/* ===================================
   CSS Variables & Reset
   =================================== */
:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --secondary: #8b5cf6;
    --accent: #06b6d4;
    --bg-dark: #0f172a;
    --bg-darker: #020617;
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --glass-bg: rgba(15, 23, 42, 0.6);
    --glass-border: rgba(148, 163, 184, 0.1);
    --success: #10b981;
    --danger: #ef4444;
    --shadow-glow: 0 0 30px rgba(59, 130, 246, 0.3);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, var(--bg-darker) 0%, var(--bg-dark) 100%);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===================================
   Navigation Bar
   =================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--glass-border);
    padding: 1rem 0;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(15, 23, 42, 0.95);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 700;
    transition: transform 0.3s ease;
}

.navbar-brand:hover {
    transform: scale(1.05);
}

.brand-icon {
    font-size: 2rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.navbar-toggler {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.navbar-toggler span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 3px;
    transition: all 0.3s ease;
}

.navbar-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: var(--text-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(59, 130, 246, 0.6);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(59, 130, 246, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(139, 92, 246, 0.1) 0%, transparent 50%);
    z-index: 0;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 3s ease infinite;
}

@keyframes gradient-shift {
    0%, 100% { filter: hue-rotate(0deg); }
    50% { filter: hue-rotate(20deg); }
}

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.8;
}

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

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.floating-card {
    width: 300px;
    height: 300px;
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-glow);
    animation: float 6s ease-in-out infinite;
}

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

.crypto-icon {
    font-size: 8rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ===================================
   Market Section
   =================================== */
.market-section {
    padding: 5rem 0;
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.section-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.market-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.table-container {
    overflow-x: auto;
}

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

.crypto-table thead th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-secondary);
    border-bottom: 2px solid var(--glass-border);
}

.crypto-table tbody td {
    padding: 1.25rem 1rem;
    border-bottom: 1px solid var(--glass-border);
}

.crypto-table tbody tr {
    transition: background 0.3s ease;
}

.crypto-table tbody tr:hover {
    background: rgba(59, 130, 246, 0.05);
}

.crypto-name {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
}

.crypto-symbol {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.price-change {
    font-weight: 600;
    padding: 0.25rem 0.75rem;
    border-radius: 0.375rem;
}

.price-change.positive {
    color: var(--success);
    background: rgba(16, 185, 129, 0.1);
}

.price-change.negative {
    color: var(--danger);
    background: rgba(239, 68, 68, 0.1);
}

.loading-cell {
    text-align: center;
    padding: 3rem !important;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--glass-border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ===================================
   About Section
   =================================== */
.about-section {
    padding: 5rem 0;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-features {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.feature-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 1rem;
    padding: 2rem;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateX(10px);
    border-color: var(--primary);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.feature-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

.about-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.about-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

/* ===================================
   Footer
   =================================== */
.footer {
    padding: 2rem 0;
    border-top: 1px solid var(--glass-border);
    text-align: center;
}

.footer-text {
    color: var(--text-secondary);
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 768px) {
    .navbar-toggler {
        display: flex;
    }

    .navbar-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-dark);
        flex-direction: column;
        padding: 2rem;
        gap: 1rem;
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: all 0.3s ease;
        border-bottom: 1px solid var(--glass-border);
    }

    .navbar-menu.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: all;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-image {
        order: -1;
    }

    .floating-card {
        width: 200px;
        height: 200px;
    }

    .crypto-icon {
        font-size: 5rem;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .crypto-table {
        font-size: 0.875rem;
    }

    .crypto-table thead th,
    .crypto-table tbody td {
        padding: 0.75rem 0.5rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-description {
        font-size: 1rem;
    }

    .btn-lg {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.75rem;
    }
}
