/* ===== CSS Variables ===== */
:root {
    --primary: #6C5CE7;
    --primary-light: #A29BFE;
    --primary-dark: #5A4BD1;
    --accent-pink: #FD79A8;
    --accent-pink-light: #FDCBDB;
    --accent-blue: #74B9FF;
    --accent-blue-light: #DFE6E9;
    --bg-white: #FFFFFF;
    --bg-light: #F8F9FE;
    --bg-card: #FFFFFF;
    --text-dark: #2D3436;
    --text-medium: #636E72;
    --text-light: #B2BEC3;
    --shadow-sm: 0 2px 8px rgba(108, 92, 231, 0.08);
    --shadow-md: 0 4px 20px rgba(108, 92, 231, 0.12);
    --shadow-lg: 0 8px 40px rgba(108, 92, 231, 0.16);
    --shadow-xl: 0 16px 60px rgba(108, 92, 231, 0.20);
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-main: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--text-dark);
    background: var(--bg-white);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

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

ul {
    list-style: none;
}

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

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

/* ===== Navbar ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: var(--transition);
    background: transparent;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: var(--shadow-sm);
    padding: 12px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.logo-icon {
    font-size: 1.8rem;
    color: var(--primary);
}

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

.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-medium);
    transition: var(--transition);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
    border-radius: 1px;
}

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

.nav-links a:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: var(--transition);
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #F8F9FE 0%, #EDE7F6 30%, #F3E5F5 60%, #FCE4EC 100%);
    overflow: hidden;
    padding-top: 80px;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 200%;
    background: radial-gradient(ellipse, rgba(108, 92, 231, 0.06) 0%, transparent 70%);
    pointer-events: none;
}

.hero-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
    padding: 60px 0;
    position: relative;
    z-index: 1;
}

.hero-content {
    flex: 1;
    max-width: 540px;
}

.hero-badge {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, var(--primary), var(--accent-pink));
    color: white;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 24px;
    letter-spacing: 1px;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary), var(--accent-pink));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.05rem;
    color: var(--text-medium);
    line-height: 1.8;
    margin-bottom: 36px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-family: var(--font-main);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    box-shadow: 0 4px 16px rgba(108, 92, 231, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(108, 92, 231, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary-light);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    transform: translateY(-2px);
}

/* Phone Mockup */
.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    max-width: 400px;
}

.phone-mockup {
    width: 280px;
    height: 560px;
    background: #1a1a2e;
    border-radius: 36px;
    padding: 12px;
    box-shadow: var(--shadow-xl), 0 0 0 2px rgba(255,255,255,0.1);
    position: relative;
    transform: perspective(1000px) rotateY(-5deg) rotateX(2deg);
    transition: var(--transition);
}

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

.phone-screen {
    width: 100%;
    height: 100%;
    background: var(--bg-light);
    border-radius: 28px;
    overflow: hidden;
    position: relative;
}

.phone-status-bar {
    display: flex;
    justify-content: space-between;
    padding: 8px 16px;
    font-size: 0.7rem;
    font-weight: 600;
    color: var(--text-dark);
    background: white;
}

.phone-app-preview {
    padding: 12px;
}

.preview-search {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    background: white;
    border-radius: 12px;
    font-size: 0.75rem;
    color: var(--text-light);
    margin-bottom: 16px;
    box-shadow: var(--shadow-sm);
}

.preview-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
    font-size: 0.85rem;
    font-weight: 600;
}

.preview-more {
    font-size: 0.7rem;
    color: var(--primary);
    font-weight: 500;
}

.preview-card {
    background: linear-gradient(135deg, #FCE4EC, #F3E5F5);
    border-radius: 16px;
    padding: 20px 16px;
    text-align: center;
    position: relative;
    margin-bottom: 12px;
}

.preview-card-heart {
    position: absolute;
    top: 10px;
    left: 12px;
    font-size: 1rem;
    color: var(--accent-pink);
}

.preview-card-letter {
    font-size: 2rem;
    color: var(--accent-pink);
    opacity: 0.3;
    margin-bottom: 4px;
}

.preview-card-name {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.preview-card-latin {
    font-size: 0.75rem;
    color: var(--primary);
    margin-bottom: 8px;
}

.preview-card-desc {
    font-size: 0.65rem;
    color: var(--text-medium);
    line-height: 1.5;
}

.preview-categories {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}

.preview-cat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 12px 8px;
    border-radius: 12px;
    font-size: 0.7rem;
}

.preview-cat.female {
    background: linear-gradient(135deg, #FCE4EC, #F8BBD0);
    color: #C2185B;
}

.preview-cat.male {
    background: linear-gradient(135deg, #E3F2FD, #BBDEFB);
    color: #1565C0;
}

.preview-cat-icon {
    font-size: 1.2rem;
}

.preview-cat-count {
    font-weight: 700;
    font-size: 0.8rem;
}

/* Hero Wave */
.hero-wave {
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    z-index: 2;
}

.hero-wave svg {
    width: 100%;
    height: auto;
    display: block;
}

/* ===== Section Common ===== */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 20px;
    background: linear-gradient(135deg, rgba(108, 92, 231, 0.1), rgba(253, 121, 168, 0.1));
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.section-desc {
    font-size: 1.05rem;
    color: var(--text-medium);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.8;
}

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

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

.feature-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: var(--transition);
    border: 1px solid rgba(108, 92, 231, 0.06);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent-pink));
    opacity: 0;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

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

.feature-icon-1 {
    background: linear-gradient(135deg, #EDE7F6, #D1C4E9);
    color: var(--primary);
}

.feature-icon-2 {
    background: linear-gradient(135deg, #FCE4EC, #F8BBD0);
    color: var(--accent-pink);
}

.feature-icon-3 {
    background: linear-gradient(135deg, #E3F2FD, #BBDEFB);
    color: #1976D2;
}

.feature-icon-4 {
    background: linear-gradient(135deg, #E8F5E9, #C8E6C9);
    color: #388E3C;
}

.feature-icon-5 {
    background: linear-gradient(135deg, #FFF3E0, #FFE0B2);
    color: #F57C00;
}

.feature-icon-6 {
    background: linear-gradient(135deg, #F3E5F5, #E1BEE7);
    color: #7B1FA2;
}

.feature-card h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-dark);
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-medium);
    line-height: 1.7;
}

/* ===== Screenshots Section ===== */
.screenshots {
    padding: 100px 0;
    background: var(--bg-light);
}

.screenshots-tabs {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 48px;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 10px 24px;
    border: 2px solid var(--accent-blue-light);
    background: white;
    border-radius: 24px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-medium);
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font-main);
}

.tab-btn:hover {
    border-color: var(--primary-light);
    color: var(--primary);
}

.tab-btn.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    box-shadow: 0 4px 12px rgba(108, 92, 231, 0.3);
}

.screenshots-content {
    position: relative;
}

.screenshot-panel {
    display: none;
    animation: fadeIn 0.5s ease;
}

.screenshot-panel.active {
    display: block;
}

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

.screenshot-showcase {
    display: flex;
    align-items: center;
    gap: 60px;
    background: white;
    border-radius: var(--radius-xl);
    padding: 48px;
    box-shadow: var(--shadow-md);
}

.screenshot-phone {
    flex-shrink: 0;
    width: 260px;
}

.screenshot-phone img {
    width: 100%;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
}

.screenshot-info h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-dark);
}

.screenshot-info > p {
    font-size: 1rem;
    color: var(--text-medium);
    line-height: 1.8;
    margin-bottom: 24px;
}

.screenshot-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.screenshot-features li {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    font-size: 0.9rem;
    color: var(--text-medium);
    line-height: 1.6;
}

.screenshot-features li::before {
    content: '✦';
    color: var(--primary);
    font-size: 0.8rem;
    flex-shrink: 0;
    margin-top: 2px;
}

/* ===== Stats Section ===== */
.stats {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary), #8E7CF0);
    position: relative;
    overflow: hidden;
}

.stats::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.05) 0%, transparent 50%);
    pointer-events: none;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 32px;
    position: relative;
    z-index: 1;
}

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

.stat-number {
    font-size: 2.8rem;
    font-weight: 700;
    color: white;
    margin-bottom: 8px;
    line-height: 1.2;
}

.stat-number::after {
    content: '+';
    font-size: 1.5rem;
    opacity: 0.7;
}

.stat-label {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.85);
    font-weight: 400;
}

/* ===== About Section ===== */
.about {
    padding: 100px 0;
    background: var(--bg-white);
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 40px;
}

.about-card {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 28px;
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

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

.about-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    background: linear-gradient(135deg, rgba(108, 92, 231, 0.1), rgba(253, 121, 168, 0.1));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.about-info h4 {
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 500;
    margin-bottom: 4px;
}

.about-info p {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-dark);
}

.about-note {
    background: linear-gradient(135deg, rgba(108, 92, 231, 0.05), rgba(253, 121, 168, 0.05));
    border-radius: var(--radius-lg);
    padding: 28px 32px;
    border-left: 4px solid var(--primary);
}

.about-note p {
    font-size: 0.95rem;
    color: var(--text-medium);
    line-height: 1.8;
}

/* ===== Contact Section ===== */
.contact {
    padding: 100px 0;
    background: var(--bg-light);
}

.contact-card {
    background: linear-gradient(135deg, var(--primary), #8E7CF0, var(--accent-pink));
    border-radius: var(--radius-xl);
    padding: 60px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.contact-card::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -30%;
    width: 60%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 60%);
    pointer-events: none;
}

.contact-content {
    position: relative;
    z-index: 1;
}

.contact-content h2 {
    font-size: 2rem;
    font-weight: 700;
    color: white;
    margin-bottom: 12px;
}

.contact-content > p {
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 32px;
}

.contact-methods {
    display: flex;
    justify-content: center;
    gap: 24px;
    flex-wrap: wrap;
}

.contact-method {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 32px;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    color: white;
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
}

.contact-method:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.contact-method-icon {
    font-size: 1.3rem;
}

/* ===== Footer ===== */
.footer {
    padding: 48px 0;
    background: var(--text-dark);
    color: rgba(255, 255, 255, 0.7);
}

.footer-content {
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 12px;
}

.footer-brand .logo-icon {
    color: var(--primary-light);
}

.footer-desc {
    font-size: 0.9rem;
    margin-bottom: 20px;
}

.footer-copy {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.4);
}

/* ===== Back to Top ===== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-4px);
}

.back-to-top svg {
    width: 24px;
    height: 24px;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .hero-container {
        flex-direction: column;
        text-align: center;
    }

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

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

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

    .screenshot-showcase {
        flex-direction: column;
        padding: 32px;
        gap: 32px;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        gap: 20px;
        box-shadow: var(--shadow-md);
        border-radius: 0 0 var(--radius-md) var(--radius-md);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-title {
        font-size: 3rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

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

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

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

    .contact-card {
        padding: 40px 24px;
    }

    .phone-mockup {
        width: 240px;
        height: 480px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2.4rem;
    }

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

    .btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }

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

    .stat-number {
        font-size: 2rem;
    }

    .screenshots-tabs {
        gap: 8px;
    }

    .tab-btn {
        padding: 8px 16px;
        font-size: 0.8rem;
    }
}