
    clip-path: polygon(0 0, 100% 0, 100% 100%);
}

.chat-message.streaming p::after {
    content: "";
    display: inline-block;
    width: 0.45em;
    height: 1em;
    margin-left: 2px;
    vertical-align: -0.15em;
    background: var(--chat-accent);
    animation: chat-caret 1s steps(2, start) infinite;
}

.chat-message.interrupted {
    border: 1px dashed var(--chat-error);
}

.chat-message.interrupted span {
    display: block;
    margin-top: 6px;
    color: var(--chat-error);
    font-size: 0.85rem;
}

.chat-attachment-message {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) auto;
    gap: 8px;
    align-items: center;
}

.chat-attachment-file-icon {
    position: relative;
    width: 18px;
    height: 22px;
    border: 2px solid currentColor;
    border-radius: 3px;
    opacity: 0.95;
}

.chat-attachment-file-icon::after {
    content: "";
    position: absolute;
    top: -2px;
    right: -2px;
    width: 7px;
    height: 7px;
    border-left: 2px solid currentColor;
    border-bottom: 2px solid currentColor;
    background: inherit;
}

.chat-attachment-file-name {
    min-width: 0;
    overflow-wrap: anywhere;
    font-weight: 600;
}

.chat-attachment-status-icon {
    display: inline-grid;
    place-items: center;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: rgba(17, 27, 33, 0.08);
    border: 2px solid currentColor;
    flex: 0 0 auto;
}

.chat-attachment-status-icon.pending::before {
    content: "";
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: currentColor;
    animation: chat-upload-pulse 1s ease-in-out infinite;
}

.chat-attachment-status-icon.uploaded {
    background: #0f9f6e;
    border-color: #0f9f6e;
    color: #ffffff;
}

.chat-attachment-status-icon.uploaded::before {
    content: "";
    width: 9px;
    height: 5px;
    border-left: 2px solid currentColor;
    border-bottom: 2px solid currentColor;
    transform: rotate(-45deg) translate(1px, -1px);
}

.chat-attachment-status-icon.failed {
    background: var(--chat-error);
    border-color: var(--chat-error);
    color: #ffffff;
    font-weight: 800;
}

.chat-attachment-status-icon.failed::before {
    content: "!";
    line-height: 1;
}

.chat-attachment-error {
    display: block;
    margin-top: 6px;
    color: var(--chat-error);
    font-size: 0.85rem;
}

.chat-composer {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 8px;
    padding: 8px;
    border-top: 1px solid var(--chat-border);
    background: var(--chat-surface);
}

.chat-attachment-form,
.chat-message-form {
    min-width: 0;
}

.chat-message-form {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 8px;
}

.chat-icon-button {
    width: 42px;
    height: 42px;
    border: 1px solid var(--chat-border);
    border-radius: 8px;
    background: var(--chat-surface);
    color: var(--chat-accent);
    font: inherit;
    font-size: 1.35rem;
    font-weight: 700;
    line-height: 1;
    cursor: pointer;
}

.chat-icon-button:disabled {
    cursor: not-allowed;
    opacity: 0.65;
}

.chat-composer .chat-error {
    grid-column: 1 / -1;
}

.chat-attachment-status {
    grid-column: 1 / -1;
    margin: 0;
    color: var(--chat-accent);
    font-size: 0.92rem;
}

@media (min-width: 800px) {
    body {
        padding: 5px;
    }

    .chat-shell {
        height: calc(100dvh - 10px);
        border: 1px solid var(--chat-border);
        border-radius: 8px;
        overflow: hidden;
    }

    .chat-header {
        padding: 14px 18px 12px;
    }

    .chat-header h1 {
        font-size: 1.25rem;
    }

    .chat-transcript {
        padding: 12px 16px;
    }

    .chat-composer {
        padding: 10px 12px;
    }
}

@keyframes chat-caret {
    50% {
        opacity: 0;
    }
}

@keyframes chat-upload-pulse {
    50% {
        opacity: 0.35;
    }
}