* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, Roboto, sans-serif;
}

body {
    background-color: #1a202c;
    background-image: linear-gradient(rgba(26, 32, 44, 0.75), rgba(26, 32, 44, 0.85)), url('image_yhTVIR.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(26, 32, 44, 0.9);
    z-index: 2000;
    display: flex;
    justify-content: center;
    align-items: center;
}

.loader-card {
    background: #2d3748;
    padding: 35px;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.5);
    text-align: center;
    width: 90%;
    max-width: 400px;
    border: 1px solid #4a5568;
}

.loader-card h3 {
    color: #fff;
    margin-bottom: 10px;
}

.loader-card p {
    font-size: 14px;
    color: #a0aec0;
    margin-bottom: 20px;
}

.progress-bar {
    background: #1a202c;
    border-radius: 20px;
    height: 12px;
    width: 100%;
    overflow: hidden;
    border: 1px solid #4a5568;
}

.progress-fill {
    background: linear-gradient(90deg, #4c51bf, #63b3ed);
    width: 0%;
    height: 100%;
    border-radius: 20px;
    transition: width 0.3s ease-in-out;
}

.navbar {
    background-color: #2d3748;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
    width: 100%;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    height: 60px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    color: #fff;
    text-decoration: none;
    font-weight: bold;
    font-size: 18px;
}

.nav-menu {
    list-style: none;
    display: flex;
    gap: 20px;
}

.nav-menu a {
    color: #cbd5e0;
    text-decoration: none;
    font-size: 15px;
    padding: 8px 12px;
    border-radius: 4px;
    transition: all 0.3s ease;
}

.nav-menu a:hover:not(.disabled-link) {
    background-color: #4a5568;
    color: #fff;
}

.nav-menu a.active {
    background-color: #4c51bf;
    color: #fff;
}

.nav-menu a.disabled-link {
    opacity: 0.4;
    cursor: not-allowed;
}

.container {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 100px 20px 40px 20px;
}

.card {
    background: #2d3748;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
    width: 100%;
    max-width: 500px;
    text-align: center;
    border: 1px solid #4a5568;
    backdrop-filter: blur(4px);
}

h2 {
    margin-bottom: 24px;
    color: #f7fafc;
    font-size: 20px;
    line-height: 1.5;
}

p {
    color: #cbd5e0;
    line-height: 1.6;
    margin-bottom: 24px;
}

.input-group {
    text-align: left;
    margin-bottom: 20px;
}

.input-group label {
    display: block;
    font-size: 14px;
    color: #a0aec0;
    margin-bottom: 6px;
}

.input-group input {
    width: 100%;
    padding: 12px;
    background: #1a202c;
    border: 1px solid #4a5568;
    border-radius: 6px;
    font-size: 16px;
    color: #fff;
}

.input-group input:focus {
    border-color: #63b3ed;
    outline: none;
}

.btn {
    display: inline-block;
    width: 100%;
    padding: 14px;
    background: #4c51bf;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.3s;
}

.btn:hover {
    background: #434190;
}

.btn.secondary {
    background: #4a5568;
    color: #edf2f7;
    margin-top: 10px;
}

.error-box {
    background-color: #742a2a;
    color: #fff;
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 20px;
    font-size: 14px;
}

.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 25px;
}

.stat-item {
    background: #1a202c;
    padding: 15px;
    border-radius: 6px;
    color: #edf2f7;
    border: 1px solid #4a5568;
}