@import url('https://fonts.googleapis.com/css2?family=Quicksand:wght@400;600;700&display=swap');

:root {
    --primary-blue-strong: #007bff;
    --accent-purple-strong: #8A2BE2;
    --background-light: #F0F8FF;
    --card-bg: #ffffff;
    --text-dark: #1e1e1e;
    --text-secondary: #34495e;
    --example-bg: #e6f0ff;
}

body { 
    font-family: 'Quicksand', sans-serif; 
    line-height: 1.6; 
    margin: 0; 
    padding: 0; 
    background-color: var(--background-light); 
    color: var(--text-dark); 
    display: flex;
    flex-direction: column;
    align-items: center;
    
}
       .back-to-home {
            display: block; 
            margin: 20px; 
            text-decoration: none; 
            color: var(--primary-blue-strong);
            font-weight: 600;
            transition: color 0.3s;
        }
        .back-to-home:hover {
            color: var(--accent-purple-strong);
        }
        .home-float-btn {
            position: fixed;
            top: 20px;
            right: 20px;
            width: 50px;
            height: 50px;
            background-color: var(--primary-blue-strong);
            color: var(--card-bg);
            border-radius: 50%;
            display: flex;
            justify-content: center;
            align-items: center;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.4);
            text-decoration: none;
            font-size: 24px;
            transition: background-color 0.3s, transform 0.2s;
            z-index: 5000;
        }

        .home-float-btn:hover {
            background-color: var(--accent-purple-strong);
            transform: scale(1.1);
        }

.header {
    background-color: var(--accent-purple-strong);
    color: #ffffff;
    width: 100%;
    padding: 50px 20px 30px 20px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.25);
    margin-bottom: 30px;
}

.header h1 {
    font-size: 2.8em;
    font-weight: 700;
    margin: 0;
    color: #ffffff;
}

.header p {
    font-size: 1.2em;
    font-weight: 400;
    margin-top: 5px;
    color: #f0f8ff;
}

.container { 
    max-width: 900px; 
    width: 95%;
    margin: 0 0 40px 0; 
    padding: 0; 
}

.topic-section {
    background: var(--card-bg); 
    padding: 30px; 
    border-radius: 12px; 
    box-shadow: 0 6px 15px rgba(0,0,0,0.15);
    margin-bottom: 25px;
    transition: all 0.3s ease-in-out;
    border-top: 5px solid var(--accent-purple-strong);
}

.topic-section:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.25);
}

.topic-title { 
    color: var(--primary-blue-strong);
    font-size: 2em;
    font-weight: 700;
    margin-bottom: 15px;
    position: relative;
    padding-bottom: 8px;
}

.topic-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 3px;
    background-color: var(--accent-purple-strong);
    border-radius: 2px;
}

.content-card p {
    font-size: 1.1em;
    color: var(--text-dark);
}

ul {
    list-style: none;
    padding-left: 0;
}

li { 
    margin-bottom: 10px; 
    padding-left: 25px;
    position: relative;
    font-size: 1em;
    color: var(--text-dark);
}

li::before {
    content: "•"; 
    position: absolute;
    left: 0;
    font-size: 1.5em;
    line-height: 0.8;
    color: var(--accent-purple-strong);
}

strong { 
    color: var(--primary-blue-strong);
    font-weight: 700;
}

.example { 
    background-color: var(--example-bg); 
    padding: 18px; 
    border-radius: 8px;
    border-left: 5px solid var(--primary-blue-strong);
    margin: 20px 0 0 0; 
    font-style: italic; 
    color: var(--text-secondary);
    font-weight: 400;
}

.footer {
    width: 100%;
    max-width: 900px;
    text-align: center;
    padding: 25px;
    border-top: 1px dashed var(--accent-purple-strong);
    margin-top: 20px;
    color: var(--text-secondary);
    font-size: 1em;
}

@media (max-width: 600px) {
    .header h1 {
        font-size: 2.2em;
    }
    .topic-title {
        font-size: 1.8em;
    }
}
button:focus {
    font-size: 17px;
    padding: 10px 25px;
    border-radius: 0.7rem;
    background-image: linear-gradient(rgb(214, 202, 254), rgb(158, 129, 254));
    border: 2px solid #0D47A1; 
    border-bottom: 5px solid #0D47A1;
    box-shadow: 0px 1px 6px 0px rgb(158, 129, 254);
    transform: translate(0, -3px);
    cursor: pointer;
    transition: 0.2s;
    transition-timing-function: linear;
}

button:active {
    transform: translate(0, 0);
    border-bottom: 2px solid #0D47A1;
}