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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --android-color: #3ddc84;
    --ios-color: #147efb;
    --background: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --success: #10b981;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

/* Header */
header {
    background: var(--card-bg);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo i {
    font-size: 2rem;
    color: var(--primary-color);
}

.logo h1 {
    font-size: 1.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 1.5rem;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    font-weight: 500;
}

nav a:hover {
    color: var(--text-primary);
    background: rgba(99, 102, 241, 0.1);
}

nav a.active {
    color: var(--primary-color);
    background: rgba(99, 102, 241, 0.2);
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 0 2rem;
}

.hero h2 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--text-primary), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

/* Upload Section */
.upload-section {
    margin: 2rem 0;
}

.upload-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s ease;
}

.upload-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    cursor: pointer;
    user-select: none;
}

.upload-header:hover {
    background: rgba(99, 102, 241, 0.05);
}

.upload-header h3 {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.2rem;
    color: var(--text-primary);
}

.upload-header i {
    color: var(--primary-color);
}

.toggle-upload-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0.5rem;
    transition: all 0.3s ease;
}

.toggle-upload-btn:hover {
    color: var(--primary-color);
    transform: scale(1.1);
}

.toggle-upload-btn.active {
    transform: rotate(180deg);
}

.upload-form {
    padding: 0 1.5rem 1.5rem;
    animation: slideDown 0.3s ease;
}

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

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
}

.form-group label i {
    color: var(--primary-color);
}

.form-group input[type="password"] {
    width: 100%;
    padding: 0.9rem;
    background: var(--background);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.form-group input[type="password"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.file-input-wrapper {
    position: relative;
}

.file-input-wrapper input[type="file"] {
    position: absolute;
    opacity: 0;
    width: 100%;
    height: 100%;
    cursor: pointer;
    z-index: 2;
}

.file-input-display {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 2rem;
    background: var(--background);
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.file-input-display:hover {
    border-color: var(--primary-color);
    background: rgba(99, 102, 241, 0.05);
}

.file-input-display i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.file-input-display span {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.file-input-display.has-file {
    border-style: solid;
    border-color: var(--success);
    background: rgba(16, 185, 129, 0.05);
}

.file-input-display.has-file i {
    color: var(--success);
}

.upload-submit-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
}

.upload-submit-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.upload-submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.upload-progress {
    margin-top: 1rem;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--background);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    display: block;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.upload-message {
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 8px;
    display: none;
}

.upload-message.success {
    display: block;
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--success);
    color: var(--success);
}

.upload-message.error {
    display: block;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid #ef4444;
    color: #ef4444;
}

/* Search Section */
.search-section {
    margin: 2rem 0;
}

.search-bar {
    position: relative;
    max-width: 600px;
    margin: 0 auto;
}

.search-bar i {
    position: absolute;
    left: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.search-bar input {
    width: 100%;
    padding: 1rem 1.5rem 1rem 3.5rem;
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.3s ease;
}

.search-bar input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* Stats Section */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.stat-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.stat-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.stat-card h3 {
    font-size: 2rem;
    color: var(--text-primary);
}

.stat-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Apps Grid */
main {
    flex: 1;
    padding: 2rem 0;
}

.apps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.app-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.app-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.app-card:hover::before {
    transform: scaleX(1);
}

.app-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.app-icon {
    width: 80px;
    height: 80px;
    border-radius: 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
}

.app-icon i {
    color: white;
}

.app-card.android .app-icon {
    background: linear-gradient(135deg, #3ddc84, #00c853);
}

.app-card.ios .app-icon {
    background: linear-gradient(135deg, #147efb, #0a66c2);
}

.app-info h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.app-meta {
    display: flex;
    gap: 1rem;
    margin: 1rem 0;
    flex-wrap: wrap;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

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

.platform-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.4rem 0.8rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-top: 0.5rem;
}

.platform-badge.android {
    background: rgba(61, 220, 132, 0.15);
    color: var(--android-color);
}

.platform-badge.ios {
    background: rgba(20, 126, 251, 0.15);
    color: var(--ios-color);
}

.download-btn {
    width: 100%;
    margin-top: 1rem;
    padding: 0.9rem;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
}

.download-btn:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--secondary-color));
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.download-btn:active {
    transform: translateY(0);
}

.delete-btn {
    width: 100%;
    margin-top: 0.5rem;
    padding: 0.9rem;
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
}

.delete-btn:hover {
    background: linear-gradient(135deg, #dc2626, #b91c1c);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.4);
}

.delete-btn:active {
    transform: translateY(0);
}

.app-actions {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 1rem;
}

/* No Results */
.no-results {
    text-align: center;
    padding: 4rem 2rem;
}

.no-results i {
    font-size: 4rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.no-results h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.no-results p {
    color: var(--text-secondary);
}

/* Footer */
footer {
    background: var(--card-bg);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    text-align: center;
    color: var(--text-secondary);
    margin-top: auto;
}

/* Responsive Design */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        gap: 0.5rem;
    }

    nav a {
        padding: 0.4rem 0.8rem;
        font-size: 0.9rem;
    }

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

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

    .apps-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.2rem;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

    .search-bar input {
        padding: 0.8rem 1rem 0.8rem 3rem;
    }
}

/* Loading Animation */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.loading {
    animation: pulse 1.5s ease-in-out infinite;
}