:root {
    --color-primary: #0d47a1;
    --color-primary-light: #1565c0;
    --color-primary-dark: #0a3680;
    --color-accent: #00bcd4;
    --color-accent-light: #4dd0e1;
    --color-bg: #f8fafc;
    --color-surface: #ffffff;
    --color-text: #1e293b;
    --color-text-muted: #64748b;
    --color-border: #e2e8f0;
    --color-success: #10b981;
    --color-error: #ef4444;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.07), 0 2px 4px -2px rgb(0 0 0 / 0.05);
    --shadow-lg: 0 20px 40px -12px rgb(0 0 0 / 0.12);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
}

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

/* Header */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    color: var(--color-primary);
}

.lang-switch {
    display: inline-flex;
    align-items: center;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    text-decoration: none;
    color: var(--color-text);
    font-size: 0.875rem;
    font-weight: 500;
    transition: var(--transition);
}

.lang-switch:hover {
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}

/* Hero */
.hero {
    padding: 80px 0 60px;
    flex: 1;
}

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

.badge {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    color: #fff;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    border-radius: 100px;
    margin-bottom: 24px;
}

.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 700;
    line-height: 1.15;
    color: var(--color-primary-dark);
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 520px;
    margin-bottom: 40px;
    line-height: 1.7;
}

/* Notify Box */
.notify-box {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 32px;
    box-shadow: var(--shadow);
}

.notify-box h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--color-text);
}

.notify-box > p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    margin-bottom: 20px;
}

.notify-form {
    display: flex;
    gap: 12px;
}

.notify-form input[type="email"] {
    flex: 1;
    padding: 14px 18px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-family: var(--font);
    outline: none;
    transition: var(--transition);
}

.notify-form input[type="email"]:focus {
    border-color: var(--color-primary-light);
    box-shadow: 0 0 0 3px rgba(13, 71, 161, 0.1);
}

.notify-form button {
    padding: 14px 28px;
    background: var(--color-primary);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-weight: 600;
    font-family: var(--font);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.notify-form button:hover {
    background: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

/* Alert */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    margin-bottom: 16px;
    font-weight: 500;
}

.alert-success {
    background: #ecfdf5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert-error {
    background: #fef2f2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

/* Microsphere Animation */
.hero-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.microsphere-animation {
    position: relative;
    width: 380px;
    height: 380px;
}

.sphere {
    position: absolute;
    border-radius: 50%;
    opacity: 0.85;
}

.sphere-1 {
    width: 160px;
    height: 160px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle at 35% 35%, #4dd0e1, #0097a7);
    box-shadow: 0 0 60px rgba(0, 188, 212, 0.4), inset -20px -20px 40px rgba(0, 0, 0, 0.15);
    animation: float 6s ease-in-out infinite;
}

.sphere-2 {
    width: 90px;
    height: 90px;
    top: 15%;
    left: 20%;
    background: radial-gradient(circle at 35% 35%, #90caf9, #1565c0);
    box-shadow: 0 0 30px rgba(21, 101, 192, 0.35), inset -10px -10px 20px rgba(0, 0, 0, 0.12);
    animation: float 5s ease-in-out infinite 0.5s;
}

.sphere-3 {
    width: 70px;
    height: 70px;
    top: 20%;
    right: 15%;
    background: radial-gradient(circle at 35% 35%, #80deea, #00838f);
    box-shadow: 0 0 25px rgba(0, 131, 143, 0.3), inset -8px -8px 15px rgba(0, 0, 0, 0.12);
    animation: float 7s ease-in-out infinite 1s;
}

.sphere-4 {
    width: 50px;
    height: 50px;
    bottom: 20%;
    left: 15%;
    background: radial-gradient(circle at 35% 35%, #b3e5fc, #0288d1);
    box-shadow: 0 0 20px rgba(2, 136, 209, 0.3), inset -6px -6px 12px rgba(0, 0, 0, 0.1);
    animation: float 4.5s ease-in-out infinite 1.5s;
}

.sphere-5 {
    width: 40px;
    height: 40px;
    bottom: 25%;
    right: 25%;
    background: radial-gradient(circle at 35% 35%, #a5d6a7, #2e7d32);
    box-shadow: 0 0 15px rgba(46, 125, 50, 0.3), inset -5px -5px 10px rgba(0, 0, 0, 0.1);
    animation: float 5.5s ease-in-out infinite 2s;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) scale(1);
    }
    50% {
        transform: translateY(-20px) scale(1.05);
    }
}

.sphere-1 {
    animation: float-center 6s ease-in-out infinite;
}

@keyframes float-center {
    0%, 100% {
        transform: translate(-50%, -50%) scale(1);
    }
    50% {
        transform: translate(-50%, calc(-50% - 15px)) scale(1.04);
    }
}

/* Features */
.features {
    padding: 60px 0 80px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
}

.feature-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 32px 28px;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-accent-light);
}

.feature-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--color-primary);
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    line-height: 1.6;
}

/* Footer */
.footer {
    border-top: 1px solid var(--color-border);
    padding: 28px 0;
    margin-top: auto;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.footer-inner p {
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

.footer-inner a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.footer-inner a:hover {
    color: var(--color-accent);
}

/* Responsive */
@media (max-width: 992px) {
    .hero > .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-visual {
        order: -1;
    }

    .microsphere-animation {
        width: 280px;
        height: 280px;
    }

    .sphere-1 { width: 120px; height: 120px; }
    .sphere-2 { width: 70px; height: 70px; }
    .sphere-3 { width: 55px; height: 55px; }
    .sphere-4 { width: 40px; height: 40px; }
    .sphere-5 { width: 30px; height: 30px; }

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

@media (max-width: 600px) {
    .header-inner {
        height: 60px;
    }

    .logo-text {
        font-size: 1.25rem;
    }

    .hero {
        padding: 40px 0 30px;
    }

    .hero-content h1 {
        font-size: 2rem;
    }

    .notify-box {
        padding: 24px 20px;
    }

    .notify-form {
        flex-direction: column;
    }

    .notify-form button {
        width: 100%;
    }

    .footer-inner {
        flex-direction: column;
        gap: 8px;
        text-align: center;
    }
}