:root {
    --primary-color: #6366f1;
    --secondary-color: #a855f7;
    --bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
    --card-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-glow: rgba(99, 102, 241, 0.5);
    --bg-image: url('deep_dark_bg.png');
    --transition-speed: 0.6s;
}

/* Theme definitions */
body.theme-deep-dark {
    --primary-color: #6366f1; --secondary-color: #a855f7;
    --bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
    --text-primary: #f8fafc; --text-secondary: #94a3b8;
    --bg-image: url('deep_dark_bg.png');
}
body.theme-pure-white {
    --primary-color: #2563eb; --secondary-color: #3b82f6;
    --bg-gradient: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    --card-bg: rgba(0, 0, 0, 0.05);
    --glass-border: rgba(0, 0, 0, 0.1);
    --text-primary: #1e293b; --text-secondary: #64748b;
    --bg-image: url('white_bg.png');
}
body.theme-forest {
    --primary-color: #10b981; --secondary-color: #059669;
    --bg-gradient: linear-gradient(135deg, #064e3b 0%, #022c22 100%);
    --text-primary: #ecfdf5; --text-secondary: #a7f3d0;
    --bg-image: url('forest_bg.png');
}
body.theme-cyberpunk {
    --primary-color: #f43f5e; --secondary-color: #ec4899;
    --bg-gradient: linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
    --text-primary: #fff1f2; --text-secondary: #fecdd3;
    --bg-image: url('cyberpunk_bg.png');
}
body.theme-ocean {
    --primary-color: #0ea5e9; --secondary-color: #0284c7;
    --bg-gradient: linear-gradient(135deg, #0c4a6e 0%, #082f49 100%);
    --text-primary: #f0f9ff; --text-secondary: #bae6fd;
    --bg-image: url('ocean_bg.png');
}
body.theme-vibrant-purple {
    --primary-color: #c084fc; --secondary-color: #a855f7;
    --bg-gradient: linear-gradient(135deg, #4c1d95 0%, #2e1065 100%);
    --text-primary: #faf5ff; --text-secondary: #e9d5ff;
    --bg-image: url('purple_bg.png');
}
body.theme-sunset {
    --primary-color: #fb923c; --secondary-color: #f97316;
    --bg-gradient: linear-gradient(135deg, #7c2d12 0%, #431407 100%);
    --text-primary: #fff7ed; --text-secondary: #fed7aa;
    --bg-image: url('sunset_bg.png');
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
}

body {
    background: var(--bg-gradient);
    background-image: 
        linear-gradient(rgba(0, 0, 0, 0.4), rgba(0, 0, 0, 0.4)),
        var(--bg-image);
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    background-repeat: no-repeat;
    min-height: 100vh;
    color: var(--text-primary);
    overflow-x: hidden;
    position: relative;
    transition: background 0.8s ease, color 0.5s ease;
}

body.theme-pure-white {
    background-image: 
        linear-gradient(rgba(255, 255, 255, 0.6), rgba(255, 255, 255, 0.6)),
        var(--bg-image);
}

/* Background Animated Circles */
.background-circles {
    position: fixed;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    top: 0; left: 0;
}

.circle {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.3;
    animation: drift 25s infinite alternate linear;
    transition: background 0.8s ease;
}

.circle-1 {
    width: 600px;
    height: 600px;
    background: var(--primary-color);
    top: -200px;
    left: -200px;
}

.circle-2 {
    width: 650px;
    height: 650px;
    background: var(--secondary-color);
    bottom: -250px;
    right: -200px;
    animation-delay: -7s;
}

@keyframes drift {
    0% { transform: translate(0, 0); }
    100% { transform: translate(300px, 150px); }
}

nav {
    padding: 30px 10%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    animation: fadeInDown 1s ease-out;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.theme-selector-container {
    display: flex;
    gap: 8px;
    background: var(--card-bg);
    padding: 8px;
    border-radius: 50px;
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
}

.theme-dot {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid transparent;
    transition: transform 0.2s ease, border-color 0.2s;
}

.theme-dot:hover {
    transform: scale(1.2);
}

.theme-dot.active {
    border-color: var(--text-primary);
}

.theme-switcher {
    width: 45px;
    height: 45px;
    border-radius: 12px;
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.theme-switcher:hover {
    transform: rotate(45deg);
    background: rgba(255, 255, 255, 0.1);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -1px;
}

.logo span {
    color: var(--primary-color);
}

main {
    padding: 20px 10% 80px;
}

.hero {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 100px;
    align-items: center;
    padding: 40px 0 100px;
}

.hero-content {
    animation: fadeInLeft 1s ease-out;
}

.badge {
    background: rgba(99, 102, 241, 0.15);
    color: var(--primary-color);
    padding: 6px 15px;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    border: 1px solid var(--glass-border);
}

h1 {
    font-size: 3.5rem;
    line-height: 1.1;
    margin: 25px 0;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 40px;
    max-width: 500px;
}

.cta-group {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.main-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 20px 40px;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    color: white;
    text-decoration: none;
    border-radius: 20px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: 0 10px 30px -5px var(--accent-glow);
    width: fit-content;
}

.main-btn svg {
    width: 24px;
}

.main-btn:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px -5px var(--accent-glow);
}

.subtext {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-left: 5px;
}

.hero-image {
    animation: fadeInRight 1.5s ease-out;
}

.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 10px;
    box-shadow: 0 50px 80px -30px rgba(0,0,0,0.6);
    transform: perspective(1000px) rotateY(-10deg) rotateX(5deg);
    transition: transform 0.5s ease;
}

.glass-card:hover {
    transform: perspective(1000px) rotateY(-5deg) rotateX(2deg);
}

#app-mockup {
    width: 100%;
    border-radius: 12px;
    display: block;
}

.features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.feature-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 25px;
    padding: 30px;
    text-align: center;
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    background: rgba(255, 255, 255, 0.08);
}

.icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.feature-card h3 {
    margin-bottom: 10px;
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

footer {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    border-top: 1px solid var(--glass-border);
}

/* Animations */
@keyframes fadeInLeft {
    from { opacity: 0; transform: translateX(-50px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes fadeInRight {
    from { opacity: 0; transform: translateX(50px); }
    to { opacity: 1; transform: translateX(0); }
}

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

/* Mobile Responsive */
@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 60px;
    }
    
    .hero-content p {
        margin: 25px auto 40px;
    }
    
    .cta-group {
        align-items: center;
    }
    
    .glass-card {
        transform: none;
    }
    
    h1 {
        font-size: 2.8rem;
    }
    
    .features {
        grid-template-columns: 1fr;
    }
}

/* Modal Styling */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.8);
    backdrop-filter: blur(8px);
}

.modal-content {
    background: var(--card-bg);
    margin: 10% auto;
    padding: 2.5rem;
    border: 1px solid var(--glass-border);
    width: 90%;
    max-width: 400px;
    border-radius: 20px;
    position: relative;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(20px);
}

.close-modal {
    color: var(--text-secondary);
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    position: absolute;
    right: 20px;
    top: 15px;
    transition: 0.3s;
}

.close-modal:hover {
    color: var(--primary-color);
}

.form-group {
    margin-bottom: 1.5rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 0.8rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 1rem;
    outline: none;
    transition: 0.3s;
}

.form-group input:focus {
    border-color: var(--primary-color);
    background: rgba(255, 255, 255, 0.1);
}