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

:root {
    --color-black: #000000;
    --color-white: #ffffff;
    --color-gray-50: #fafafa;
    --color-gray-100: #f5f5f5;
    --color-gray-200: #e5e5e5;
    --color-gray-300: #d4d4d4;
    --color-gray-400: #a3a3a3;
    --color-gray-500: #737373;
    --color-gray-600: #525252;
    --color-gray-700: #404040;
    --color-gray-800: #262626;
    --color-gray-900: #171717;

    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px -3px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 40px -4px rgba(0,0,0,0.1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-gray-900);
    background: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: 1.25rem; }

p {
    color: var(--color-gray-600);
}

a {
    color: inherit;
    text-decoration: none;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-primary {
    background: var(--color-black);
    color: var(--color-white);
}

.btn-primary:hover {
    background: var(--color-gray-800);
    transform: translateY(-1px);
}

/* ===== Navigation ===== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-gray-100);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-icon {
    font-size: 1.5rem;
}

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

.nav-links a {
    font-size: 0.9375rem;
    color: var(--color-gray-600);
    transition: color var(--transition-fast);
}

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

.nav-cta {
    display: block;
}

.nav-mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.nav-mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-black);
    transition: all var(--transition-fast);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 65px;
    left: 0;
    right: 0;
    background: var(--color-white);
    padding: 24px;
    flex-direction: column;
    gap: 16px;
    border-bottom: 1px solid var(--color-gray-200);
    z-index: 999;
}

.mobile-menu.active {
    display: flex;
}

@media (max-width: 768px) {
    .nav-links, .nav-cta {
        display: none;
    }

    .nav-mobile-toggle {
        display: flex;
    }
}

/* ===== Hero Section ===== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(180deg, var(--color-gray-50) 0%, var(--color-white) 100%);
}

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

.hero-badge {
    display: inline-block;
    padding: 8px 16px;
    background: var(--color-black);
    color: var(--color-white);
    font-size: 0.8125rem;
    font-weight: 500;
    border-radius: 100px;
    margin-bottom: 24px;
}

.hero-title {
    margin-bottom: 24px;
}

.hero-title .highlight {
    color: var(--color-gray-500);
}

.hero-description {
    font-size: 1.125rem;
    margin-bottom: 32px;
    max-width: 500px;
}

.hero-cta {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
}

.store-badge img {
    height: 48px;
    transition: transform var(--transition-fast);
}

.store-badge:hover img {
    transform: scale(1.05);
}

.hero-rating {
    display: flex;
    align-items: center;
    gap: 12px;
}

.stars {
    color: #FFB800;
    font-size: 1.125rem;
    letter-spacing: 2px;
}

.rating-text {
    font-size: 0.875rem;
    color: var(--color-gray-500);
}

/* Phone Mockup */
.hero-image {
    display: flex;
    justify-content: center;
}

.phone-mockup {
    position: relative;
}

.phone-frame {
    width: 280px;
    height: 580px;
    background: var(--color-black);
    border-radius: 40px;
    padding: 12px;
    box-shadow: var(--shadow-xl);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: var(--color-white);
    border-radius: 32px;
    padding: 24px 20px;
    overflow: hidden;
}

.app-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 24px;
}

.app-greeting {
    font-weight: 600;
    font-size: 1rem;
}

.app-date {
    font-size: 0.875rem;
    color: var(--color-gray-500);
}

.app-score {
    text-align: center;
    margin-bottom: 24px;
}

.score-circle {
    width: 120px;
    height: 120px;
    margin: 0 auto 12px;
    background: linear-gradient(135deg, var(--color-gray-900) 0%, var(--color-gray-700) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.score-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-white);
}

.score-label {
    font-size: 0.8125rem;
    color: var(--color-gray-500);
}

.app-insight {
    display: flex;
    gap: 12px;
    background: var(--color-gray-50);
    padding: 16px;
    border-radius: 12px;
    margin-bottom: 16px;
}

.insight-icon {
    font-size: 1.5rem;
}

.insight-text strong {
    display: block;
    font-size: 0.8125rem;
    margin-bottom: 4px;
}

.insight-text p {
    font-size: 0.8125rem;
    color: var(--color-gray-600);
    margin: 0;
}

.app-streak {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px;
    background: linear-gradient(135deg, #FF6B35 0%, #FF8C42 100%);
    border-radius: 12px;
    color: var(--color-white);
    font-weight: 600;
    font-size: 0.9375rem;
}

@media (max-width: 968px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-description {
        margin-left: auto;
        margin-right: auto;
    }

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

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

    .hero-image {
        order: -1;
    }

    .phone-frame {
        width: 240px;
        height: 500px;
    }
}

/* ===== Social Proof Bar ===== */
.social-proof {
    padding: 40px 0;
    background: var(--color-gray-900);
}

.proof-items {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 48px;
}

.proof-item {
    text-align: center;
}

.proof-number {
    display: block;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-white);
    margin-bottom: 4px;
}

.proof-label {
    font-size: 0.875rem;
    color: var(--color-gray-400);
}

.proof-divider {
    width: 1px;
    height: 40px;
    background: var(--color-gray-700);
}

@media (max-width: 640px) {
    .proof-items {
        flex-direction: column;
        gap: 24px;
    }

    .proof-divider {
        width: 60px;
        height: 1px;
    }
}

/* ===== Problem Section ===== */
.problem {
    padding: 100px 0;
}

.section-title {
    margin-bottom: 16px;
}

.section-description {
    font-size: 1.125rem;
    max-width: 700px;
    margin-bottom: 48px;
}

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

.problem-card {
    padding: 32px;
    background: var(--color-gray-50);
    border-radius: 16px;
    border: 1px solid var(--color-gray-200);
}

.problem-icon {
    font-size: 1.5rem;
    margin-bottom: 16px;
}

.problem-card h3 {
    margin-bottom: 8px;
}

.problem-card p {
    font-size: 0.9375rem;
}

@media (max-width: 768px) {
    .problem-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== Features Section ===== */
.features {
    padding: 100px 0;
    background: var(--color-gray-50);
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 60px;
}

.section-header .section-description {
    margin-bottom: 0;
}

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

.features-cards {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.feature-card {
    display: flex;
    gap: 16px;
    padding: 24px;
    background: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: 16px;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.feature-card:hover {
    border-color: var(--color-gray-300);
}

.feature-card.active {
    background: var(--color-white);
    border-color: var(--color-black);
    transform: scale(1.02);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 1.75rem;
    flex-shrink: 0;
}

.feature-content h3 {
    margin-bottom: 8px;
}

.feature-content p {
    font-size: 0.9375rem;
    margin: 0;
}

.features-preview {
    display: flex;
    justify-content: center;
}

.features-preview .phone-frame {
    width: 300px;
    height: 620px;
}

.features-preview .phone-screen {
    position: relative;
}

.feature-screen {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 24px 20px;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-fast);
}

.feature-screen.active {
    opacity: 1;
    visibility: visible;
}

.screen-header {
    font-weight: 600;
    font-size: 1.25rem;
    margin-bottom: 24px;
    text-align: center;
}

/* Dashboard Screen */
.dashboard-score {
    text-align: center;
    margin-bottom: 32px;
}

.big-score {
    font-size: 4rem;
    font-weight: 700;
    line-height: 1;
}

.score-trend {
    font-size: 0.875rem;
    color: #22c55e;
    font-weight: 500;
}

.dashboard-metrics {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.metric {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.metric-label {
    font-size: 0.8125rem;
    color: var(--color-gray-600);
}

.metric-bar {
    height: 8px;
    background: var(--color-gray-200);
    border-radius: 4px;
    overflow: hidden;
}

.metric-fill {
    height: 100%;
    background: var(--color-black);
    border-radius: 4px;
}

/* Frameworks Screen */
.framework-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.framework-item {
    display: flex;
    gap: 12px;
    padding: 16px;
    background: var(--color-gray-50);
    border-radius: 12px;
}

.fw-icon {
    font-size: 1.5rem;
}

.fw-content strong {
    display: block;
    font-size: 0.9375rem;
    margin-bottom: 2px;
}

.fw-content p {
    font-size: 0.8125rem;
    color: var(--color-gray-500);
    margin: 0;
}

/* Coaching Screen */
.chat-container {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.chat-bubble {
    padding: 14px 16px;
    border-radius: 16px;
    font-size: 0.875rem;
    line-height: 1.5;
}

.chat-bubble.user {
    background: var(--color-black);
    color: var(--color-white);
    border-bottom-right-radius: 4px;
    margin-left: 20px;
}

.chat-bubble.ai {
    background: var(--color-gray-100);
    color: var(--color-gray-800);
    border-bottom-left-radius: 4px;
    margin-right: 20px;
}

/* Habits Screen */
.habits-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-bottom: 20px;
}

.habit-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 16px;
    background: var(--color-gray-50);
    border-radius: 12px;
}

.habit-check {
    width: 24px;
    height: 24px;
    border: 2px solid var(--color-gray-300);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
    color: var(--color-white);
    flex-shrink: 0;
}

.habit-item.done .habit-check {
    background: var(--color-black);
    border-color: var(--color-black);
}

.habit-name {
    font-size: 0.9375rem;
}

.streak-banner {
    background: linear-gradient(135deg, #FF6B35 0%, #FF8C42 100%);
    color: var(--color-white);
    padding: 14px;
    border-radius: 12px;
    text-align: center;
    font-weight: 600;
}

@media (max-width: 968px) {
    .features-grid {
        grid-template-columns: 1fr;
    }

    .features-preview {
        order: -1;
    }
}

/* ===== Testimonials Section ===== */
.testimonials {
    padding: 100px 0;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.testimonial-card {
    padding: 32px;
    background: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: 16px;
}

.testimonial-card.featured {
    grid-column: span 2;
    background: var(--color-gray-900);
    border-color: var(--color-gray-900);
}

.testimonial-card.featured .testimonial-content p {
    color: var(--color-gray-300);
    font-size: 1.25rem;
}

.testimonial-card.featured .author-info strong {
    color: var(--color-white);
}

.testimonial-card.featured .author-info span {
    color: var(--color-gray-400);
}

.testimonial-content p {
    font-size: 1rem;
    line-height: 1.7;
    margin-bottom: 24px;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 12px;
}

.author-avatar {
    width: 48px;
    height: 48px;
    background: var(--color-gray-200);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.875rem;
}

.testimonial-card.featured .author-avatar {
    background: var(--color-gray-700);
    color: var(--color-white);
}

.author-info {
    display: flex;
    flex-direction: column;
}

.author-info strong {
    font-size: 0.9375rem;
}

.author-info span {
    font-size: 0.8125rem;
    color: var(--color-gray-500);
}

@media (max-width: 768px) {
    .testimonials-grid {
        grid-template-columns: 1fr;
    }

    .testimonial-card.featured {
        grid-column: span 1;
    }

    .testimonial-card.featured .testimonial-content p {
        font-size: 1.0625rem;
    }
}

/* ===== How It Works ===== */
.how-it-works {
    padding: 100px 0;
    background: var(--color-gray-50);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.step {
    text-align: center;
    padding: 32px;
}

.step-number {
    width: 56px;
    height: 56px;
    margin: 0 auto 20px;
    background: var(--color-black);
    color: var(--color-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
}

.step h3 {
    margin-bottom: 12px;
}

.step p {
    font-size: 0.9375rem;
}

@media (max-width: 768px) {
    .steps-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== FAQ Section ===== */
.faq {
    padding: 100px 0;
}

.faq-grid {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.faq-item {
    border: 1px solid var(--color-gray-200);
    border-radius: 12px;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 20px 24px;
    background: var(--color-white);
    border: none;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    text-align: left;
    font-size: 1rem;
    font-weight: 500;
    font-family: inherit;
    transition: background var(--transition-fast);
}

.faq-question:hover {
    background: var(--color-gray-50);
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--color-gray-400);
    transition: transform var(--transition-fast);
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

.faq-answer p {
    padding: 0 24px 20px;
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* ===== CTA Section ===== */
.cta-section {
    padding: 100px 0;
    background: var(--color-gray-900);
    text-align: center;
}

.cta-content h2 {
    color: var(--color-white);
    margin-bottom: 16px;
}

.cta-content > p {
    color: var(--color-gray-400);
    font-size: 1.125rem;
    margin-bottom: 32px;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 24px;
}

.cta-note {
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

@media (max-width: 480px) {
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
}

/* ===== Footer ===== */
.footer {
    padding: 60px 0 32px;
    background: var(--color-black);
}

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
    padding-bottom: 40px;
    border-bottom: 1px solid var(--color-gray-800);
}

.footer-brand .nav-logo {
    color: var(--color-white);
    margin-bottom: 16px;
}

.footer-brand p {
    color: var(--color-gray-500);
    font-size: 0.9375rem;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.footer-column h4 {
    color: var(--color-white);
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-column a {
    display: block;
    color: var(--color-gray-500);
    font-size: 0.875rem;
    margin-bottom: 12px;
    transition: color var(--transition-fast);
}

.footer-column a:hover {
    color: var(--color-white);
}

.footer-bottom {
    padding-top: 32px;
}

.footer-bottom p {
    color: var(--color-gray-600);
    font-size: 0.875rem;
}

@media (max-width: 768px) {
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

@media (max-width: 480px) {
    .footer-links {
        grid-template-columns: 1fr;
    }
}