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

:root {
    --primary-color: #4285f4;
    --secondary-color: #34a853;
    --danger-color: #ea4335;
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-primary: #202124;
    --text-secondary: #5f6368;
    --border-color: #dadce0;
    --user-msg-bg: #4285f4;
    --assistant-msg-bg: #e8f0fe;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.5;
}

#app {
    height: 100vh;
    display: flex;
    flex-direction: column;
}

.screen {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.hidden {
    display: none !important;
}

/* Login Screen */
#login-screen {
    justify-content: center;
    align-items: center;
}

.login-container {
    background: var(--card-bg);
    padding: 3rem;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    text-align: center;
    max-width: 400px;
    width: 90%;
}

.login-container h1 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.subtitle {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.google-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    width: 100%;
    padding: 12px 24px;
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.google-btn:hover {
    background: var(--bg-color);
    border-color: var(--text-secondary);
}

.info-text {
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* Chat Screen */
.chat-header {
    background: var(--card-bg);
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-left h2 {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

.user-email {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.logout-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.875rem;
    transition: all 0.2s;
}

.logout-btn:hover {
    background: var(--bg-color);
}

.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 1.5rem;
}

.messages {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    display: flex;
    gap: 0.75rem;
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message.user {
    justify-content: flex-end;
}

.message-content {
    max-width: 70%;
    padding: 0.75rem 1rem;
    border-radius: 12px;
    word-wrap: break-word;
}

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

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

.message.system .message-content {
    background: #fff3cd;
    color: #856404;
    max-width: 100%;
    text-align: center;
    font-size: 0.875rem;
}

.message.error .message-content {
    background: #f8d7da;
    color: #721c24;
    max-width: 100%;
}

.message-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    flex-shrink: 0;
}

.message.assistant .message-avatar {
    background: var(--secondary-color);
}

.typing-indicator {
    display: flex;
    gap: 4px;
    padding: 1rem;
}

.typing-indicator span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-secondary);
    animation: typing 1.4s infinite;
}

.typing-indicator span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% {
        opacity: 0.3;
        transform: scale(0.8);
    }
    30% {
        opacity: 1;
        transform: scale(1);
    }
}

/* Input Area */
.input-container {
    background: var(--card-bg);
    border-top: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    display: flex;
    gap: 0.75rem;
    align-items: flex-end;
}

#message-input {
    flex: 1;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-family: inherit;
    font-size: 0.95rem;
    resize: none;
    max-height: 150px;
    overflow-y: auto;
}

#message-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.send-btn {
    padding: 0.75rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    width: 44px;
    height: 44px;
}

.send-btn:hover:not(:disabled) {
    background: #3367d6;
}

.send-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Responsive */
@media (max-width: 768px) {
    .message-content {
        max-width: 85%;
    }
    
    .login-container {
        padding: 2rem;
    }
    
    .chat-header {
        flex-direction: column;
        gap: 0.5rem;
        align-items: flex-start;
    }
}