/* ===========================
   CSS Variables & Base Styles
   =========================== */

:root {
    /* Color Scheme: Sunshine Yellow & Sky Blue */
    --color-primary: #FFC107;
    --color-primary-dark: #FFA000;
    --color-secondary: #4FC3F7;
    --color-secondary-dark: #0288D1;
    --color-accent: #FF9800;
    --color-background: #FFFEF7;
    --color-surface: #FFFFFF;
    --color-text: #212121;
    --color-text-light: #616161;
    --color-border: #E0E0E0;
    
    /* Typography */
    --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-family-display: "Rounded Mplus 1c", "Nunito", "Quicksand", var(--font-family-base);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-pill: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 12px 24px rgba(0, 0, 0, 0.18);
    
    /* Header Height */
    --header-height-mobile: 56px;
    --header-height-desktop: 72px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family-base);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-background);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--color-secondary-dark);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--color-primary-dark);
}

button {
    font-family: inherit;
    cursor: pointer;
}

/* ===========================
   Header Styles
   =========================== */

.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background-color: var(--color-surface);
    box-shadow: var(--shadow-sm);
    height: var(--header-height-mobile);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.header-icon {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
}

.header-brand {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-text);
    display: none;
}

.header-nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.nav-link {
    display: none;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text);
    transition: color 0.2s ease;
}

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

.cta-button-small {
    background-color: var(--color-primary);
    color: var(--color-text);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-pill);
    font-weight: 600;
    font-size: 0.875rem;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: var(--shadow-sm);
}

.cta-button-small:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

/* Desktop Header */
@media (min-width: 768px) {
    .header {
        height: var(--header-height-desktop);
    }
    
    .header-brand {
        display: block;
    }
    
    .header-icon {
        width: 42px;
        height: 42px;
    }
    
    .nav-link {
        display: block;
    }
    
    .cta-button-small {
        font-size: 0.9375rem;
    }
}

/* ===========================
   Hero Section
   =========================== */

.hero {
    padding: var(--spacing-xl) var(--spacing-md);
    background: linear-gradient(135deg, rgba(255, 193, 7, 0.1) 0%, rgba(79, 195, 247, 0.1) 100%);
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    gap: var(--spacing-xl);
}

.hero-content {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero-icon {
    width: 96px;
    height: 96px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--spacing-md);
    animation: popIn 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.hero-title {
    font-family: var(--font-family-display);
    font-size: 2rem;
    font-weight: 800;
    line-height: 1.2;
    color: var(--color-text);
    margin-bottom: var(--spacing-sm);
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-subtitle {
    font-size: 1.0625rem;
    line-height: 1.6;
    color: var(--color-text-light);
    max-width: 600px;
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 0.6s ease 0.2s both;
}

.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeIn 0.8s ease 0.3s both;
}

.hero-banner {
    width: 100%;
    max-width: 500px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
}

/* Download Buttons */
.download-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    width: 100%;
    max-width: 400px;
    animation: fadeInUp 0.6s ease 0.3s both;
}

.download-button {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--color-text);
    color: var(--color-surface);
    border-radius: var(--radius-md);
    border: none;
    font-size: 0.875rem;
    font-weight: 600;
    box-shadow: var(--shadow-md);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    min-height: 56px;
    position: relative;
}

.download-button.google-play {
    background-color: var(--color-secondary-dark);
}

.download-button.google-play:hover {
    background-color: #0277BD;
    transform: translateY(-3px) scale(1.02);
    box-shadow: var(--shadow-lg);
}

.download-button.google-play:active {
    transform: translateY(-1px) scale(1.01);
}

.download-button.app-store.coming-soon {
    background-color: #2a2a2a;
    opacity: 0.55;
    filter: grayscale(0.6);
    cursor: not-allowed;
}

.button-icon {
    width: 28px;
    height: 28px;
    flex-shrink: 0;
}

.button-text {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    text-align: left;
}

.button-label {
    font-size: 0.6875rem;
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    opacity: 0.9;
}

.button-store {
    font-size: 1.0625rem;
    font-weight: 700;
}

.coming-soon-badge {
    position: absolute;
    top: -8px;
    right: -8px;
    background-color: var(--color-accent);
    color: var(--color-surface);
    font-size: 0.625rem;
    font-weight: 700;
    padding: 4px 8px;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-sm);
}

/* Desktop Hero */
@media (min-width: 768px) {
    .hero {
        padding: var(--spacing-2xl) var(--spacing-md);
    }
    
    .hero-container {
        grid-template-columns: 1fr 1fr;
        align-items: center;
        gap: var(--spacing-2xl);
    }
    
    .hero-content {
        text-align: left;
        align-items: flex-start;
    }
    
    .hero-icon {
        width: 120px;
        height: 120px;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    .download-buttons {
        flex-direction: row;
        max-width: none;
    }
    
    .download-button {
        padding: var(--spacing-md) var(--spacing-lg);
    }
}

/* ===========================
   Features Section
   =========================== */

.features {
    padding: var(--spacing-2xl) var(--spacing-md);
    background-color: var(--color-surface);
}

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

.section-title {
    font-family: var(--font-family-display);
    font-size: 2rem;
    font-weight: 800;
    text-align: center;
    color: var(--color-text);
    margin-bottom: var(--spacing-xl);
}

.features-grid {
    display: grid;
    gap: var(--spacing-md);
}

.feature-card {
    background: linear-gradient(135deg, rgba(255, 193, 7, 0.08) 0%, rgba(79, 195, 247, 0.08) 100%);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    animation: letterPop 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.feature-title {
    font-family: var(--font-family-display);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.feature-description {
    font-size: 0.9375rem;
    line-height: 1.6;
    color: var(--color-text-light);
}

/* Desktop Features */
@media (min-width: 768px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-lg);
    }
}

@media (min-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ===========================
   Download CTA Section
   =========================== */

.download-cta {
    padding: var(--spacing-2xl) var(--spacing-md);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: var(--color-surface);
}

.download-cta-container {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.download-cta-title {
    font-family: var(--font-family-display);
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.download-cta-subtitle {
    font-size: 1.125rem;
    line-height: 1.6;
    margin-bottom: var(--spacing-xl);
    color: var(--color-text);
    opacity: 0.9;
}

.download-buttons-large {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    max-width: 500px;
    margin: 0 auto;
}

.download-button-large {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg) var(--spacing-xl);
    background-color: var(--color-text);
    color: var(--color-surface);
    border-radius: var(--radius-xl);
    border: none;
    font-size: 1rem;
    font-weight: 700;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    min-height: 64px;
    position: relative;
}

.download-button-large.google-play {
    background-color: var(--color-surface);
    color: var(--color-text);
}

.download-button-large.google-play:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: var(--shadow-xl);
}

.download-button-large.google-play:active {
    transform: translateY(-2px) scale(1.01);
}

.download-button-large.app-store.coming-soon {
    background-color: #2a2a2a;
    color: var(--color-surface);
    opacity: 0.55;
    filter: grayscale(0.6);
    cursor: not-allowed;
}

/* Desktop Download CTA */
@media (min-width: 768px) {
    .download-cta-title {
        font-size: 2.5rem;
    }
    
    .download-buttons-large {
        flex-direction: row;
        max-width: none;
        justify-content: center;
    }
}

/* ===========================
   About Section
   =========================== */

.about {
    padding: var(--spacing-2xl) var(--spacing-md);
    background-color: var(--color-background);
}

.about-container {
    max-width: 800px;
    margin: 0 auto;
}

.about-text {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

.about-contact {
    font-size: 1rem;
    color: var(--color-text-light);
    margin-top: var(--spacing-lg);
}

.contact-link {
    color: var(--color-secondary-dark);
    font-weight: 600;
    text-decoration: underline;
}

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

/* ===========================
   Footer
   =========================== */

.footer {
    padding: var(--spacing-xl) var(--spacing-md);
    background-color: var(--color-text);
    color: var(--color-surface);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.footer-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-sm);
}

.footer-brand-name {
    font-size: 1.125rem;
    font-weight: 700;
}

.footer-links {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

.footer-link {
    color: var(--color-surface);
    font-size: 0.9375rem;
    opacity: 0.8;
    transition: opacity 0.2s ease;
}

.footer-link:hover {
    opacity: 1;
}

.footer-contact {
    font-size: 0.9375rem;
}

.footer-email {
    color: var(--color-primary);
    text-decoration: underline;
}

.footer-email:hover {
    color: var(--color-primary-dark);
}

.footer-copyright {
    font-size: 0.875rem;
    opacity: 0.7;
    margin-top: var(--spacing-sm);
}

/* Desktop Footer */
@media (min-width: 768px) {
    .footer-container {
        text-align: left;
        gap: var(--spacing-lg);
    }
    
    .footer-brand {
        justify-content: flex-start;
    }
    
    .footer-links {
        justify-content: flex-start;
    }
}

/* ===========================
   Sticky Bottom CTA (Mobile)
   =========================== */

.sticky-cta {
    display: block;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-sm);
    background-color: var(--color-surface);
    box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.15);
    z-index: 90;
    opacity: 0;
    transform: translateY(100%);
    transition: all 0.3s ease;
}

.sticky-cta.visible {
    opacity: 1;
    transform: translateY(0);
}

.sticky-cta-button {
    display: block;
    width: 100%;
    padding: var(--spacing-md);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    color: var(--color-text);
    font-size: 1rem;
    font-weight: 700;
    text-align: center;
    border-radius: var(--radius-pill);
    box-shadow: var(--shadow-md);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.sticky-cta-button:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-lg);
}

.sticky-cta-button:active {
    transform: scale(0.98);
}

/* Hide on desktop */
@media (min-width: 768px) {
    .sticky-cta {
        display: none;
    }
}

/* ===========================
   Animations
   =========================== */

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

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes popIn {
    0% {
        opacity: 0;
        transform: scale(0.5);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes letterPop {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.15);
    }
    100% {
        transform: scale(1);
    }
}

/* Scroll-triggered animations */
.feature-card {
    opacity: 0;
    transform: translateY(30px);
}

.feature-card.visible {
    animation: fadeInUp 0.6s ease forwards;
}