:root {
    /* Spark Mail Inspired Light Theme */
    --bg-color: #FFFFFF;
    --text-color: #111111;
    --text-secondary: #4b5563;
    --accent-color: #205EFF;
    /* Spark Blue */
    --accent-hover: #1649c7;
    --card-bg: #FFFFFF;
    --font-main: 'Inter', sans-serif;
    --transition: all 0.3s ease;
    --shadow-soft: 0 20px 40px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 30px 60px rgba(0, 0, 0, 0.1);
    --border-radius: 12px;
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

/* Typography */
h1,
h2,
h3 {
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.1;
    color: var(--text-color);
}

h1 {
    font-size: 4rem;
    margin-bottom: 1.5rem;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 1.125rem;
}

/* Layout Utilities */
.container {
    max-width: 1100px;
    /* Slightly tighter for cleaner look */
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 8rem 0;
}

.hidden {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(12px);
    z-index: 1000;
    padding: 1.25rem 0;
    border-bottom: 1px solid rgba(0, 0, 0, 0.03);
}

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

.logo {
    font-weight: 800;
    font-size: 1.25rem;
    color: var(--text-color);
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    gap: 2.5rem;
}

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

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

/* Hero Section */
.hero-section {
    min-height: 90vh;
    /* Adjust for more white space look */
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    background: radial-gradient(100% 100% at 50% 0%, rgba(240, 245, 255, 1) 0%, rgba(255, 255, 255, 1) 100%);
}

.hero-content {
    max-width: 650px;
    z-index: 2;
    padding-top: 4rem;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    border-radius: 8px;
    /* Slightly squarer than pill */
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    box-shadow: 0 4px 6px rgba(32, 94, 255, 0.15);
}

.primary-btn {
    background-color: var(--accent-color);
    color: #FFFFFF;
}

.primary-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(32, 94, 255, 0.25);
}

.secondary-btn {
    background-color: #FFFFFF;
    border: 1px solid #e5e5e5;
    color: var(--text-color);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
}

.secondary-btn:hover {
    border-color: #d4d4d4;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    max-width: 800px;
}

.about-text p {
    font-size: 1.35rem;
    line-height: 1.6;
    color: var(--text-color);
    font-weight: 400;
}

/* Apps Section */
.apps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
}

.app-card {
    background-color: var(--card-bg);
    padding: 3rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-soft);
    border: none;
    transition: var(--transition);
}

.app-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
}

.app-icon {
    width: 56px;
    height: 56px;
    margin-bottom: 2rem;
    color: var(--accent-color);
    background: rgba(32, 94, 255, 0.05);
    padding: 12px;
    border-radius: 12px;
}

.app-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

/* Contact Section */
#contact {
    text-align: center;
    background-color: #fafafa;
    /* Subtle offset */
}

.contact-text {
    max-width: 600px;
    margin: 0 auto 3rem;
}

/* Footer */
footer {
    padding: 4rem 0;
    text-align: center;
    border-top: 1px solid #f0f0f0;
    color: #9ca3af;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    h1 {
        font-size: 2.75rem;
    }

    .section {
        padding: 5rem 0;
    }

    .nav-links {
        display: none;
    }

    .hero-content {
        padding-top: 6rem;
    }
}