:root {
    --primary: #5b21b6;
    --secondary: #ec4899;
    --background: #f8fafc;
    --surface: #ffffff;
    --text: #111827;
    --muted: #6b7280;
    --success: #10b981;
    --error: #ef4444;
    --shadow: 0 6px 24px rgba(0, 0, 0, 0.08);
    --glass: rgba(255, 255, 255, 0.85);
    --radius: 12px;
    --transition: 0.3s ease-in-out;
    --scrollbar-bg: #e2e8f0;
    --scrollbar-thumb: var(--primary);
}

[data-theme="dark"] {
    --primary: #7c3aed;
    --secondary: #f472b6;
    --background: #0f172a;
    --surface: #1e293b;
    --text: #f8fafc;
    --muted: #9ca3af;
    --shadow: 0 6px 24px rgba(0, 0, 0, 0.4);
    --glass: rgba(30, 41, 59, 0.9);
    --scrollbar-bg: #1e293b;
    --scrollbar-thumb: var(--primary);
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--background);
    color: var(--text);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color var(--transition), color var(--transition);
    overflow: hidden;
}

body::-webkit-scrollbar {
    width: 6px;
}

body::-webkit-scrollbar-track {
    background: var(--scrollbar-bg);
}

body::-webkit-scrollbar-thumb {
    background-color: var(--scrollbar-thumb);
    border-radius: 20px;
}

.chat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    font-size: 1.25rem;
    font-weight: 500;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 10;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
}

.status.online i {
    color: var(--success);
    font-size: 0.7rem;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

#clear-chat-btn {
    background: transparent;
    color: white;
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    cursor: pointer;
    transition: background var(--transition), transform var(--transition);
}

#clear-chat-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.1);
}

#clear-chat-btn:focus {
    outline: none;
    box-shadow: 0 0 8px rgba(255, 255, 255, 0.3);
}

.chat-container {
    display: flex;
    flex-direction: column;
    flex-grow: 1;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    backdrop-filter: blur(12px);
}

.chat-messages {
    flex-grow: 1;
    padding: 1.5rem;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    max-height: calc(100vh - 180px); /* Adjust for header and input */
    -webkit-overflow-scrolling: touch; /* Smooth scrolling on mobile */
}

.chat-messages::-webkit-scrollbar {
    width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
    background: var(--scrollbar-bg);
}

.chat-messages::-webkit-scrollbar-thumb {
    background-color: var(--scrollbar-thumb);
    border-radius: 20px;
}

.message {
    display: flex;
    flex-direction: column;
    max-width: 85%;
}

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

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

.message-content {
    padding: 1rem 1.2rem;
    border-radius: var(--radius);
    background-color: var(--glass);
    box-shadow: var(--shadow);
    position: relative;
    font-size: 0.95rem;
    line-height: 1.4;
}

.message.bot .message-content {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
}

.message.user .message-content {
    background: var(--background);
    color: var(--text);
    border: 1px solid rgba(var(--primary), 0.2);
}

.message-content::before {
    content: '';
    position: absolute;
    width: 0;
    height: 0;
    border-style: solid;
}

.message.bot .message-content::before {
    top: 12px;
    left: -8px;
    border-width: 8px 8px 8px 0;
    border-color: transparent var(--primary) transparent transparent;
}

.message.user .message-content::before {
    top: 12px;
    right: -8px;
    border-width: 8px 0 8px 8px;
    border-color: transparent transparent transparent var(--background);
}

.typing-indicator {
    display: flex;
    gap: 0.4rem;
    padding: 1rem;
}

.typing-indicator span {
    width: 10px;
    height: 10px;
    background-color: var(--muted);
    border-radius: 50%;
    animation: typing 1.2s infinite;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.3s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.6s;
}

@keyframes typing {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}

.chat-input {
    display: flex;
    padding: 1rem;
    background-color: var(--glass);
    gap: 0.75rem;
    border-top: 1px solid rgba(var(--muted), 0.2);
}

#user-input {
    flex-grow: 1;
    padding: 0.8rem 1.2rem;
    border: 1px solid var(--muted);
    border-radius: 8px;
    font-size: 1rem;
    background-color: var(--surface);
    color: var(--text);
    transition: border-color var(--transition), box-shadow var(--transition);
}

#user-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 8px rgba(var(--primary), 0.3);
    outline: none;
}

#send-btn {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.1rem;
    transition: transform var(--transition), box-shadow var(--transition);
}

#send-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(var(--primary), 0.3);
}

#send-btn:disabled {
    background: var(--muted);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.home-icon {
    background: transparent;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    transition: background var(--transition), transform var(--transition);
}

.home-icon:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.1);
}

@media (max-width: 768px) {
    .chat-container {
        margin: 10px;
    }

    .chat-messages {
        max-height: calc(100vh - 160px);
    }

    .chat-header {
        font-size: 1.1rem;
        padding: 0.8rem 1.2rem;
    }

    .chat-messages {
        padding: 1rem;
        gap: 1rem;
    }

    .message-content {
        padding: 0.8rem 1rem;
        font-size: 0.9rem;
    }

    #user-input {
        padding: 0.7rem 1rem;
        font-size: 0.95rem;
    }

    #send-btn {
        padding: 0.7rem 1.2rem;
        font-size: 1rem;
    }

    .home-icon, #clear-chat-btn {
        width: 36px;
        height: 36px;
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    .chat-container {
        margin: 5px;
    }

    .chat-messages {
        max-height: calc(100vh - 140px);
    }

    .chat-header {
        font-size: 1rem;
        padding: 0.7rem 1rem;
    }

    .message-content {
        padding: 0.7rem 0.9rem;
        font-size: 0.85rem;
    }

    #user-input {
        padding: 0.6rem 0.9rem;
        font-size: 0.9rem;
    }

    #send-btn {
        padding: 0.6rem 1rem;
        font-size: 0.95rem;
    }

    .home-icon, #clear-chat-btn {
        width: 32px;
        height: 32px;
        font-size: 1.1rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        transition: none !important;
        animation: none !important;
    }
}