:root {
    --op-bg: #f8fafc;
    --op-surface: #ffffff;
    --op-surface-subtle: #f1f5f9;
    --op-ink: #0f172a;
    --op-ink-muted: #475569;
    --op-accent: #e11d48;
    --op-accent-hover: #be123c;
    --op-accent-soft: #ffe4e6;
    --op-border: #e2e8f0;
    --op-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.04);
    --op-radius: 16px;
    --font-display: 'Montserrat', sans-serif;
    --font-body: 'Poppins', sans-serif;
    --container-max: 1180px;
}

/* Global Reset & Base Layout */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body.op-app-body {
    background-color: var(--op-bg);
    color: var(--op-ink);
    font-family: var(--font-body);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

main.op-main-shell {
    flex: 1;
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 2rem 1.5rem;
    position: relative;
}

/* Decorative Background SVG Pattern */
.op-bg-pattern {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100vw;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    color: var(--op-accent);
    overflow: hidden;
}

/* Header */
.op-header-bar {
    width: 100%;
    background-color: var(--op-ink);
    color: #ffffff;
    padding: 1.25rem 0;
    position: relative;
    z-index: 20;
}

.op-header-content {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.op-brand-anchor {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: #ffffff;
}

.op-brand-icon {
    width: 32px;
    height: 32px;
    color: var(--op-accent);
}

.op-brand-title {
    font-family: var(--font-display);
    font-weight: 800;
    font-size: 1.5rem;
    letter-spacing: -0.02em;
}

.op-header-deco {
    display: none;
    width: 200px;
    color: var(--op-accent);
}

@media (min-width: 768px) {
    .op-header-deco {
        display: block;
    }
}

/* Typography Headings */
.op-heading-primary {
    font-family: var(--font-display);
    font-weight: 800;
    font-size: 1.85rem;
    line-height: 1.25;
    color: var(--op-ink);
    text-transform: uppercase;
    margin-bottom: 1.25rem;
}

.op-heading-secondary {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--op-ink);
    text-transform: uppercase;
    text-align: center;
    margin-bottom: 2rem;
}

@media (min-width: 768px) {
    .op-heading-primary {
        font-size: 2.3rem;
    }
    .op-heading-secondary {
        font-size: 1.85rem;
    }
}

/* Preset A: Split Sticky Product Block */
.op-product-stage {
    position: relative;
    z-index: 10;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
    margin-bottom: 4rem;
    background-color: var(--op-surface);
    padding: 2rem;
    border-radius: var(--op-radius);
    box-shadow: var(--op-shadow);
    border: 1px solid var(--op-border);
}

@media (min-width: 900px) {
    .op-product-stage {
        flex-direction: row;
        align-items: flex-start;
        gap: 3.5rem;
        padding: 3rem;
    }

    .op-stage-left {
        width: 40%;
        position: sticky;
        top: 2rem;
        align-self: flex-start;
    }

    .op-stage-right {
        width: 60%;
    }
}

.op-picture-frame {
    display: block;
    width: 100%;
    background: radial-gradient(circle, var(--op-accent-soft) 0%, rgba(255,255,255,0) 70%);
    border-radius: var(--op-radius);
    padding: 1.5rem;
    text-align: center;
}

.op-product-img {
    max-width: 100%;
    height: auto;
    object-fit: contain;
    margin: 0 auto;
    filter: drop-shadow(0 15px 25px rgba(0,0,0,0.12));
}

.op-summary-card {
    background-color: var(--op-surface-subtle);
    padding: 1.25rem;
    border-radius: calc(var(--op-radius) - 4px);
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--op-accent);
}

.op-lead-copy {
    color: var(--op-ink-muted);
    font-size: 1rem;
    line-height: 1.6;
}

/* Features Stack inside Product Block */
.op-benefit-stack {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
    margin-bottom: 2rem;
}

.op-benefit-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--op-ink);
}

.op-check-ico {
    width: 20px;
    height: 20px;
    color: var(--op-accent);
    flex-shrink: 0;
}

/* Guarantee Badge (icon-left) */
.op-guarantee-strip {
    display: flex;
    align-items: center;
    gap: 1rem;
    background-color: var(--op-accent-soft);
    padding: 1rem 1.25rem;
    border-radius: calc(var(--op-radius) - 4px);
    margin-bottom: 2rem;
    border: 1px stroke rgba(225, 29, 72, 0.2);
}

.op-shield-ico {
    width: 32px;
    height: 32px;
    color: var(--op-accent);
    flex-shrink: 0;
}

.op-guarantee-text {
    display: flex;
    flex-direction: column;
    font-size: 0.875rem;
    color: var(--op-ink);
}

.op-guarantee-text strong {
    font-weight: 700;
    color: var(--op-accent-hover);
}

/* Price & CTA Panel */
.op-checkout-panel {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    align-items: stretch;
    background-color: var(--op-surface-subtle);
    padding: 1.5rem;
    border-radius: var(--op-radius);
    border: 1px solid var(--op-border);
}

@media (min-width: 550px) {
    .op-checkout-panel {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
    }
}

.op-price-badge {
    background-color: var(--op-accent);
    color: #ffffff;
    padding: 0.75rem 1.25rem;
    border-radius: calc(var(--op-radius) - 6px);
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    box-shadow: 0 4px 10px rgba(225, 29, 72, 0.25);
}

.op-price-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    opacity: 0.9;
}

.op-price-val {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 800;
}

.op-action-trigger {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    background-color: var(--op-accent);
    color: #ffffff;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.15rem;
    text-transform: uppercase;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: calc(var(--op-radius) - 4px);
    transition: background-color 0.2s ease, transform 0.1s ease;
    box-shadow: 0 4px 14px rgba(225, 29, 72, 0.35);
}

.op-action-trigger:hover {
    background-color: var(--op-accent-hover);
    transform: translateY(-2px);
}

.op-arrow-ico {
    width: 20px;
    height: 20px;
}

/* Features Section */
.op-highlights-area {
    position: relative;
    z-index: 10;
    margin-bottom: 4rem;
}

.op-highlight-stack {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.op-highlight-row {
    display: flex;
    align-items: flex-start;
    gap: 1.25rem;
    background-color: var(--op-surface);
    padding: 1.5rem;
    border-radius: var(--op-radius);
    box-shadow: var(--op-shadow);
    border: 1px solid var(--op-border);
}

.op-highlight-circle {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background-color: var(--op-accent-soft);
    color: var(--op-accent);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.op-feat-ico {
    width: 28px;
    height: 28px;
}

.op-highlight-body h3 {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--op-ink);
    margin-bottom: 0.25rem;
}

.op-highlight-body p {
    color: var(--op-ink-muted);
    font-size: 0.95rem;
}

/* Testimonials Section */
.op-feedback-zone {
    position: relative;
    z-index: 10;
    background-color: var(--op-surface-subtle);
    padding: 3rem 1.5rem;
    border-radius: var(--op-radius);
    margin-bottom: 2rem;
    border: 1px solid var(--op-border);
}

.op-feedback-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

@media (min-width: 640px) {
    .op-feedback-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.op-feedback-card {
    background-color: var(--op-surface);
    padding: 1.5rem;
    border-radius: var(--op-radius);
    border-top: 4px solid var(--op-accent);
    box-shadow: var(--op-shadow);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.op-card-top {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.op-user-avatar {
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background-color: var(--op-accent);
    color: #ffffff;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.op-user-info strong {
    display: block;
    font-size: 0.95rem;
    color: var(--op-ink);
}

.op-star-rating {
    color: #f59e0b;
    font-size: 0.85rem;
    letter-spacing: 2px;
}

.op-feedback-text {
    color: var(--op-ink-muted);
    font-size: 0.9rem;
    font-style: italic;
    line-height: 1.5;
}

/* Footer */
.op-footer-bar {
    width: 100%;
    background-color: var(--op-ink);
    color: #ffffff;
    padding: 2.5rem 0;
    margin-top: auto;
    position: relative;
    z-index: 20;
}

.op-footer-content {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    align-items: center;
    text-align: center;
}

@media (min-width: 768px) {
    .op-footer-content {
        flex-direction: row;
        justify-content: space-between;
        text-align: left;
    }
}

.op-footer-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.op-legal-links {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem 1.5rem;
    justify-content: center;
}

.op-legal-links a {
    color: #94a3b8;
    text-decoration: none;
    font-size: 0.875rem;
    transition: color 0.2s ease;
}

.op-legal-links a:hover {
    color: #ffffff;
}