:root {
    --bg-color: #ffffff;
    --bg-alt: #ffffff;
    --text-main: #111827;
    --text-muted: #6b7280;
    --primary: #000000;
    --primary-hover: #374151;
    --card-bg: #ffffff;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.02);
}

* {
    margin: 0; padding: 0; box-sizing: border-box; font-family: 'Inter', sans-serif;
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    line-height: 1.6;
}

/* Navbar */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    letter-spacing: -0.02em;
}
.logo span { color: var(--primary); }

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

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    font-size: 1rem;
}
.nav-links a:hover, .nav-links a.active { 
    color: var(--primary); 
}

.btn-login {
    background: white;
    color: var(--primary);
    padding: 0.6rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}
.btn-login:hover {
    background: var(--bg-alt);
    border-color: var(--border-color);
    box-shadow: var(--shadow-md);
}

/* Section Common */
section {
    padding: 6rem 5%;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--text-main);
    letter-spacing: -0.02em;
}
.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.125rem;
    margin-bottom: 4rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* Hero Section */
.hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: var(--bg-color);
    padding-top: 4rem;
}

.hero-content {
    max-width: 800px;
    animation: slideUp 0.8s ease-out;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.badge {
    display: inline-block;
    padding: 0.5rem 1.25rem;
    background: #f3f4f6;
    color: var(--primary);
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    border: 1px solid #e5e7eb;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    color: var(--text-main);
    letter-spacing: -0.03em;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
}

.btn-primary {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 1rem 2.5rem;
    border-radius: 12px;
    font-size: 1.125rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.39);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.23);
}

/* Features */
.features {
    background: var(--bg-color);
}
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
    text-align: left;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 70px;
    height: 70px;
    background: var(--bg-alt);
    border-radius: 16px;
    color: var(--primary);
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    font-weight: 700;
    color: var(--text-main);
}

.feature-card p {
    color: var(--text-muted);
}

/* How It Works (Timeline) */
.how-it-works {
    background: var(--bg-alt);
}

.steps-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.step-card {
    background: var(--card-bg);
    padding: 3rem 2rem 2rem;
    border-radius: 20px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    position: relative;
    text-align: center;
    transition: transform 0.3s ease;
}

.step-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.step-number {
    position: absolute;
    top: -24px;
    left: 50%;
    transform: translateX(-50%);
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.25rem;
    box-shadow: 0 4px 10px rgba(37,99,235,0.3);
    border: 4px solid var(--bg-alt);
}

.step-card h3 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
    font-weight: 700;
}
.step-card p {
    color: var(--text-muted);
    font-size: 1rem;
}

/* Profile Section */
.profile-section {
    background: var(--bg-color);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.profile-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 3rem;
    display: flex;
    align-items: center;
    gap: 3rem;
    max-width: 900px;
    width: 100%;
    box-shadow: var(--shadow-lg);
}

.profile-img {
    width: 220px;
    height: 220px;
    border-radius: 50%;
    object-fit: cover;
    border: 8px solid var(--bg-alt);
    box-shadow: var(--shadow-sm);
}

.profile-info {
    flex: 1;
}

.profile-info h3 {
    color: var(--primary);
    margin-bottom: 1.5rem;
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.profile-info p {
    color: var(--text-muted);
    margin-bottom: 0.75rem;
    font-size: 1.1rem;
}

.profile-info strong {
    color: var(--text-main);
    display: inline-block;
    width: 100px;
    font-weight: 600;
}

/* Extras for Features Page */
.features-page-header {
    text-align: center;
    padding: 6rem 5% 3rem;
    background: var(--bg-color);
}
.features-page-header h1 {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--text-main);
    margin-bottom: 1.5rem;
    letter-spacing: -0.03em;
}
.features-page-header p {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto;
}

/* Footer */
footer {
    background: #ffffff;
    color: #6b7280;
    border-top: 1px solid var(--border-color);
    text-align: center;
    padding: 2.5rem;
    margin-top: auto;
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .hero h1, .features-page-header h1 { font-size: 2.5rem; }
    .hero p { font-size: 1.1rem; }
    .profile-card { flex-direction: column; text-align: center; padding: 2rem; }
    .profile-info strong { width: auto; margin-right: 10px; }
    .step-number { left: 24px; transform: none; border-color: var(--card-bg); }
    .step-card { text-align: left; padding-top: 3.5rem; }
}