/* Reset and base */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: #f8fafc;
    color: #1e293b;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a {
    color: inherit;
    text-decoration: none;
}
ul { list-style: none; }
img { max-width: 100%; display: block; }
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 12px;
    font-weight: 600;
    font-size: 15px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s ease;
}
.btn-primary {
    background: #6366f1;
    color: #fff;
    border-color: #6366f1;
    box-shadow: 0 4px 14px rgba(99,102,241,0.3);
}
.btn-primary:hover {
    background: #4f46e5;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99,102,241,0.4);
}
.btn-outline {
    background: transparent;
    color: #6366f1;
    border-color: #6366f1;
}
.btn-outline:hover {
    background: #eef2ff;
    transform: translateY(-2px);
}
.btn-download svg {
    animation: bounce 2s infinite;
}
@keyframes bounce {
    0%,100% { transform: translateY(0); }
    50% { transform: translateY(-4px); }
}

/* Header */
.site-header {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 100;
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 22px;
    font-weight: 700;
    color: #1e293b;
}
.logo svg { flex-shrink: 0; }
.main-nav ul {
    display: flex;
    gap: 8px;
}
.main-nav a {
    padding: 8px 16px;
    border-radius: 8px;
    font-weight: 500;
    transition: background 0.2s;
}
.main-nav a:hover {
    background: #eef2ff;
    color: #6366f1;
}
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}
.hamburger span {
    width: 28px;
    height: 3px;
    background: #1e293b;
    border-radius: 2px;
    transition: 0.3s;
}

/* Hero */
.hero {
    padding: 80px 0 60px;
    background: linear-gradient(135deg, #eef2ff 0%, #f8fafc 100%);
}
.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}
.hero h1 {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
    background: linear-gradient(135deg, #6366f1, #a855f7);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero-subtitle {
    font-size: 1.1rem;
    color: #475569;
    margin-bottom: 32px;
}
.hero-buttons {
    display: flex;
    gap: 16px;
    align-items: center;
    flex-wrap: wrap;
}
.qr-code-wrapper {
    position: relative;
}
.qr-popup {
    display: none;
    position: absolute;
    top: 120%;
    left: 50%;
    transform: translateX(-50%);
    background: #fff;
    border-radius: 16px;
    padding: 20px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
    text-align: center;
    z-index: 50;
    width: 200px;
}
.qr-popup.active {
    display: block;
}
.qr-popup img {
    margin: 0 auto 12px;
    border-radius: 8px;
}
.qr-popup p {
    font-size: 13px;
    color: #64748b;
}
.hero-visual {
    display: flex;
    justify-content: center;
}
.hero-card {
    background: #fff;
    border-radius: 24px;
    padding: 40px 32px;
    text-align: center;
    box-shadow: 0 20px 60px rgba(99,102,241,0.1);
    border: 1px solid #e2e8f0;
}
.hero-card p {
    font-size: 18px;
    font-weight: 600;
    margin: 16px 0 8px;
}
.hero-card span {
    color: #6366f1;
    font-weight: 700;
    font-size: 14px;
    background: #eef2ff;
    padding: 4px 12px;
    border-radius: 20px;
}

/* Section */
.section {
    padding: 60px 0;
}
.section-title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: #0f172a;
}

/* Version */
.version-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 2fr;
    gap: 20px;
}
.version-card {
    background: #fff;
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.04);
    border: 1px solid #e2e8f0;
    transition: transform 0.3s, box-shadow 0.3s;
}
.version-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0,0,0,0.08);
}
.version-card h3 {
    font-size: 16px;
    color: #64748b;
    margin-bottom: 12px;
}
.version-number {
    font-size: 2rem;
    font-weight: 800;
    color: #6366f1;
}
.version-date {
    color: #94a3b8;
    font-size: 14px;
    margin-top: 4px;
}
.version-card ul {
    padding-left: 0;
}
.version-card li {
    padding: 4px 0;
    color: #475569;
    font-size: 14px;
}
.version-card li::before {
    content: "• ";
    color: #6366f1;
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}
.feature-card {
    background: #fff;
    border-radius: 20px;
    padding: 28px 24px;
    text-align: center;
    box-shadow: 0 4px 16px rgba(0,0,0,0.04);
    border: 1px solid #e2e8f0;
    transition: all 0.3s ease;
}
.feature-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(99,102,241,0.1);
    border-color: #c7d2fe;
}
.feature-icon {
    font-size: 3rem;
    margin-bottom: 16px;
}
.feature-card h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}
.feature-card p {
    font-size: 14px;
    color: #64748b;
}

/* Reviews */
.rating-summary {
    text-align: center;
    margin-bottom: 32px;
}
.rating-stars {
    display: inline-flex;
    gap: 4px;
    margin-bottom: 8px;
}
.rating-text {
    font-size: 16px;
    color: #475569;
}
.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}
.review-card {
    background: #fff;
    border-radius: 16px;
    padding: 20px 24px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.04);
    border: 1px solid #e2e8f0;
}
.review-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}
.review-header strong {
    font-weight: 600;
}
.review-date {
    font-size: 13px;
    color: #94a3b8;
}
.review-card p {
    color: #475569;
    font-size: 14px;
}

/* Recommend */
.recommend-card {
    background: linear-gradient(135deg, #eef2ff, #f3e8ff);
    border-radius: 24px;
    padding: 48px 40px;
    text-align: center;
    border: 1px solid #c7d2fe;
}
.recommend-card h2 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: #1e293b;
}
.recommend-card p {
    color: #475569;
    margin-bottom: 24px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

/* Footer */
.site-footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 40px 0;
    text-align: center;
}
.footer-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 20px;
}
.footer-links a {
    color: #cbd5e1;
    transition: color 0.2s;
}
.footer-links a:hover {
    color: #fff;
}
.footer-copy {
    font-size: 14px;
}
.footer-copy a {
    color: #818cf8;
}

/* Admin Login */
.admin-login-page {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: #f1f5f9;
}
.login-container {
    background: #fff;
    border-radius: 24px;
    padding: 48px 40px;
    width: 100%;
    max-width: 420px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.08);
}
.login-container h1 {
    text-align: center;
    margin-bottom: 32px;
    font-size: 24px;
}
.error-msg {
    background: #fef2f2;
    color: #dc2626;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 16px;
    font-size: 14px;
}
.form-group {
    margin-bottom: 16px;
}
.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 6px;
    color: #475569;
}
.form-group input, .form-group textarea, .form-group select {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    font-size: 14px;
    font-family: inherit;
    transition: border-color 0.2s;
}
.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: #6366f1;
    box-shadow: 0 0 0 3px rgba(99,102,241,0.1);
}
.login-footer {
    text-align: center;
    margin-top: 16px;
    font-size: 14px;
}
.login-footer a {
    color: #6366f1;
}

/* Admin Dashboard */
.admin-dashboard {
    background: #f8fafc;
}
.admin-header {
    background: #fff;
    padding: 20px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 100;
}
.admin-header h1 {
    font-size: 20px;
}
.admin-actions {
    display: flex;
    gap: 8px;
}
.admin-main {
    max-width: 900px;
    margin: 40px auto;
    padding: 0 20px;
}
.success-msg {
    background: #f0fdf4;
    color: #16a34a;
    padding: 12px 20px;
    border-radius: 10px;
    margin-bottom: 20px;
}
.admin-form fieldset {
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    padding: 24px;
    margin-bottom: 24px;
    background: #fff;
}
.admin-form legend {
    font-weight: 600;
    font-size: 16px;
    padding: 0 8px;
    color: #0f172a;
}
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}
.feature-item, .review-item {
    display: flex;
    gap: 8px;
    align-items: center;
    margin-bottom: 8px;
    flex-wrap: wrap;
}
.feature-item input, .review-item input {
    flex: 1;
    min-width: 120px;
    padding: 8px 12px;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
}
.btn-remove {
    background: #fef2f2;
    color: #dc2626;
    border: none;
    padding: 8px 16px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 13px;
    transition: background 0.2s;
}
.btn-remove:hover {
    background: #fee2e2;
}

/* Responsive */
@media (max-width: 768px) {
    .main-nav {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: #fff;
        border-bottom: 1px solid #e2e8f0;
        padding: 16px 20px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    }
    .main-nav.active {
        display: block;
    }
    .main-nav ul {
        flex-direction: column;
    }
    .hamburger {
        display: flex;
    }
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero h1 {
        font-size: 2rem;
    }
    .hero-buttons {
        justify-content: center;
    }
    .version-grid {
        grid-template-columns: 1fr;
    }
    .form-row {
        grid-template-columns: 1fr;
    }
    .section-title {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 40px 0;
    }
    .hero h1 {
        font-size: 1.6rem;
    }
    .btn {
        padding: 10px 20px;
        font-size: 14px;
    }
    .feature-item, .review-item {
        flex-direction: column;
    }
    .feature-item input, .review-item input {
        width: 100%;
    }
}