/* Variables */
:root {
    --primary: #0d6efd;
    --primary-dark: #0b5ed7;
    --success: #198754;
    --warning: #ffc107;
    --card-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
}

/* Global Styles */
body {
    font-family: 'Inter', sans-serif;
    background-color: #f8f9fa;
    color: #212529;
    padding-top: 56px;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.navbar-brand {
    font-weight: 700;
    color: var(--primary);
}

.nav-link {
    font-weight: 500;
    color: #6c757d;
    position: relative;
    padding: 0.5rem 1rem;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 1rem;
    right: 1rem;
    height: 2px;
    background: var(--primary);
    transform: scaleX(0);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    transform: scaleX(1);
}

/* Main Section */
.main-section {
    padding: 5rem 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
}

.main-card {
    border: none;
    border-radius: 1rem;
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.main-card .card-header {
    background: white;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    padding: 1.5rem;
}

.main-card .card-header h3 {
    margin: 0;
    font-size: 1.25rem;
    font-weight: 600;
}

.security-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.25rem 0.75rem;
    background: rgba(25, 135, 84, 0.1);
    color: var(--success);
    border-radius: 2rem;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Upload Zone */
.upload-zone {
    border: 2px dashed #dee2e6;
    border-radius: 1rem;
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    position: relative;
}

.upload-zone:hover,
.upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(13, 110, 253, 0.02);
}

.upload-zone input[type="file"] {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

.upload-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 1rem;
    background: rgba(13, 110, 253, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.upload-icon i {
    font-size: 24px;
    color: var(--primary);
}

.upload-zone h5 {
    margin-bottom: 0.5rem;
    font-weight: 600;
}

/* Form Elements */
.form-floating > .form-control {
    height: calc(3.5rem + 2px);
    padding: 1rem 0.75rem;
}

.form-floating > label {
    padding: 1rem 0.75rem;
}

.btn {
    font-weight: 500;
    padding: 0.5rem 1.5rem;
    border-radius: 0.5rem;
    transition: var(--transition);
}

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

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

/* Spinner */
.spinner {
    color: var(--primary);
    margin-bottom: 1rem;
}

/* Winners Section */
.winners-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.winners-header h4 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
}

.winner-item {
    animation: slideIn 0.3s ease forwards;
    opacity: 0;
    transform: translateY(10px);
}

@keyframes slideIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Hero Section */
.hero-image {
    padding: 3rem;
}

.hero-icon {
    font-size: 5rem;
    color: var(--primary);
    margin-bottom: 2rem;
    animation: float 3s ease-in-out infinite;
}

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

.hero-image h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.hero-image p {
    font-size: 1.1rem;
    color: #6c757d;
}

/* Features Section */
.section-features {
    padding: 5rem 0;
    background: white;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 3rem;
}

.feature-card {
    padding: 2rem;
    text-align: center;
    border-radius: 1rem;
    background: white;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    background: rgba(13, 110, 253, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon i {
    font-size: 32px;
    color: var(--primary);
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.feature-card p {
    color: #6c757d;
    margin: 0;
}

/* Steps Section */
.section-steps {
    padding: 5rem 0;
    background: #f8f9fa;
}

.step-card {
    padding: 2rem;
    text-align: center;
    background: white;
    border-radius: 1rem;
    box-shadow: var(--card-shadow);
    position: relative;
    transition: var(--transition);
}

.step-card:hover {
    transform: translateY(-5px);
}

.step-number {
    width: 32px;
    height: 32px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    position: absolute;
    top: 1rem;
    left: 1rem;
}

.step-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    background: rgba(13, 110, 253, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.step-icon i {
    font-size: 32px;
    color: var(--primary);
}

.step-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.step-card p {
    color: #6c757d;
    margin: 0;
}

/* Footer */
.footer {
    padding: 3rem 0;
    background: #212529;
    color: white;
}

.footer h5 {
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer p {
    color: rgba(255, 255, 255, 0.7);
    margin: 0;
}

.security-badges {
    display: flex;
    gap: 1rem;
}

.security-badges .badge {
    padding: 0.5rem 1rem;
    font-weight: 500;
}

/* Security Banner */
.security-banner {
    background: rgba(13, 110, 253, 0.02);
    border-bottom: 1px solid rgba(13, 110, 253, 0.1);
    padding: 0.5rem 0;
    margin-bottom: -56px;
}

.crypto-grid {
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.crypto-item {
    text-align: center;
}

.crypto-text {
    font-family: 'Courier New', monospace;
    font-weight: 700;
    color: var(--primary);
    font-size: 0.9rem;
    letter-spacing: 1px;
}

.crypto-item small {
    color: #6c757d;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Crypto Indicators */
.crypto-indicators {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.crypto-badge {
    background: rgba(13, 110, 253, 0.1);
    color: var(--primary);
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
}

.crypto-badge i {
    font-size: 0.875rem;
}

/* Crypto Animation */
.crypto-animation {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.crypto-char {
    font-family: 'Courier New', monospace;
    font-weight: 700;
    background: rgba(13, 110, 253, 0.1);
    color: var(--primary);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    font-size: 1rem;
    animation: cryptoFlicker 2s infinite;
}

@keyframes cryptoFlicker {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.crypto-char:nth-child(2) { animation-delay: 0.5s; }
.crypto-char:nth-child(3) { animation-delay: 1s; }
.crypto-char:nth-child(4) { animation-delay: 1.5s; }

/* Security Features */
.security-features {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 2rem;
}

.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.feature-item i {
    font-size: 1.5rem;
    color: var(--primary);
    background: rgba(13, 110, 253, 0.1);
    width: 3rem;
    height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: var(--transition);
}

.feature-item:hover i {
    transform: scale(1.1);
    background: rgba(13, 110, 253, 0.2);
}

.feature-item span {
    font-size: 0.875rem;
    font-weight: 500;
    color: #6c757d;
}

/* Security Section */
.security-section {
    padding: 5rem 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-top: 1px solid rgba(0, 0, 0, 0.05);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.crypto-stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-top: 3rem;
}

.stat-item {
    text-align: center;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
    font-family: 'Courier New', monospace;
}

.stat-label {
    font-size: 0.875rem;
    font-weight: 500;
    color: #6c757d;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Crypto Hash */
.crypto-hash {
    font-family: 'Courier New', monospace;
    letter-spacing: 1px;
}

/* Security Info */
.security-info {
    display: flex;
    align-items: center;
    color: #6c757d;
}

.security-info i {
    color: var(--success);
}

/* File Status Display */
.file-status {
    margin-top: 2rem;
    background: rgba(13, 110, 253, 0.03);
    border: 1px solid rgba(13, 110, 253, 0.1);
    border-radius: 1rem;
    padding: 1.5rem;
    transition: var(--transition);
}

.file-status-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid rgba(13, 110, 253, 0.1);
}

.file-status-header i {
    font-size: 1.5rem;
}

.file-status-header .filename {
    font-family: 'Courier New', monospace;
    font-weight: 600;
    color: var(--primary);
    flex-grow: 1;
}

.file-details {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: #6c757d;
}

.detail-item i {
    color: var(--primary);
}

.detail-item .participant-count {
    font-weight: 600;
    color: var(--primary);
}

.detail-item .file-hash {
    font-family: 'Courier New', monospace;
    font-size: 0.8rem;
}

.verification-progress {
    text-align: center;
}

.verification-progress .progress {
    height: 0.5rem;
    border-radius: 1rem;
    background: rgba(13, 110, 253, 0.1);
    margin-bottom: 0.5rem;
}

.verification-progress .progress-bar {
    background: var(--primary);
    border-radius: 1rem;
}

.verification-progress .status-text {
    color: var(--success);
    font-size: 0.8rem;
}

/* File Status Animation */
.file-status.show {
    animation: slideDown 0.3s ease forwards;
}

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

/* Responsive adjustments for file status */
@media (max-width: 768px) {
    .file-details {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }
    
    .file-status-header {
        flex-wrap: wrap;
        gap: 0.5rem;
    }
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    .crypto-grid {
        gap: 1rem;
    }

    .crypto-text {
        font-size: 0.8rem;
    }

    .crypto-stats {
        flex-direction: column;
        gap: 2rem;
    }

    .security-features {
        flex-wrap: wrap;
        gap: 1rem;
    }

    .feature-item {
        width: calc(50% - 0.5rem);
    }

    .main-section {
        padding: 3rem 0;
    }

    .hero-image {
        padding: 2rem;
        margin-top: 2rem;
    }

    .hero-image h2 {
        font-size: 2rem;
    }

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

    .feature-card,
    .step-card {
        margin-bottom: 1rem;
    }
}