/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* IT-inspired color palette - dark, technical */
    --color-primary: #2563eb; /* Blue */
    --color-primary-dark: #1e40af;
    --color-secondary: #10b981; /* Green accent */
    --color-accent: #3b82f6;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-bg: #ffffff;
    --color-bg-light: #f9fafb;
    --color-bg-dark: #111827;
    --color-border: #e5e7eb;
    --color-success: #10b981;
    --color-error: #ef4444;
    
    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-heading: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    
    /* Container */
    --container-width: 1200px;
    --container-padding: 1.5rem;
}

body {
    font-family: var(--font-primary);
    color: var(--color-text);
    line-height: 1.6;
    background-color: var(--color-bg);
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* Navigation */
.navbar {
    background-color: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-menu a {
    text-decoration: none;
    color: var(--color-text);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: var(--color-primary);
}

.nav-menu .btn-nav {
    display: inline-block;
}

.btn-nav-mobile {
    display: none;
    position: absolute;
    right: var(--container-padding);
}

.btn-nav {
    background-color: #2DDDF7;
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: 0.5rem;
    transition: background-color 0.3s;
    text-decoration: none;
}

.btn-nav:hover {
    background-color: #25c4db;
    color: white;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
    position: absolute;
    left: var(--container-padding);
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--color-text);
    transition: all 0.3s;
}

.btn-nav-mobile {
    display: none;
}

/* Hero section */
.hero {
    padding: var(--spacing-xl) 0;
    background: linear-gradient(135deg, var(--color-bg-light) 0%, var(--color-bg) 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: center;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.hero-image img {
    width: 100%;
    max-width: 500px;
    height: auto;
    border-radius: 0.5rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background-color: var(--color-primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

/* Bestseller badge */
.bestseller {
    background-color: var(--color-bg-dark);
    color: white;
    padding: var(--spacing-sm) 0;
    text-align: center;
}

.bestseller-badge {
    font-weight: 600;
    font-size: 0.9rem;
    letter-spacing: 0.5px;
}

/* About book section */
.about-book {
    padding: var(--spacing-xl) 0;
}

.book-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    align-items: start;
}

.book-text h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.book-text p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-light);
    line-height: 1.8;
}

.book-image img {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: 0.5rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

/* CTA section */
.cta-section {
    background-color: var(--color-bg-light);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.cta-section h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.cta-section p {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
}

.newsletter-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.form-group input {
    flex: 1;
    padding: 1rem;
    border: 2px solid var(--color-border);
    border-radius: 0.5rem;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--color-primary);
}

.form-message {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: 0.5rem;
    display: none;
}

.form-message.success {
    background-color: #d1fae5;
    color: #065f46;
    display: block;
}

.form-message.error {
    background-color: #fee2e2;
    color: #991b1b;
    display: block;
}

.form-consents {
    margin-top: var(--spacing-md);
    text-align: left;
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    margin-bottom: var(--spacing-sm);
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--color-text-light);
    line-height: 1.5;
}

.checkbox-label input[type="checkbox"] {
    margin-top: 0.2rem;
    flex-shrink: 0;
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.checkbox-label .required {
    color: var(--color-error);
    font-weight: 600;
}

.form-privacy {
    margin-top: var(--spacing-sm);
    font-size: 0.85rem;
    color: var(--color-text-light);
    line-height: 1.6;
    text-align: justify;
}

.form-privacy a {
    color: var(--color-primary);
    text-decoration: underline;
}

.form-privacy a:hover {
    color: var(--color-primary-dark);
}

.newsletter-info {
    max-width: 600px;
    margin: var(--spacing-md) auto 0;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-border);
}

.newsletter-privacy {
    color: var(--color-text-light);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

.buycoffee-link {
    color: var(--color-text-light);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-top: var(--spacing-sm);
}

.buycoffee-link a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
}

.buycoffee-link a:hover {
    text-decoration: underline;
}

/* Table of contents */
.table-of-contents {
    padding: var(--spacing-xl) 0;
}

.table-of-contents h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
    text-align: center;
    color: var(--color-text);
}

.section-intro {
    text-align: center;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-lg);
    font-size: 1.1rem;
}

.toc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.toc-item {
    background-color: var(--color-bg-light);
    padding: var(--spacing-md);
    border-radius: 0.5rem;
    border: 1px solid var(--color-border);
}

.toc-item h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

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

.toc-item li {
    padding: 0.5rem 0;
    color: var(--color-text-light);
    border-bottom: 1px solid var(--color-border);
}

.toc-item li:last-child {
    border-bottom: none;
}

.toc-item li:before {
    content: "→ ";
    color: var(--color-primary);
    font-weight: bold;
}

/* Author section */
.author {
    background-color: var(--color-bg-light);
    padding: var(--spacing-xl) 0;
}

.author-content {
    max-width: 800px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: var(--spacing-lg);
    align-items: start;
}

.author-image {
    text-align: center;
}

.author-image img {
    width: 100%;
    max-width: 200px;
    height: auto;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.author h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.author p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-light);
    line-height: 1.8;
}

.author a {
    color: var(--color-primary);
    text-decoration: none;
}

.author a:hover {
    text-decoration: underline;
}

/* Order section */
.order {
    padding: var(--spacing-xl) 0;
}

.order h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-lg);
    text-align: center;
    color: var(--color-text);
}

.order-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    max-width: 1000px;
    margin: 0 auto;
}

.order-card {
    background-color: var(--color-bg-light);
    padding: var(--spacing-md);
    border-radius: 0.5rem;
    border: 2px solid var(--color-border);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.order-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.order-card.featured {
    border-color: var(--color-primary);
    background: linear-gradient(135deg, var(--color-bg-light) 0%, #eff6ff 100%);
}

.order-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.price {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.order-card ul {
    list-style: none;
    margin-bottom: var(--spacing-md);
    text-align: left;
}

.order-card li {
    padding: 0.5rem 0;
    color: var(--color-text-light);
}

.order-card li:before {
    content: "✓ ";
    color: var(--color-secondary);
    font-weight: bold;
}

/* Contact section */
.contact {
    background-color: var(--color-bg-light);
    padding: var(--spacing-lg) 0;
    text-align: center;
}

.contact h2 {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.contact a {
    color: var(--color-primary);
    text-decoration: none;
}

.contact a:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    background-color: var(--color-bg-dark);
    color: white;
    padding: var(--spacing-md) 0;
    text-align: center;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.footer-badges {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.rzetelna-badge {
    display: inline-block;
    transition: opacity 0.3s;
}

.rzetelna-badge:hover {
    opacity: 0.8;
}

.rzetelna-logo {
    height: 60px;
    width: auto;
    max-width: 200px;
}

.awards-logo {
    height: 60px;
    width: auto;
    max-width: 250px;
}

/* Responsive */
@media (max-width: 768px) {
    .navbar .container {
        gap: 1rem;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--color-bg);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-menu .btn-nav {
        display: none;
    }

    .btn-nav-mobile {
        display: inline-block;
        font-size: 0.875rem;
        padding: 0.5rem 1rem;
        white-space: nowrap;
        position: absolute;
        right: var(--container-padding);
    }

    .hero .container {
        grid-template-columns: 1fr;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .book-content {
        grid-template-columns: 1fr;
    }

    .form-group {
        flex-direction: column;
    }

    .toc-grid {
        grid-template-columns: 1fr;
    }

    .order-options {
        grid-template-columns: 1fr;
    }

    .author-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .author-image {
        margin-bottom: var(--spacing-md);
    }

    .author-image img {
        max-width: 150px;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .rzetelna-logo,
    .awards-logo {
        height: 50px;
        max-width: 180px;
    }
}

/* Floating Buttons Container */
.floating-buttons {
    position: fixed;
    left: 20px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    gap: 12px;
    z-index: 999;
}

/* Floating Blog Button */
.floating-blog {
    background: white;
    padding: 12px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transition: all 0.3s ease;
    border: 2px solid var(--color-border);
}

.floating-blog:hover {
    transform: scale(1.05);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.floating-blog-logo {
    width: 40px;
    height: 40px;
    object-fit: contain;
}

/* Floating Buy Me a Coffee Button */
.floating-buycoffee {
    background: white;
    color: #000;
    padding: 12px 16px;
    border-radius: 50px;
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transition: all 0.3s ease;
    border: 2px solid var(--color-border);
}

.floating-buycoffee:hover {
    transform: scale(1.05);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
    background: var(--color-bg-light);
}

.floating-buycoffee svg {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.floating-buycoffee span {
    white-space: nowrap;
}

@media (max-width: 768px) {
    .floating-buttons {
        left: 15px;
    }

    .floating-blog {
        padding: 10px;
    }

    .floating-blog-logo {
        width: 32px;
        height: 32px;
    }

    .floating-buycoffee {
        padding: 10px 14px;
        font-size: 0.85rem;
    }

    .floating-buycoffee svg {
        width: 20px;
        height: 20px;
    }

    .floating-buycoffee span {
        display: none;
    }
}

@media (max-width: 480px) {
    :root {
        --container-padding: 1rem;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .btn {
        width: 100%;
        text-align: center;
    }
}