body {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
}

h1, h2, h3, h4, h5, h6 {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
}

.main-title {
    text-align: center;
}

.main-description {
    text-align: center;
    font-size: 1.1em;
}

.sidebar-title {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
}

.expander-title {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
}

.thinking-time {
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    font-weight: bold;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

/* Apply fade-in animation to main content */
.main .block-container {
    animation: fadeIn 0.5s ease-out;
}

/* Apply slide-in animation to expanders */
.streamlit-expanderHeader {
    animation: slideIn 0.3s ease-out;
    transition: background-color 0.3s ease;
}

/* Smooth transition for expander content */
.streamlit-expanderContent {
    transition: max-height 0.3s ease-out, opacity 0.3s ease-out;
}

/* Pulse animation for thinking time */
.thinking-time {
    animation: pulse 2s infinite;
}

/* Hover effect for buttons */
.stButton > button {
    transition: all 0.3s ease;
}

.stButton > button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* Smooth transition for selectbox */
.stSelectbox {
    transition: all 0.3s ease;
}

/* Subtle hover effect for text input */
.stTextInput > div > div > input {
    transition: all 0.3s ease;
}

.stTextInput > div > div > input:hover {
    box-shadow: 0 0 0 1px rgba(49, 51, 63, 0.2);
}