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

:root {
    --bg: #f5f7fa;
    --card-bg: #ffffff;
    --text: #1a1a2e;
    --text-secondary: #555;
    --accent: #1677ff;
    --accent-hover: #0958d9;
    --border: #e0e0e0;
    --shadow: 0 8px 24px rgba(0,0,0,0.08);
    --radius: 16px;
    --header-bg: #ffffff;
    --footer-bg: #1a1a2e;
    --footer-text: #ccc;
}

[data-theme="dark"] {
    --bg: #0d1117;
    --card-bg: #161b22;
    --text: #e6edf3;
    --text-secondary: #8b949e;
    --accent: #58a6ff;
    --accent-hover: #79c0ff;
    --border: #30363d;
    --shadow: 0 8px 24px rgba(0,0,0,0.4);
    --header-bg: #161b22;
    --footer-bg: #0d1117;
    --footer-text: #8b949e;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

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

/* Header */
header {
    background: var(--header-bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 0;
}

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    background: linear-gradient(135deg, #1677ff, #00b4d8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 25px;
}

nav a {
    text-decoration: none;
    color: var(--text);
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover {
    color: var(--accent);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--text);
    border-radius: 2px;
    transition: 0.3s;
}

#themeToggle {
    background: none;
    border: 2px solid var(--border);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: 0.3s;
}

#themeToggle:hover {
    border-color: var(--accent);
}

/* Hero */
.hero {
    background: linear-gradient(135deg, #1677ff, #00b4d8);
    color: white;
    padding: 60px 0;
    text-align: center;
    border-radius: 0 0 30px 30px;
    margin-bottom: 40px;
}

.hero h2 {
    font-size: 2.5rem;
    margin-bottom: 15px;
    font-weight: 800;
}

.hero p {
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto 20px;
    opacity: 0.9;
}

.featured-badge {
    display: inline-block;
    background: rgba(255,255,255,0.2);
    padding: 8px 20px;
    border-radius: 30px;
    font-weight: 600;
}

/* Filters */
.filter-form {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    align-items: center;
    margin-bottom: 30px;
}

.search-box {
    display: flex;
    flex: 1;
    min-width: 200px;
}

.search-box input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid var(--border);
    border-radius: var(--radius) 0 0 var(--radius);
    background: var(--card-bg);
    color: var(--text);
    font-size: 1rem;
}

.search-box button {
    padding: 12px 20px;
    border: 2px solid var(--accent);
    border-left: none;
    border-radius: 0 var(--radius) var(--radius) 0;
    background: var(--accent);
    color: white;
    cursor: pointer;
    font-size: 1rem;
}

select {
    padding: 12px 16px;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    background: var(--card-bg);
    color: var(--text);
    font-size: 1rem;
    cursor: pointer;
}

/* App Grid */
.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 25px;
    margin-bottom: 40px;
}

.app-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 25px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: transform 0.3s, box-shadow 0.3s;
}

.app-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 32px rgba(0,0,0,0.12);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.card-header h3 {
    font-size: 1.3rem;
    font-weight: 700;
}

.category-tag {
    background: var(--accent);
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.description {
    color: var(--text-secondary);
    margin-bottom: 15px;
    font-size: 0.95rem;
}

.rating {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 15px;
    flex-wrap: wrap;
}

.stars {
    font-size: 1rem;
}

.rating-value {
    font-weight: 700;
    color: var(--accent);
}

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

.card-actions {
    margin-bottom: 15px;
}

.download-btn {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 12px 28px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 700;
    transition: background 0.3s, transform 0.2s;
    border: none;
    cursor: pointer;
}

.download-btn:hover {
    background: var(--accent-hover);
    transform: scale(1.05);
}

.reviews {
    border-top: 1px solid var(--border);
    padding-top: 15px;
    margin-top: 10px;
}

.reviews h4 {
    margin-bottom: 10px;
    font-size: 1rem;
}

.review-item {
    margin-bottom: 10px;
    padding: 10px;
    background: var(--bg);
    border-radius: 8px;
}

.review-item strong {
    display: block;
    margin-bottom: 4px;
}

/* History */
.history {
    margin-bottom: 40px;
}

.history h3 {
    margin-bottom: 15px;
}

.history-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.history-list li {
    background: var(--card-bg);
    padding: 8px 16px;
    border-radius: 20px;
    border: 1px solid var(--border);
    font-size: 0.9rem;
}

/* Footer */
footer {
    background: var(--footer-bg);
    color: var(--footer-text);
    padding: 30px 0;
    text-align: center;
}

footer a {
    color: var(--accent);
    text-decoration: none;
}

/* Admin */
.admin-login {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.login-container {
    background: var(--card-bg);
    padding: 40px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 400px;
}

.login-container h2 {
    text-align: center;
    margin-bottom: 25px;
}

.login-container input {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 2px solid var(--border);
    border-radius: 8px;
    background: var(--bg);
    color: var(--text);
}

.login-container button {
    width: 100%;
    padding: 12px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
}

.error {
    color: #e74c3c;
    margin-bottom: 15px;
}

.success {
    color: #2ecc71;
    margin-bottom: 15px;
}

.admin-page table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

.admin-page th, .admin-page td {
    border: 1px solid var(--border);
    padding: 10px;
    text-align: left;
}

.admin-page input, .admin-page textarea {
    width: 100%;
    padding: 8px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--bg);
    color: var(--text);
}

.admin-page button {
    padding: 12px 24px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--header-bg);
        border-bottom: 1px solid var(--border);
        padding: 20px;
        gap: 15px;
    }
    .nav-links.active {
        display: flex;
    }
    .hamburger {
        display: flex;
    }
    .hero h2 {
        font-size: 1.8rem;
    }
    .app-grid {
        grid-template-columns: 1fr;
    }
    .filter-form {
        flex-direction: column;
    }
}