/* BookAdvisor — white business theme */
:root {
    --bg-page: #F5F7FA;
    --bg-surface: #FFFFFF;
    --color-primary: #1A365D;
    --color-accent: #2B6CB0;
    --color-text: #1A202C;
    --color-muted: #718096;
    --color-border: #E2E8F0;
    --footer-bg: #EDF2F7;
    --radius: 6px;
    --shadow-sm: 0 1px 3px rgba(26, 54, 93, 0.06);
    --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
}

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

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Navbar — white business */
.navbar {
    background: var(--bg-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: none;
    position: relative;
    z-index: 100;
}

.navbar-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
    flex-wrap: wrap;
    position: relative;
}

.navbar-brand {
    color: var(--color-primary);
    text-decoration: none;
    font-size: 1.5em;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
    letter-spacing: -0.02em;
}

.navbar-nav {
    display: flex;
    list-style: none;
    gap: 8px;
    align-items: center;
}

.nav-item {
    position: relative;
}

.nav-link {
    color: var(--color-text);
    text-decoration: none;
    font-weight: 500;
    padding: 8px 14px;
    border-radius: var(--radius);
    transition: color 0.2s ease, background 0.2s ease;
    display: flex;
    align-items: center;
    gap: 6px;
}

.nav-link:hover {
    color: var(--color-primary);
    background: var(--bg-page);
    transform: none;
}

.nav-link.active {
    color: var(--color-primary);
    background: transparent;
    box-shadow: inset 0 -2px 0 var(--color-primary);
    border-radius: 0;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--color-primary);
    font-size: 1.5em;
    cursor: pointer;
    padding: 8px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 600;
    font-size: 1em;
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
    border: 1px solid transparent;
    cursor: pointer;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background: #142844;
    color: #fff;
    transform: none;
    box-shadow: none;
}

.btn-secondary {
    background: transparent;
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
}

.btn-secondary:hover {
    background: var(--color-primary);
    color: #fff;
    transform: none;
}

/* Page headers / hero — light surfaces */
.hero,
.page-header,
.header {
    background: var(--bg-surface) !important;
    color: var(--color-text) !important;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    text-shadow: none !important;
}

.hero h1,
.page-header h1,
.header h1,
.header .book-title {
    color: var(--color-primary) !important;
    text-shadow: none !important;
}

.hero p,
.page-header p,
.header p,
.header .book-subtitle {
    color: var(--color-muted) !important;
    opacity: 1 !important;
}

/* Cards / panels */
.feature-card,
.search-section,
.stats-bar,
.book-card,
.sidebar,
.book-info,
.description,
.status-card,
.mcp-info-card,
.quick-start {
    background: var(--bg-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
}

.feature-card:hover,
.book-card:hover,
.status-card:hover,
.mcp-info-card:hover {
    transform: none;
    box-shadow: 0 2px 8px rgba(26, 54, 93, 0.08);
    border-color: #CBD5E0;
}

/* Section titles */
.section-title,
.feature-title,
.step-title,
.book-title {
    color: var(--color-primary);
}

.section-subtitle,
.feature-description,
.step-description,
.stats-info {
    color: var(--color-muted);
}

/* Accent buttons used across list/search/upload */
.search-btn,
.upload-btn,
.pagination-btn.current {
    background: var(--color-primary) !important;
    color: #fff !important;
    border: none;
    border-radius: var(--radius);
    box-shadow: none;
}

.search-btn:hover,
.upload-btn:hover {
    background: #142844 !important;
    transform: none !important;
    box-shadow: none !important;
    color: #fff !important;
}

.search-input:focus,
.format-select:focus {
    outline: none;
    border-color: var(--color-accent) !important;
    box-shadow: 0 0 0 3px rgba(43, 108, 176, 0.12) !important;
}

.file-input-display:hover,
.file-input-display.dragover {
    border-color: var(--color-accent) !important;
    background: #EBF4FF !important;
}

.file-icon {
    color: var(--color-primary) !important;
}

.progress-fill {
    background: var(--color-primary) !important;
}

/* Breadcrumb */
.breadcrumb a {
    color: var(--color-accent);
}

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

/* Stats band on landing (if present) */
.stats {
    background: var(--bg-surface) !important;
    color: var(--color-text) !important;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
}

.stat-number {
    color: var(--color-primary);
}

.stat-label {
    color: var(--color-muted);
    opacity: 1 !important;
}

.step-number {
    background: var(--color-primary) !important;
    color: #fff !important;
}

/* Status / lab accents */
.status-value,
.status-card::before,
.mcp-info-card::before {
    color: var(--color-primary);
}

.status-card::before,
.mcp-info-card::before {
    background: var(--color-primary) !important;
}

/* Footer — light */
.footer {
    background: var(--footer-bg) !important;
    color: var(--color-muted) !important;
    text-align: center;
    padding: 32px 0;
    margin-top: 48px;
    border-top: 1px solid var(--color-border);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.footer p {
    margin: 0;
    font-size: 0.95em;
    color: var(--color-muted);
}

/* Mobile nav */
@media (max-width: 768px) {
    .navbar-container {
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
        height: 70px;
        padding: 0 20px;
    }

    .navbar-nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-surface);
        flex-direction: column;
        padding: 12px 16px 20px;
        box-shadow: 0 8px 16px rgba(26, 54, 93, 0.08);
        border-bottom: 1px solid var(--color-border);
        z-index: 1000;
        gap: 4px;
    }

    .navbar-nav.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
    }

    .nav-link.active {
        box-shadow: none;
        background: var(--bg-page);
        border-radius: var(--radius);
    }
}