:root {
    --primary-color: #5d6d84; /* Soft Blue-Grey (for headings/accents) */
    --secondary-color: #f7f7f7; /* Near-White background */
    --text-color: #333333; /* Main text color */
    --subtle-text-color: #6c757d; /* Lighter text for context */
    --accent-color: #2ecc71; /* Green (for CTAs/buttons) */
    --border-radius: 8px;
    --transition-speed: 0.3s;
}

/* ----------------------------------- */
/* 1. Base Reset and Typography Setup  */
/* ----------------------------------- */

/* Box model reset for predictability */
*, *::before, *::after {
    box-sizing: border-box;
}

/* Base Body Styles */
body {
    font-family: 'Inter', sans-serif; /* Assumes Inter is linked in HTML */
    line-height: 1.6;
    color: var(--text-color);
    background-color: #ffffff; /* Default background */
    padding: 1rem;
}

/* Headings (H1 - H6) */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Inter', sans-serif;
    color: var(--primary-color);
    margin: 1.5rem 0 0.5rem 0; /* Consistent vertical rhythm */
    line-height: 1.2;
}

h1 { font-size: 2.5rem; font-weight: 700; }
h2 { font-size: 2rem; font-weight: 600; border-bottom: 1px solid #e0e0e0; padding-bottom: 0.5rem; }
h3 { font-size: 1.5rem; font-weight: 600; }
h4 { font-size: 1.25rem; font-weight: 500; }

/* Paragraphs */
p {
    margin-bottom: 1rem;
    font-size: 1rem;
}

/* ----------------------------------- */
/* 2. Links and Lists                  */
/* ----------------------------------- */

/* Standard Links */
a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-speed), border-color var(--transition-speed);
}

a:hover {
    color: var(--accent-color);
    text-decoration: underline;
}

/* If chapter is available make the read online in the toc green */
.toc .available .status-indicator {
    color: #28a745; /* Green for "Go/Available" */
    font-size: 0.9em;
    font-weight: normal;
}

/* Lists */
ul, ol {
    margin: 0 0 1rem 1.5rem;
    padding: 0;
}

li {
    margin-bottom: 0.5rem;
}

/* ----------------------------------- */
/* 3. Buttons and Interactive Elements */
/* ----------------------------------- */

button, .button-style {
    display: inline-block;
    background-color: var(--accent-color);
    color: white;
    padding: 0.6rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    text-decoration: none; /* For elements using button styles */
    transition: background-color var(--transition-speed), transform 0.1s;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

button:hover, .button-style:hover {
    background-color: #27ae60;
    transform: translateY(-1px);
}

/* ----------------------------------- */
/* 4. Forms and Inputs                 */
/* ----------------------------------- */

input[type="text"],
input[type="email"],
input[type="password"],
textarea,
select {
    width: 100%;
    padding: 0.75rem 1rem;
    margin-bottom: 1rem;
    border: 1px solid #ced4da;
    border-radius: var(--border-radius);
    font-size: 1rem;
    color: var(--text-color);
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

input:focus,
textarea:focus,
select:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(93, 109, 132, 0.2); /* Subtle focus ring */
}

label {
    display: block;
    margin-bottom: 0.25rem;
    font-weight: 500;
    color: var(--subtle-text-color);
    text-align: left;
}

/*-----------------------------*/
/* Call to Action Button        */
/*------------------------------*/

/* * 5. CALL TO ACTION (CTA) BUTTON 
         */
.cta-button {
        display: inline-block;
        background-color: var(--accent-color);
        color: white;
        padding: 0.75rem 2rem;
        text-decoration: none;
        border-radius: 50px;
        font-weight: 600;
        border: none;
        cursor: pointer;
        transition: background-color 0.3s, transform 0.2s, box-shadow 0.3s;
        box-shadow: 0 4px 15px rgba(46, 204, 113, 0.4);
}

.cta-button:hover {
       background-color: #27ae60; /* Slightly darker green */
       transform: translateY(-2px); /* Subtle lift effect */
       box-shadow: 0 6px 20px rgba(46, 204, 113, 0.6);
}

/* ----------------------------------- */
/* 6. Images and Media                 */
/* ----------------------------------- */

img {
    max-width: 50%; /* Image scales down if container is smaller than its original width */
    height: auto;    /* Crucial: Maintains aspect ratio when scaling down */
    display: block;  /* Treats the image as a block element */
    border-radius: var(--border-radius); /* Inherit soft corners from theme */
    margin: 1rem auto; /* Centers the image if it's smaller than the container and adds vertical spacing */
}