:root {
    --ebook-bg: #f7f2eb;
    --ebook-card: #ffffff;
    --ebook-text: #2e2a26;
    --ebook-muted: #6b6259;
    --ebook-primary: #7b9680;
    --ebook-primary-hover: #68836d;
    --ebook-border: #e5dbcf;
    --ebook-shadow: 0 12px 30px rgba(46, 42, 38, 0.08);
    --ebook-radius: 16px;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: 'Open Sans', Arial, sans-serif;
    color: var(--ebook-text);
    background: radial-gradient(circle at top right, #fff9f3 0%, var(--ebook-bg) 45%, #efe5d9 100%);
    line-height: 1.6;
}

h1,
h2,
h3 {
    font-family: 'Merriweather', serif;
    line-height: 1.3;
    margin: 0 0 12px;
}

p {
    margin: 0 0 12px;
}

a {
    color: inherit;
}

.site-wrap {
    min-height: 100vh;
}

.topbar {
    border-bottom: 1px solid var(--ebook-border);
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(4px);
}

.topbar-inner {
    max-width: 1120px;
    margin: 0 auto;
    padding: 14px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.brand {
    text-decoration: none;
    font-family: 'Merriweather', serif;
    font-size: 1.05rem;
    font-weight: 700;
}

.nav-links {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.nav-links a {
    text-decoration: none;
    color: var(--ebook-muted);
    font-weight: 600;
}

.nav-links a:hover {
    color: var(--ebook-text);
}

.container {
    max-width: 1120px;
    margin: 0 auto;
    padding: 32px 20px 48px;
}

.hero {
    margin-bottom: 24px;
}

.hero h1 {
    font-size: clamp(1.75rem, 3vw, 2.5rem);
}

.hero p {
    color: var(--ebook-muted);
    max-width: 760px;
}

.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
}

.card {
    background: var(--ebook-card);
    border: 1px solid var(--ebook-border);
    border-radius: var(--ebook-radius);
    overflow: hidden;
    box-shadow: var(--ebook-shadow);
    display: flex;
    flex-direction: column;
}

.card-cover {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
    background: #e9ddd0;
}

.card-body {
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    height: 100%;
}

.card-title {
    margin: 0;
    font-size: 1.15rem;
}

.card-meta {
    color: var(--ebook-muted);
    font-size: 0.95rem;
}

.btn {
    display: inline-block;
    border: 0;
    border-radius: 999px;
    padding: 11px 18px;
    background: var(--ebook-primary);
    color: #fff;
    text-decoration: none;
    font-weight: 700;
    width: fit-content;
}

.btn:hover {
    background: var(--ebook-primary-hover);
}

.detail-grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 20px;
    align-items: start;
}

.detail-card,
.form-card {
    background: var(--ebook-card);
    border: 1px solid var(--ebook-border);
    border-radius: var(--ebook-radius);
    padding: 18px;
    box-shadow: var(--ebook-shadow);
}

.detail-card img {
    width: 100%;
    border-radius: 12px;
    margin-bottom: 14px;
}

.form-card h2 {
    margin-bottom: 8px;
}

.form-note {
    margin-top: 12px;
    color: var(--ebook-muted);
    font-size: 0.94rem;
}

.form-note a {
    color: inherit;
}

.footer {
    margin-top: 28px;
    color: var(--ebook-muted);
    font-size: 0.9rem;
}

@media (max-width: 860px) {
    .detail-grid {
        grid-template-columns: 1fr;
    }

    .topbar-inner {
        flex-direction: column;
        align-items: flex-start;
    }
}