:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary: #0f172a;
    --accent: #8b5cf6;
    --light: #f8fafc;
    --dark: #0f172a;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --gray: #94a3b8;
    --card-bg: #1e293b;
    --border: #334155;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: linear-gradient(135deg, #0f172a, #1e293b);
    color: var(--light);
    min-height: 100vh;
    padding-bottom: 2rem;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

/* Header Styles */
header {
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--light);
}

.logo i {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

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

.auth-buttons {
    display: flex;
    gap: 1rem;
}

.btn {
    padding: 0.6rem 1.2rem;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    border: none;
    font-size: 0.9rem;
}

.btn-primary {
    background: var(--primary);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--primary);
    color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

/* Hero Section */
.hero {
    padding: 3rem 0;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(to right, #8b5cf6, #2563eb);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.1rem;
    color: var(--gray);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 1.5rem;
}

/* Dashboard */
.dashboard {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--border);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.card-title {
    font-size: 1.2rem;
    font-weight: 600;
}

.card-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(37, 99, 235, 0.2);
    color: var(--primary);
}

/* Portfolio Summary */
.portfolio-summary {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.summary-item {
    display: flex;
    justify-content: space-between;
}

.summary-label {
    color: var(--gray);
}

.summary-value {
    font-weight: 600;
}

.positive {
    color: var(--success);
}

.negative {
    color: var(--danger);
}

/* Cryptocurrency List */
.crypto-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.crypto-item {
    display: flex;
    align-items: center;
    padding: 1rem;
    border-radius: 8px;
    background: rgba(30, 41, 59, 0.7);
    transition: transform 0.3s;
    cursor: pointer;
}

.crypto-item:hover {
    transform: translateY(-3px);
    background: rgba(30, 41, 59, 0.9);
}

.crypto-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--dark);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 1rem;
    font-size: 1.2rem;
}

.crypto-info {
    flex: 1;
}

.crypto-name {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.crypto-symbol {
    color: var(--gray);
    font-size: 0.9rem;
}

.crypto-price {
    font-weight: 600;
}

.crypto-change {
    margin-left: 1rem;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.85rem;
}

/* Investment Form */
.investment-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 500;
}

.form-control {
    padding: 0.75rem;
    border-radius: 6px;
    background: rgba(15, 23, 42, 0.5);
    border: 1px solid var(--border);
    color: var(--light);
    font-size: 1rem;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
}

.investment-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

/* Market Overview */
.market-overview {
    margin: 2rem 0;
}

.market-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.market-filters {
    display: flex;
    gap: 1rem;
}

.filter-btn {
    padding: 0.5rem 1rem;
    background: rgba(30, 41, 59, 0.7);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--light);
    cursor: pointer;
    transition: all 0.3s;
}

.filter-btn.active {
    background: var(--primary);
    border-color: var(--primary);
}

.market-table {
    width: 100%;
    border-collapse: collapse;
}

.market-table th {
    text-align: left;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
    color: var(--gray);
    font-weight: 500;
}

.market-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border);
}

.market-table tr:last-child td {
    border-bottom: none;
}

.market-table tr:hover {
    background: rgba(30, 41, 59, 0.5);
}

.crypto-cell {
    display: flex;
    align-items: center;
}

.crypto-cell-icon {
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background: var(--dark);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 0.75rem;
    font-size: 0.9rem;
}

.price-change {
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.85rem;
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem 0;
    color: var(--gray);
    margin-top: 3rem;
    border-top: 1px solid var(--border);
}

/* Responsive Design */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-links {
        gap: 1rem;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .investment-actions {
        flex-direction: column;
    }
}