:root {
    /* Green & Blue Theme Palette */
    --primary-color: #00ff88; /* Vibrant Green */
    --secondary-color: #00ccff; /* Vibrant Blue */
    --accent-color: #1a1a2e; /* Dark Blue Background */
    --bg-dark: #0f0f1a; /* Deep Dark Background */
    --bg-card: rgba(26, 26, 46, 0.8); /* Glassmorphic Card */
    --text-main: #ffffff;
    --text-muted: #a0a0b0;
    --success: #00ff88;
    --danger: #ff4d4d;
    --warning: #ffcc00;
    
    --sidebar-width: 260px;
    --header-height: 70px;
    --border-radius: 12px;
    --glass-border: 1px solid rgba(255, 255, 255, 0.1);
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    overflow-x: hidden;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-dark);
}
::-webkit-scrollbar-thumb {
    background: linear-gradient(to bottom, var(--primary-color), var(--secondary-color));
    border-radius: 4px;
}

/* Layout */
.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border-right: var(--glass-border);
    padding: 20px;
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    z-index: 100;
}

.logo {
    font-size: 24px;
    font-weight: 800;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 40px;
    letter-spacing: 1px;
}

.nav-links {
    list-style: none;
}

.nav-item {
    margin-bottom: 15px;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 12px 15px;
    color: var(--text-muted);
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: all 0.3s ease;
    font-weight: 500;
}

.nav-link i {
    margin-right: 12px;
    font-size: 20px;
}

.nav-link:hover, .nav-link.active {
    background: linear-gradient(90deg, rgba(0, 255, 136, 0.1), rgba(0, 204, 255, 0.1));
    color: var(--primary-color);
    border-left: 3px solid var(--primary-color);
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    padding: 20px;
}

/* Header */
.header {
    height: var(--header-height);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
    margin-bottom: 30px;
    background: var(--bg-card);
    border-radius: var(--border-radius);
    border: var(--glass-border);
}

.user-stats {
    display: flex;
    align-items: center;
    gap: 20px;
}

.coin-balance {
    background: rgba(0, 255, 136, 0.1);
    color: var(--primary-color);
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
    border: 1px solid rgba(0, 255, 136, 0.3);
}

.profile-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    justify-content: center;
    align-items: center;
    color: #000;
    font-weight: bold;
    cursor: pointer;
}

/* Sections */
.section {
    display: none;
    animation: fadeIn 0.5s ease;
}

.section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Offer Grid */
.offer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.offer-card {
    background: var(--bg-card);
    border: var(--glass-border);
    border-radius: var(--border-radius);
    padding: 20px;
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.offer-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 255, 136, 0.1);
    border-color: var(--primary-color);
}

.offer-card img {
    width: 80px;
    height: 80px;
    border-radius: 15px;
    margin-bottom: 15px;
    object-fit: cover;
}

.offer-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 5px;
}

.offer-reward {
    color: var(--secondary-color);
    font-weight: 700;
    font-size: 16px;
    margin-top: 10px;
}

.btn-start {
    margin-top: 15px;
    width: 100%;
    padding: 10px;
    border: none;
    border-radius: 8px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    color: #000;
    font-weight: 700;
    cursor: pointer;
    transition: opacity 0.3s;
}

.btn-start:hover {
    opacity: 0.9;
}

/* Admin Panel Styles */
.admin-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: var(--bg-card);
    padding: 25px;
    border-radius: var(--border-radius);
    border: var(--glass-border);
    text-align: center;
}

.stat-value {
    font-size: 32px;
    font-weight: 800;
    color: var(--primary-color);
    margin-top: 10px;
}

.table-container {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    padding: 20px;
    border: var(--glass-border);
    overflow-x: auto;
}

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

th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

th {
    color: var(--text-muted);
    font-weight: 500;
}

.btn-action {
    padding: 5px 10px;
    border-radius: 5px;
    border: none;
    cursor: pointer;
    font-size: 12px;
    margin-right: 5px;
}

.btn-approve { background: var(--success); color: #000; }
.btn-reject { background: var(--danger); color: #fff; }

/* Forms */
.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: var(--text-muted);
}

.form-control {
    width: 100%;
    padding: 12px;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: #fff;
}

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