/* ===== CSS Variables ===== */
:root {
    /* Colors - Matching Login Screen */
    --color-primary: #F5A623;
    --color-primary-dark: #C27B0E;
    --color-primary-light: #F7B750;
    --color-accent: #F5A623;
    --color-accent-light: #FBBF24;

    /* Backgrounds - Slate like login */
    --bg-cream: #f8fafc;
    --bg-card: rgba(255, 255, 255, 0.75);
    --bg-card-hover: rgba(255, 255, 255, 0.9);

    /* Text - Slate tones matching login */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    /* Borders */
    --border-light: rgba(0, 0, 0, 0.06);
    --border-radius: 16px;
    --border-radius-lg: 24px;
    --border-radius-full: 9999px;

    /* Spacing */
    --container-max: 1200px;
    --section-padding: 100px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
}

/* ===== Reset & Base ===== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-cream);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
}

/* ===== Background Decorations ===== */
.bg-orb {
    position: fixed;
    border-radius: 50%;
    filter: blur(60px);
    pointer-events: none;
    z-index: -1;
}

.bg-orb-1 {
    width: 500px;
    height: 500px;
    background: rgba(245, 166, 35, 0.35);
    top: -150px;
    right: -150px;
    animation: float 20s ease-in-out infinite;
}

.bg-orb-2 {
    width: 350px;
    height: 350px;
    background: rgba(99, 102, 241, 0.25);
    top: 30%;
    left: -120px;
    animation: float 15s ease-in-out infinite reverse;
}

.bg-orb-3 {
    width: 300px;
    height: 300px;
    background: rgba(16, 185, 129, 0.25);
    bottom: -80px;
    right: 15%;
    animation: float 18s ease-in-out infinite;
}

@keyframes float {

    0%,
    100% {
        transform: translate(0, 0) scale(1);
    }

    33% {
        transform: translate(30px, -30px) scale(1.05);
    }

    66% {
        transform: translate(-20px, 20px) scale(0.95);
    }
}

/* ===== Container ===== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 16px 0;
    transition: var(--transition-base);
}

.navbar.scrolled {
    background: rgba(248, 250, 252, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-img {
    height: 40px;
    width: auto;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-fast);
}

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

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-family: inherit;
    font-weight: 600;
    text-decoration: none;
    border: none;
    cursor: pointer;
    transition: var(--transition-base);
    border-radius: var(--border-radius);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    color: white;
    box-shadow: 0 4px 14px rgba(245, 166, 35, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(245, 166, 35, 0.5);
}

.btn-secondary {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-light);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: var(--bg-card-hover);
    transform: translateY(-2px);
}

.btn-sm {
    padding: 10px 20px;
    font-size: 14px;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 16px;
}

.btn-icon {
    width: 20px;
    height: 20px;
}

/* ===== Hero Section ===== */
.hero {
    padding: 140px 0 var(--section-padding);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    max-width: 560px;
}

.hero-logo-container {
    margin-bottom: 32px;
    display: flex;
    justify-content: center;
}

.hero-logo-large {
    height: 120px;
    width: auto;
    filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.1));
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    padding: 8px 16px;
    border-radius: var(--border-radius-full);
    border: 1px solid var(--border-light);
    font-size: 14px;
    font-weight: 500;
    color: var(--color-primary-dark);
    margin-bottom: 24px;
}

.badge-icon {
    font-size: 16px;
}

.hero-title {
    font-size: clamp(40px, 5vw, 64px);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

.gradient-text {
    display: block;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 32px;
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 24px;
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-primary);
}

.stat-label {
    font-size: 14px;
    color: var(--text-muted);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border-light);
}

/* Hero Visual - Phone Mockup */
.hero-visual {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.phone-mockup {
    width: 320px;
    background: linear-gradient(145deg, #1F2937, #374151);
    border-radius: 40px;
    padding: 12px;
    box-shadow: var(--shadow-xl), 0 0 0 1px rgba(255, 255, 255, 0.1) inset;
    transform: perspective(1000px) rotateY(-5deg) rotateX(5deg);
    transition: var(--transition-slow);
}

.phone-mockup:hover {
    transform: perspective(1000px) rotateY(0deg) rotateX(0deg);
}

.phone-screen {
    background: var(--bg-cream);
    border-radius: 32px;
    overflow: hidden;
    aspect-ratio: 9/16;
}

.app-preview {
    height: 100%;
    display: flex;
    flex-direction: column;
    padding: 20px;
}

.preview-header {
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-light);
    margin-bottom: 20px;
}

.preview-title {
    font-size: 20px;
    font-weight: 700;
}

.preview-question {
    flex: 1;
}

.question-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
    color: white;
    padding: 6px 12px;
    border-radius: var(--border-radius-full);
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 16px;
}

.question-text {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 20px;
    line-height: 1.5;
}

.options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.option {
    padding: 12px 16px;
    background: white;
    border: 1px solid var(--border-light);
    border-radius: 12px;
    font-size: 14px;
    transition: var(--transition-fast);
}

.option.correct {
    background: linear-gradient(135deg, rgba(245, 166, 35, 0.1), rgba(245, 166, 35, 0.2));
    border-color: var(--color-primary);
    color: var(--color-primary-dark);
    font-weight: 600;
}

.preview-progress {
    margin-top: auto;
    padding-top: 20px;
}

.progress-bar {
    height: 8px;
    background: rgba(245, 166, 35, 0.2);
    border-radius: var(--border-radius-full);
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-fill {
    height: 100%;
    width: 70%;
    background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
    border-radius: var(--border-radius-full);
}

.progress-text {
    font-size: 12px;
    color: var(--text-muted);
}

/* ===== Features Section ===== */
.features {
    padding: var(--section-padding) 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: clamp(32px, 4vw, 48px);
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-light);
    border-radius: var(--border-radius-lg);
    padding: 32px;
    transition: var(--transition-base);
    opacity: 0;
    transform: translateY(20px);
}

.feature-card.animate-in {
    opacity: 1;
    transform: translateY(0);
}

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

.feature-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    stroke: white;
}

.feature-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.feature-description {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===== Topics Section ===== */
.topics {
    padding: var(--section-padding) 0;
    background: linear-gradient(180deg, transparent, rgba(245, 166, 35, 0.05));
}

.topics-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
}

.topic-pill {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-light);
    padding: 12px 24px;
    border-radius: var(--border-radius-full);
    font-size: 15px;
    font-weight: 500;
    transition: var(--transition-base);
    opacity: 0;
    transform: scale(0.9);
}

.topic-pill.animate-in {
    opacity: 1;
    transform: scale(1);
}

.topic-pill:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    transform: scale(1.05);
}

/* ===== Download Section ===== */
.download {
    padding: var(--section-padding) 0;
}

.download-card {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    border-radius: var(--border-radius-lg);
    padding: 80px 60px;
    position: relative;
    overflow: hidden;
    opacity: 0;
    transform: translateY(20px);
}

.download-card.animate-in {
    opacity: 1;
    transform: translateY(0);
}

.download-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.download-title {
    font-size: clamp(32px, 4vw, 44px);
    font-weight: 800;
    color: white;
    margin-bottom: 16px;
}

.download-subtitle {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 40px;
}

.store-buttons {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.store-btn {
    display: flex;
    align-items: center;
    gap: 12px;
    background: rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    padding: 14px 24px;
    border-radius: 14px;
    color: white;
    text-decoration: none;
    transition: var(--transition-base);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.store-btn:hover {
    background: rgba(0, 0, 0, 0.5);
    transform: translateY(-2px);
}

.store-icon {
    width: 28px;
    height: 28px;
}

.store-text {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.store-label {
    font-size: 11px;
    opacity: 0.8;
}

.store-name {
    font-size: 18px;
    font-weight: 600;
}

.download-decoration {
    position: absolute;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
}

.deco-circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
}

.deco-circle-1 {
    width: 400px;
    height: 400px;
    top: -200px;
    right: -100px;
}

.deco-circle-2 {
    width: 300px;
    height: 300px;
    bottom: -150px;
    left: -50px;
}

/* ===== Footer ===== */
.footer {
    background: var(--text-primary);
    padding: 60px 0 30px;
    color: white;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
}

.footer-logo {
    height: 36px;
    width: auto;
    object-fit: contain;
    filter: brightness(0) saturate(100%) invert(100%) sepia(0%) saturate(0%) hue-rotate(0deg) brightness(100%) contrast(100%);
}

.footer-tagline {
    font-size: 14px;
    opacity: 0.7;
}

.footer-links {
    display: flex;
    gap: 32px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 14px;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    font-size: 14px;
    opacity: 0.5;
}

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-cta {
        justify-content: center;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-visual {
        order: -1;
    }

    .phone-mockup {
        width: 280px;
        transform: none;
    }

    .hero-logo-large {
        height: 80px;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 60px;
    }

    .nav-links a:not(.btn) {
        display: none;
    }

    .hero {
        padding-top: 100px;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .hero-stats {
        flex-wrap: wrap;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .download-card {
        padding: 60px 30px;
    }

    .store-buttons {
        flex-direction: column;
        align-items: center;
    }

    .footer-content {
        flex-direction: column;
        gap: 30px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .phone-mockup {
        width: 240px;
    }

    .topic-pill {
        padding: 10px 18px;
        font-size: 14px;
    }
}