:root {
    --bg-color: #0d1117;
    --panel-bg: rgba(22, 27, 34, 0.7);
    --border-color: rgba(48, 54, 61, 0.8);
    --text-main: #c9d1d9;
    --text-muted: #8b949e;
    --primary-gradient: linear-gradient(135deg, #2ea043 0%, #238636 100%);
    --primary-color: #2ea043;
    --user-msg-bg: linear-gradient(135deg, #1f6feb 0%, #164e63 100%);
    --bot-msg-bg: rgba(33, 38, 45, 0.8);
    --glass-blur: blur(16px);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    background-image: radial-gradient(circle at top right, rgba(46, 160, 67, 0.15), transparent 400px),
                      radial-gradient(circle at bottom left, rgba(31, 111, 235, 0.1), transparent 400px);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    padding: 20px;
    overflow: hidden;
}

.app-container {
    width: 100%;
    max-width: 900px;
    height: 90vh;
    background: var(--panel-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    overflow: hidden;
}

.chat-header {
    padding: 16px 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(13, 17, 23, 0.6);
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo {
    font-size: 28px;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    background-clip: text;
}

h1 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #f0f6fc;
}

.status-indicator {
    display: inline-block;
    width: 8px;
    height: 8px;
    background-color: #2ea043;
    border-radius: 50%;
    margin-right: 6px;
    box-shadow: 0 0 10px #2ea043;
}

.status-text {
    font-size: 0.75rem;
    color: var(--text-muted);
}

#clear-chat {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    transition: color 0.2s ease;
    padding: 8px;
    border-radius: 8px;
}

#clear-chat:hover {
    color: #f85149;
    background: rgba(248, 81, 73, 0.1);
}

.chat-container {
    flex: 1;
    padding: 24px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
    scroll-behavior: smooth;
}

.chat-container::-webkit-scrollbar {
    width: 6px;
}
.chat-container::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 10px;
}

.message {
    display: flex;
    gap: 16px;
    max-width: 85%;
    animation: fadeIn 0.3s ease forwards;
    opacity: 0;
    transform: translateY(10px);
}

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

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

.avatar {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 20px;
    flex-shrink: 0;
    background: rgba(255, 255, 255, 0.1);
}

.message.user .avatar {
    background: var(--user-msg-bg);
}

.message.system .avatar {
    background: var(--bot-msg-bg);
    border: 1px solid var(--border-color);
}

.message-content {
    padding: 14px 18px;
    border-radius: 18px;
    line-height: 1.6;
    font-size: 0.95rem;
    white-space: pre-wrap;
    word-break: break-word;
}

.message.user .message-content {
    background: var(--user-msg-bg);
    color: #fff;
    border-top-right-radius: 4px;
}

.message.system .message-content {
    background: var(--bot-msg-bg);
    border: 1px solid var(--border-color);
    border-top-left-radius: 4px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.chat-input-area {
    padding: 20px 24px;
    background: rgba(13, 17, 23, 0.8);
    border-top: 1px solid var(--border-color);
}

.input-form {
    display: flex;
    gap: 12px;
    align-items: flex-end;
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 8px 16px;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.input-form:focus-within {
    border-color: rgba(46, 160, 67, 0.5);
    box-shadow: 0 0 0 2px rgba(46, 160, 67, 0.1);
}

textarea {
    flex: 1;
    background: none;
    border: none;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    resize: none;
    max-height: 150px;
    padding: 10px 0;
    outline: none;
}

textarea::placeholder {
    color: var(--text-muted);
}

.send-btn {
    background: var(--primary-color);
    border: none;
    border-radius: 12px;
    width: 40px;
    height: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #fff;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    flex-shrink: 0;
    margin-bottom: 2px;
}

.send-btn:hover {
    background: #3fb950;
    transform: scale(1.05);
}

.send-btn:active {
    transform: scale(0.95);
}

.send-btn:disabled {
    background: var(--border-color);
    color: var(--text-muted);
    cursor: not-allowed;
    transform: none;
}

.footer-note {
    text-align: center;
    font-size: 0.7rem;
    color: var(--text-muted);
    margin-top: 12px;
}

.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 4px 8px;
    align-items: center;
}

.typing-dot {
    width: 6px;
    height: 6px;
    background: var(--text-muted);
    border-radius: 50%;
    animation: typing 1.4s infinite ease-in-out both;
}

.typing-dot:nth-child(1) { animation-delay: -0.32s; }
.typing-dot:nth-child(2) { animation-delay: -0.16s; }
.typing-dot:nth-child(3) { animation-delay: 0s; }

@keyframes typing {
    0%, 80%, 100% { transform: scale(0); }
    40% { transform: scale(1); }
}