:root {
    /* Purple Wisdom Theme - Light Mode */
    --color-primary: #6B46C1;
    --color-primary-light: #8B5CF6;
    --color-primary-dark: #553C9A;
    --color-primary-container: #EDE9FE;
    --color-secondary: #A78BFA;
    --color-tertiary: #14B8A6;
    --color-success: #059669;
    --color-bg: #FAFAFA;
    --color-surface: #FFFFFF;
    --color-surface-variant: #F3F4F6;
    --color-text: #111827;
    --color-text-secondary: #1F2937;
    --color-text-muted: #6B7280;
    --color-border: #E5E7EB;
    --color-border-light: #D1D5DB;
    
    --font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2.5rem;
    --spacing-xl: 4rem;
    --spacing-2xl: 6rem;
    --max-width: 100%;
    --content-width: 540px;
    --padding-x: 1.5rem;
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--padding-x);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.container > * {
    max-width: var(--content-width);
    width: 100%;
    text-align: center;
}

.container > .play-button {
    width: auto;
}

/* Hero Section */
.hero {
    padding: var(--spacing-xl) 0;
    min-height: 90vh;
    display: flex;
    align-items: center;
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: 600;
    font-size: 1.25rem;
    color: var(--color-text);
    margin-bottom: var(--spacing-lg);
}

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    object-fit: cover;
}

h1 {
    font-size: 2rem;
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.subtitle {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    line-height: 1.6;
    margin-bottom: var(--spacing-lg);
}

.play-button {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    background-color: var(--color-primary);
    color: #fff;
    padding: 0.875rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    transition: background-color 0.2s ease, transform 0.15s ease, box-shadow 0.2s ease;
}

.play-button:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-1px);
}

.play-button:active {
    transform: translateY(0);
}

.play-button svg {
    flex-shrink: 0;
}

.play-button-text {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
    text-align: left;
}

.play-button-small {
    font-size: 0.625rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    opacity: 0.9;
}

.play-button-large {
    font-size: 1.125rem;
    font-weight: 500;
}

.trust-copy {
    margin-top: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--color-text-muted);
    letter-spacing: 0.01em;
}

/* Problem Section */
.problem {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-surface);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.problem h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.problem p {
    font-size: 1.0625rem;
    color: var(--color-text-muted);
    line-height: 1.8;
}

/* How It Works Section */
.how-it-works {
    padding: var(--spacing-xl) 0;
}

.how-it-works h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text);
}

.steps {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    max-width: var(--content-width);
}

.steps li {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    text-align: left;
}

.step-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    background-color: var(--color-primary-container);
    border: 1px solid var(--color-secondary);
    border-radius: 50%;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-primary);
    flex-shrink: 0;
}

.step-content {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    padding-top: 0.25rem;
}

.step-content strong {
    font-weight: 600;
    color: var(--color-text);
}

.step-content span {
    font-size: 0.9375rem;
    color: var(--color-text-muted);
}

/* Section Nudge */
.section-nudge {
    margin-top: var(--spacing-lg);
    font-size: 1rem;
    font-style: italic;
    color: var(--color-text-muted);
}

/* Why CardFinder Section */
.why {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-surface);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.why h2 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text);
}

.benefits {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    max-width: var(--content-width);
}

.benefits li {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1rem;
    color: var(--color-text);
    text-align: left;
}

.benefits svg {
    color: var(--color-success);
    flex-shrink: 0;
}

/* Final CTA Section */
.final-cta {
    padding: var(--spacing-xl) 0;
    background-color: var(--color-primary-container);
}

.cta-text {
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
    color: var(--color-primary-dark);
}

/* Footer */
footer {
    padding: var(--spacing-lg) 0;
    border-top: 1px solid var(--color-border);
}

footer p {
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

/* ================================
   Responsive - Tablet (≥768px)
   ================================ */
@media (min-width: 768px) {
    :root {
        --content-width: 580px;
        --padding-x: 2.5rem;
        --spacing-xl: 5rem;
    }

    h1 {
        font-size: 2.5rem;
        line-height: 1.15;
    }

    .subtitle {
        font-size: 1.25rem;
        line-height: 1.65;
    }

    .logo {
        font-size: 1.375rem;
        margin-bottom: var(--spacing-lg);
    }

    .logo-img {
        width: 48px;
        height: 48px;
        border-radius: 12px;
    }

    .problem h2,
    .how-it-works h2,
    .why h2 {
        font-size: 1.375rem;
    }

    .problem p {
        font-size: 1.125rem;
    }

    .step-content strong {
        font-size: 1.0625rem;
    }

    .step-content span {
        font-size: 1rem;
    }

    .benefits li {
        font-size: 1.0625rem;
    }

    .cta-text {
        font-size: 1.375rem;
    }

    .play-button {
        padding: 1rem 1.75rem;
    }

    .play-button-large {
        font-size: 1.25rem;
    }

    .section-nudge {
        font-size: 1.0625rem;
    }
}

/* ================================
   Responsive - Desktop (≥1024px)
   ================================ */
@media (min-width: 1024px) {
    :root {
        --max-width: 1140px;
        --content-width: 640px;
        --padding-x: 3.5rem;
        --spacing-xl: 6rem;
        --spacing-2xl: 8rem;
    }

    .hero {
        min-height: auto;
        padding: 3rem 0 var(--spacing-xl) 0;
    }

    .hero .container {
        gap: 0.5rem;
    }

    .logo {
        font-size: 1.5rem;
        gap: var(--spacing-md);
        margin-bottom: 2rem;
    }

    .logo-img {
        width: 56px;
        height: 56px;
        border-radius: 14px;
    }

    h1 {
        font-size: 3rem;
        letter-spacing: -0.025em;
        margin-bottom: 1rem;
    }

    .subtitle {
        font-size: 1.3125rem;
        line-height: 1.7;
        margin-bottom: 2rem;
    }

    .play-button {
        padding: 1.125rem 2.25rem;
        border-radius: 10px;
        box-shadow: 0 4px 14px rgba(107, 70, 193, 0.25);
    }

    .play-button:hover {
        box-shadow: 0 6px 20px rgba(107, 70, 193, 0.35);
    }

    .play-button-small {
        font-size: 0.6875rem;
    }

    .play-button-large {
        font-size: 1.3125rem;
    }

    .trust-copy {
        margin-top: 1.75rem;
        font-size: 0.9375rem;
    }

    .problem {
        padding: var(--spacing-xl) 0;
    }

    .problem h2,
    .how-it-works h2,
    .why h2 {
        font-size: 1.5rem;
        margin-bottom: var(--spacing-md);
    }

    .how-it-works h2,
    .why h2 {
        margin-bottom: var(--spacing-lg);
    }

    .problem p {
        font-size: 1.1875rem;
        line-height: 1.85;
    }

    .how-it-works {
        padding: var(--spacing-xl) 0;
    }

    .steps {
        gap: var(--spacing-lg);
    }

    .step-number {
        width: 2.5rem;
        height: 2.5rem;
        font-size: 1rem;
    }

    .step-content {
        gap: 0.375rem;
        padding-top: 0.375rem;
    }

    .step-content strong {
        font-size: 1.125rem;
    }

    .step-content span {
        font-size: 1.0625rem;
    }

    .section-nudge {
        margin-top: 2.5rem;
        font-size: 1.125rem;
    }

    .why {
        padding: var(--spacing-xl) 0;
    }

    .benefits {
        gap: var(--spacing-md);
    }

    .benefits li {
        font-size: 1.125rem;
        gap: 1rem;
    }

    .benefits svg {
        width: 22px;
        height: 22px;
    }

    .final-cta {
        padding: var(--spacing-xl) 0;
    }

    .cta-text {
        font-size: 1.5rem;
        margin-bottom: var(--spacing-md);
    }

    footer {
        padding: var(--spacing-xl) 0;
    }

    footer p {
        font-size: 0.9375rem;
    }
}

/* ================================
   Responsive - Large Desktop (≥1280px)
   ================================ */
@media (min-width: 1280px) {
    :root {
        --max-width: 1200px;
        --content-width: 680px;
        --padding-x: 4rem;
    }

    h1 {
        font-size: 3.25rem;
    }

    .subtitle {
        font-size: 1.375rem;
    }

    .logo {
        margin-bottom: 2.25rem;
    }

    .subtitle {
        margin-bottom: 2.25rem;
    }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    .play-button {
        transition: none;
    }
}