:root {
    --color-primary: #1f2d72;
    --color-background: #ffffff;
    --color-accent: #8b77cc;

    --color-surface: #ffffff;
    --color-text-main: #1a1a1a;
    --color-text-muted: #4b5563;
    --color-border: #e5e7eb;

    --color-hover: rgba(139, 119, 204, 0.08);
    --color-primary-light: #2a3b8f;
    --color-primary-hover-bg: rgba(31, 45, 114, 0.05);
    --color-primary-alpha-10: rgba(31, 45, 114, 0.1);
    --color-primary-alpha-20: rgba(31, 45, 114, 0.2);
    --color-accent-alpha-10: rgba(139, 119, 204, 0.1);
    --color-accent-alpha-40: rgba(139, 119, 204, 0.4);
    --color-bg-soft: #f5f4fa;

    --color-success: #10b981;
    --color-success-bg: rgba(16, 185, 129, 0.1);
    --color-danger: #ef4444;
    --color-danger-bg: rgba(239, 68, 68, 0.1);

    --hover-surface: #182059;
    --hover-on-surface: #ffffff;

    --sidebar-width: clamp(240px, 20vw, 300px);
    --page-padding: clamp(1.5rem, 5vw, 4rem);
    --mobile-header-height: 3.25rem;
}

@media (max-width: 1024px) {
    :root {
        --page-padding: clamp(0.75rem, 3vw, 1.25rem);
        --mobile-header-height: 3.25rem;
    }
}

@media (max-width: 480px) {
    :root {
        --page-padding: 0.75rem;
        --mobile-header-height: 3rem;
    }
}

@media (max-width: 320px) {
    :root {
        --page-padding: 0.625rem;
        --mobile-header-height: 2.75rem;
    }
}

@media (max-width: 240px) {
    :root {
        --page-padding: 0.5rem;
        --mobile-header-height: 2.5rem;
    }
}

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

body {
    font-family:
        "Plus Jakarta Sans",
        system-ui,
        -apple-system,
        sans-serif;
    background-color: #ffffff;
    color: var(--color-text-main);
    line-height: 1.6;
    font-size: 15px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    text-decoration: none;
    color: inherit;
    transition:
        color 0.2s ease,
        background-color 0.2s ease;
}

button {
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    color: inherit;
}
*:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

.skip-link {
    position: absolute;
    left: 0.75rem;
    top: 0.75rem;
    z-index: 10000;
    padding: 0.625rem 1rem;
    background-color: var(--color-primary);
    color: #ffffff;
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: 0.375rem;
    text-decoration: none;
    transform: translateY(-200%);
    transition: transform 0.2s ease;
}

.skip-link:focus,
.skip-link:focus-visible {
    transform: translateY(0);
    outline: 2px solid #ffffff;
    outline-offset: 2px;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    color: var(--color-text-main);
    line-height: 1.2;
    letter-spacing: -0.02em;
    font-weight: 700;
}

h1 {
    font-size: 1.8rem;
}

h2 {
    font-size: 1.4rem;
}

h3 {
    font-size: 1.15rem;
}

h4 {
    font-size: 1.05rem;
}

h5 {
    font-size: 0.95rem;
}

h6 {
    font-size: 0.85rem;
}

p {
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

p:last-child {
    margin-bottom: 0;
}

small,
.text-small {
    font-size: 0.875rem;
}

.icon {
    width: clamp(16px, 1.5vw, 24px);
    height: clamp(16px, 1.5vw, 24px);
    flex-shrink: 0;
}

.icon-small {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.icon-large {
    width: clamp(20px, 2vw, 24px);
    height: clamp(20px, 2vw, 24px);
    flex-shrink: 0;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 1.5rem;
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: 0.5rem;
    transition: all 0.2s ease;
    text-decoration: none;
    cursor: pointer;
    border: 1px solid transparent;
}

.btn-primary {
    background-color: var(--color-primary);
    color: #ffffff;
    box-shadow: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--hover-surface);
    color: var(--hover-on-surface);
    border-color: var(--hover-surface);
    transform: translateY(-1px);
    box-shadow:
        0 4px 6px -1px rgba(15, 23, 42, 0.08),
        0 2px 4px -2px rgba(15, 23, 42, 0.04);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background-color: var(--color-surface);
    color: var(--color-text-main);
    border-color: var(--color-border);
    box-shadow: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
}

.btn-secondary:hover:not(:disabled) {
    background-color: var(--hover-surface);
    color: var(--hover-on-surface);
    border-color: var(--hover-surface);
}
:root {
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

.fade-in {
    animation: fadeIn var(--transition-normal) forwards;
}

.slide-up {
    opacity: 0;
    animation: slideUp var(--transition-slow) forwards;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hover-lift {
    transition:
        transform var(--transition-normal),
        box-shadow var(--transition-normal);
}

.hover-lift:hover {
    transform: translateY(-2px);
    box-shadow:
        0 10px 15px -3px rgba(15, 23, 42, 0.08),
        0 4px 6px -4px rgba(15, 23, 42, 0.04);
}

.action-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.btn-outline {
    padding: clamp(0.375rem, 1vw, 0.5rem) clamp(0.75rem, 2vw, 1rem);
    font-size: 0.85rem;
    border: 1px solid var(--color-border);
    border-radius: 0.375rem;
    color: var(--color-primary);
    background-color: transparent;
    transition: border-color var(--transition-fast);
}

.btn-outline:hover {
    background-color: var(--hover-surface);
    border-color: var(--hover-surface);
    color: var(--hover-on-surface);
}

/* Breadcrumbs — PN-style, RN theme */
.breadcrumbs {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.625rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    font-size: clamp(0.6875rem, 1.5vw, 0.75rem);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin-bottom: clamp(1rem, 2.5vw, 1.5rem);
}

.breadcrumb-home {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.25rem;
    background-color: var(--color-bg-soft);
    border: 1px solid transparent;
    color: var(--color-text-muted);
    transition:
        color var(--transition-fast),
        border-color var(--transition-fast);
}

.breadcrumb-home:hover {
    color: var(--color-primary);
    border-color: var(--color-border);
}

.breadcrumb-home svg {
    width: 0.875rem;
    height: 0.875rem;
}

.breadcrumb-separator {
    color: var(--color-border);
}

.breadcrumb-link {
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
}

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

.breadcrumb-segment {
    color: var(--color-text-muted);
}

.breadcrumb-current {
    color: #5b4b9a;
    font-weight: 700;
}

@media (max-width: 240px) {
    .breadcrumbs {
        gap: 0.375rem;
        font-size: 0.625rem;
    }

    .breadcrumb-home svg {
        width: 0.75rem;
        height: 0.75rem;
    }
}

/* Site-wide card & button hover: #182059 + white text (quiz page excluded) */
.subject-card:hover,
.home-page__card:hover,
.grid-card:hover,
.rn-q-related-card:hover,
.rn-q-testbank-card:hover,
.cb-option:hover,
.nclex-link-item:hover,
.stat-box:hover,
.btn-outline:hover,
.btn-primary:hover:not(:disabled),
.btn-secondary:hover:not(:disabled),
.btn-pill:hover,
.cb-btn-small:hover,
.nav-btn:hover,
.sub-nav-btn:hover,
.pillar-tab:hover,
.nclex-tab:hover,
.nclex-submit-btn:hover,
.accordion-header:hover,
.error-page__cta:hover {
    background-color: var(--hover-surface, #182059) !important;
    border-color: var(--hover-surface, #182059) !important;
    color: var(--hover-on-surface, #ffffff) !important;
}

.subject-card:hover .card-title,
.subject-card:hover .card-meta,
.subject-card:hover .card-number,
.subject-card:hover .book-icon,
.home-page__card:hover .home-page__card-title,
.home-page__card:hover .home-page__card-desc,
.home-page__card:hover .home-page__card-index,
.home-page__card:hover .home-page__card-arrow svg,
.grid-card:hover .card-label,
.grid-card:hover .card-value,
.rn-q-related-card:hover .rn-q-related-card__title,
.rn-q-related-card:hover .rn-q-related-card__meta,
.rn-q-testbank-card:hover,
.rn-q-testbank-card:hover .group-hover\:text-primary,
.rn-q-testbank-card:hover svg,
.rn-q-testbank-card:hover .text-primary,
.cb-option:hover,
.cb-option:hover .cb-option-label,
.cb-option:hover .cb-option-title,
.cb-option:hover .cb-option-desc,
.cb-option:hover .cb-option-meta,
.cb-option:hover .cb-option-content,
.cb-option:hover h4,
.cb-option:hover p,
.cb-option:hover span,
.cb-option:hover svg,
.nclex-link-item:hover,
.nclex-link-item:hover .icon,
.stat-box:hover .stat-value,
.stat-box:hover .stat-label,
.accordion-header:hover .accordion-title,
.accordion-header:hover .accordion-icon,
.nav-btn:hover .chevron-icon,
.pillar-tab:hover .pillar-tab-count,
.error-page__cta:hover .error-page__cta-icon {
    color: var(--hover-on-surface, #ffffff) !important;
}

.home-page__card:hover .home-page__card-index,
.home-page__card:hover .home-page__card-arrow {
    background-color: transparent !important;
    border-color: rgba(255, 255, 255, 0.35) !important;
}

.cb-option:hover .cb-checkbox {
    border-color: rgba(255, 255, 255, 0.55) !important;
    background-color: transparent !important;
    color: var(--hover-on-surface, #ffffff) !important;
}