/* CSS Variables for theming and dark mode */
:root {
    --bg-color: #0f172a;
    --chat-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --user-msg: #3b82f6;
    --agent-msg: #334155;
    --border: #334155;
    --danger: #ef4444;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    overflow: hidden;
}

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

.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary);
    color: white;
    padding: 8px;
    z-index: 100;
    transition: top 0.2s;
}

.skip-link:focus {
    top: 0;
}

.chat-container {
    width: 100%;
    max-width: 600px;
    height: 90vh;
    background-color: var(--chat-bg);
    border-radius: 16px;
    display: flex;
    flex-direction: column;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.5);
    border: 1px solid var(--border);
    overflow: hidden;
}

.chat-header {
    padding: 16px 24px;
    background: rgba(30, 41, 59, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    z-index: 10;
}

.chat-header h1 {
    font-size: 1.1rem;
    font-weight: 600;
}

.chat-header .status {
    font-size: 0.8rem;
    color: #10b981;
    margin-top: 4px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.chat-header .status::before {
    content: '';
    display: block;
    width: 8px;
    height: 8px;
    background-color: #10b981;
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
    70% { box-shadow: 0 0 0 6px rgba(16, 185, 129, 0); }
    100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.chat-messages {
    flex: 1;
    padding: 24px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
    scrollbar-width: thin;
    scrollbar-color: var(--border) transparent;
}

.chat-messages::-webkit-scrollbar {
    width: 6px;
}
.chat-messages::-webkit-scrollbar-thumb {
    background-color: var(--border);
    border-radius: 3px;
}

.message {
    max-width: 80%;
    animation: slideIn 0.3s cubic-bezier(0.25, 0.8, 0.25, 1) forwards;
    opacity: 0;
    transform: translateY(10px);
    display: flex;
    flex-direction: column;
}

@keyframes slideIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message.user {
    align-self: flex-end;
}

.message.agent {
    align-self: flex-start;
}

.message-content {
    padding: 12px 16px;
    border-radius: 16px;
    line-height: 1.5;
    font-size: 0.95rem;
    word-break: break-word;
}

.message.user .message-content {
    background-color: var(--user-msg);
    color: white;
    border-bottom-right-radius: 4px;
}

.message.agent .message-content {
    background-color: var(--agent-msg);
    color: var(--text-main);
    border-bottom-left-radius: 4px;
}

.message audio {
    max-width: 100%;
    height: 40px;
    margin-top: 4px;
    border-radius: 20px;
}

.chat-input-area {
    padding: 16px 24px;
    background: var(--chat-bg);
    border-top: 1px solid var(--border);
}

.input-group {
    border: none;
    display: flex;
    gap: 12px;
    align-items: center;
}

#message-input {
    flex: 1;
    background-color: #0f172a;
    border: 1px solid var(--border);
    color: var(--text-main);
    padding: 12px 16px;
    border-radius: 24px;
    font-size: 0.95rem;
    transition: border-color 0.2s, box-shadow 0.2s;
    outline: none;
}

#message-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.icon-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background-color: var(--agent-msg);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.2s;
    outline: none;
}

.icon-btn:hover {
    background-color: #475569;
    transform: scale(1.05);
}

.icon-btn.primary {
    background-color: var(--primary);
    color: white;
}

.icon-btn.primary:hover {
    background-color: var(--primary-hover);
}

.icon-btn:focus-visible {
    box-shadow: 0 0 0 2px var(--text-main);
}

.icon-btn.recording {
    background-color: var(--danger);
    animation: pulse-danger 1.5s infinite;
}

@keyframes pulse-danger {
    0% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(239, 68, 68, 0); }
    100% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0); }
}

@media (max-width: 640px) {
    .chat-container {
        height: 100vh;
        max-width: 100%;
        border-radius: 0;
        border: none;
    }
}