:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --bg-tertiary: #1a1a1a;
    --text-primary: #ffffff;
    --text-secondary: #a1a1a1;
    --text-tertiary: #737373;
    --accent-primary: #ffc600;
    --border-primary: #262626;
    --gradient-text: linear-gradient(135deg, #ffffff 0%, #737373 100%);
    --radius-lg: 12px;
    --radius-md: 8px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'JetBrains Mono', monospace;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-primary);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: 'Geist Mono', monospace;
    font-size: 1.2rem;
    font-weight: 900;
    color: var(--text-primary);
    text-decoration: none;
    transition: color 0.2s ease;
    text-transform: uppercase;
}

.nav-logo:hover {
    color: var(--accent-primary);
}

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

.nav-link {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
}

.nav-link:hover {
    color: var(--accent-primary);
}

/* Container */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 80px 0;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 50%;
    left: -20%;
    transform: translateY(-50%);
    width: 100%;
    max-width: 1800px;
    height: 120%;
    background-image: url('dan_bg2.png');
    background-size: contain;
    background-position: center left;
    background-repeat: no-repeat;
    opacity: 0.08;
    pointer-events: none;
    z-index: 0;
}

@media (max-width: 968px) {
    .hero::before {
        display: none;
    }
}

.hero::after {
    content: '';
    position: absolute;
    top: 50%;
    right: -20%;
    transform: translateY(-50%);
    width: 100%;
    max-width: 1800px;
    height: 120%;
    background-image: url('dan_bg.png');
    background-size: contain;
    background-position: center right;
    background-repeat: no-repeat;
    opacity: 0.08;
    pointer-events: none;
    z-index: 0;
}

@media (max-width: 968px) {
    .hero::after {
        display: none;
    }
}

.hero .container {
    position: relative;
    z-index: 1;
}

.hero h1 {
    font-family: 'Geist Mono', monospace;
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 900;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
    line-height: 1.1;
    text-transform: uppercase;
    transition: color 0.3s ease;
    cursor: pointer;
}

.hero h1:hover {
    color: var(--accent-primary);
}

.hero .subtitle {
    font-size: clamp(1.25rem, 3vw, 1.5rem);
    font-weight: 400;
    margin-bottom: 3rem;
    color: var(--text-secondary);
}

.hero-content {
    display: flex;
    gap: 3rem;
    align-items: start;
    margin-top: 2rem;
}

.book-cover {
    flex-shrink: 0;
}

.book-cover img {
    width: 350px;
    height: auto;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-primary);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    transform: none;
    animation: none;
}

.book-meta {
    flex: 1;
    padding-top: 1rem;
}

.book-description {
    font-size: 1.1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.book-details {
    list-style: none;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
}

.book-details li {
    padding: 0.5rem 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-primary);
}

.book-details li:last-child {
    border-bottom: none;
}

/* Buttons */
.btn-primary, .btn-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 2rem;
    font-size: 0.9rem;
    font-weight: 600;
    font-family: 'JetBrains Mono', monospace;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 198, 0, 0.3);
}

.btn-cta {
    background-color: var(--accent-primary);
    color: var(--bg-primary);
    padding: 1rem 2.5rem;
    font-size: 1rem;
}

.btn-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 198, 0, 0.3);
}

/* Sections */
.section, .section-alt {
    padding: 6rem 0;
    border-top: 1px solid var(--border-primary);
}

.section-alt {
    background-color: var(--bg-secondary);
}

.section h2, .section-alt h2 {
    font-size: clamp(2rem, 4vw, 2.5rem);
    font-weight: 600;
    margin-bottom: 2rem;
    letter-spacing: -0.02em;
}

.section p, .section-alt p {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

/* Author Section */
.author-content {
    display: flex;
    gap: 3rem;
    align-items: center;
    margin-top: 2rem;
}

.author-image {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--border-primary);
    flex-shrink: 0;
}

.author-text {
    flex: 1;
}

/* Blockquote */
blockquote {
    margin: 3rem 0;
    padding: 2rem;
    background-color: var(--bg-secondary);
    border-left: 4px solid var(--accent-primary);
    border-radius: var(--radius-md);
    font-size: 1.1rem;
    line-height: 1.7;
    font-style: italic;
    color: var(--text-primary);
}

/* Handwritten Endorsement Section */
.endorsement-section {
    padding: 6rem 0;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-primary);
    border-bottom: 1px solid var(--border-primary);
    overflow: hidden;
}

.endorsement-section .container {
    max-width: 100%;
    padding: 0 4rem;
}

.handwritten-quote {
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 3rem;
    transform: rotate(-1.5deg);
    position: relative;
}

.handwritten-quote p {
    font-family: 'Caveat', cursive;
    font-size: clamp(2rem, 4vw, 3rem);
    line-height: 1.4;
    color: var(--text-primary);
    margin: 0;
    font-weight: 600;
    text-align: center;
    letter-spacing: 0.02em;
}

.signature {
    display: block;
    font-family: 'Caveat', cursive;
    font-size: clamp(1.5rem, 3vw, 2rem);
    color: var(--accent-primary);
    margin-top: 2rem;
    text-align: right;
    font-weight: 700;
    transform: rotate(-2deg);
}

/* CTA Section */
.section-cta {
    padding: 6rem 0;
    text-align: center;
    background-color: var(--bg-primary);
    border-top: 1px solid var(--border-primary);
}

.section-cta h2 {
    font-size: clamp(2.5rem, 5vw, 3rem);
    font-weight: 600;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

.section-cta p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: var(--bg-secondary);
    margin: 10% auto;
    padding: 2.5rem;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 500px;
    position: relative;
    box-shadow: 0 25px 70px rgba(0, 0, 0, 0.8);
}

.close {
    color: var(--text-secondary);
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    line-height: 1;
    transition: color 0.2s ease;
}

.close:hover {
    color: var(--accent-primary);
}

.modal h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 1.5rem;
    font-weight: 600;
}

.modal p {
    margin-bottom: 2rem;
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

#newsletter-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

#newsletter-form input {
    padding: 1rem;
    border: 1px solid var(--border-primary);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: 'JetBrains Mono', monospace;
    border-radius: var(--radius-md);
    transition: all 0.2s ease;
}

#newsletter-form input:focus {
    outline: none;
    border-color: var(--accent-primary);
    background: var(--bg-primary);
}

#newsletter-form input::placeholder {
    color: var(--text-tertiary);
}

#newsletter-form button {
    padding: 1rem;
    background: var(--accent-primary);
    color: var(--bg-primary);
    border: none;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    letter-spacing: 0.5px;
    font-family: 'JetBrains Mono', monospace;
    text-transform: uppercase;
    border-radius: var(--radius-md);
    transition: all 0.3s ease;
}

#newsletter-form button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 198, 0, 0.3);
}

/* Footer */
footer {
    background: var(--bg-secondary);
    padding: 3rem 0;
    text-align: center;
    border-top: 1px solid var(--border-primary);
}

footer p {
    color: var(--text-tertiary);
    font-size: 0.85rem;
}

/* Selection */
::selection {
    background-color: var(--accent-primary);
    color: var(--bg-primary);
}

::-moz-selection {
    background-color: var(--accent-primary);
    color: var(--bg-primary);
}

/* Scrollbar */
* {
    scrollbar-width: thin;
    scrollbar-color: transparent transparent;
}

*:hover {
    scrollbar-color: var(--border-primary) var(--bg-primary);
}

::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: transparent;
    border-radius: 5px;
    transition: background 0.3s ease;
}

body:hover::-webkit-scrollbar-thumb {
    background: var(--border-primary);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero .container {
    animation: none;
}

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

    .nav-menu {
        gap: 1rem;
        font-size: 0.85rem;
    }

    .container {
        padding: 0 1.5rem;
    }

    .hero .container {
        padding: 0 1.5rem;
    }

    .hero {
        padding: 100px 0 60px;
    }

    .hero h1, .hero .subtitle {
        width: calc(100vw - 3rem);
        max-width: 350px;
        margin-left: auto;
        margin-right: auto;
        text-align: left;
    }

    .hero-content {
        flex-direction: column;
        gap: 2rem;
        padding: 0;
        align-items: center;
    }

    .book-cover {
        width: 100%;
        display: flex;
        justify-content: center;
        padding: 0;
        margin: 0;
    }

    .book-cover img {
        width: calc(100vw - 3rem);
        max-width: 350px;
    }

    .book-meta {
        width: calc(100vw - 3rem);
        max-width: 350px;
    }

    .section, .section-alt, .section-cta {
        padding: 4rem 0;
    }

    blockquote {
        padding: 1.5rem;
        font-size: 1rem;
    }

    .author-content {
        flex-direction: column;
        text-align: center;
        gap: 2rem;
    }

    .author-image {
        margin: 0 auto;
    }

    .endorsement-section {
        padding: 4rem 0;
    }

    .endorsement-section .container {
        padding: 0 1rem;
    }

    .handwritten-quote {
        padding: 1.5rem;
        transform: rotate(-0.5deg);
        max-width: 100%;
    }

    .handwritten-quote p {
        font-size: 1.8rem;
    }

    .signature {
        font-size: 1.3rem;
    }
}

@media (max-width: 480px) {
    .nav-menu {
        gap: 0.75rem;
    }

    .nav-link {
        font-size: 0.8rem;
    }

    .hero {
        padding: 80px 0 40px;
    }

    .modal-content {
        margin: 20% auto;
        padding: 2rem;
    }
}

/* Form Messages */
.form-message {
    margin: 1rem 0;
    padding: 1rem;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 500;
    text-align: center;
    animation: fadeIn 0.3s ease-out;
}

.form-message.success {
    background-color: rgba(40, 200, 64, 0.1);
    color: #28c840;
    border: 1px solid rgba(40, 200, 64, 0.3);
}

.form-message.error {
    background-color: rgba(255, 95, 87, 0.1);
    color: #ff5f57;
    border: 1px solid rgba(255, 95, 87, 0.3);
}

.form-message.info {
    background-color: rgba(255, 198, 0, 0.1);
    color: var(--accent-primary);
    border: 1px solid rgba(255, 198, 0, 0.3);
}