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

body {
    font-family: 'Segoe UI', 'Hiragino Sans', 'Yu Gothic', sans-serif;
    line-height: 1.8;
    color: #333;
    background: linear-gradient(135deg, #f5f7fa 0%, #e8f0f8 100%);
}

header {
    background: #fff;
    padding: 1.5rem 2rem;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 1rem;
    position: relative;
}

.logo {
    font-size: 1.5rem;
    font-weight: 600;
    color: #2c5aa0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.patent-badge {
    font-size: 0.65rem;
    background: #e3f2fd;
    color: #2c5aa0;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-weight: 600;
}

.hamburger-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
}

.hamburger-menu {
    width: 40px;
    height: 40px;
    background: white;
    border: 2px solid #2c5aa0;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    padding: 8px;
    transition: all 0.3s;
    position: relative;
    z-index: 1001;
    margin-left: -0.45cm;
}

.patent-notice {
    font-size: 0.65rem;
    font-weight: 600;
    color: #1565c0;
    background: #b3d9ff;
    padding: 0.3rem 0.6rem;
    border-radius: 4px;
    text-align: center;
    line-height: 1.3;
    white-space: nowrap;
    margin-left: -1rem;
}

.hamburger-menu:hover {
    background: #f0f4f8;
}

.hamburger-menu span {
    display: block;
    width: 20px;
    height: 2px;
    background: #2c5aa0;
    transition: all 0.3s;
}

.hamburger-menu.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger-menu.active span:nth-child(2) {
    opacity: 0;
}

.hamburger-menu.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

.dropdown-menu {
    position: absolute;
    top: 50px;
    left: 0;
    background: white;
    border: 2px solid #2c5aa0;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    display: none;
    flex-direction: column;
    min-width: 180px;
    overflow: hidden;
    z-index: 1000;
}

.dropdown-menu.active {
    display: flex;
}

.dropdown-menu a {
    padding: 1rem 1.5rem;
    color: #2c5aa0;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    border-bottom: 1px solid #e3f2fd;
}

.dropdown-menu a:last-child {
    border-bottom: none;
}

.dropdown-menu a:hover {
    background: #f0f4f8;
    padding-left: 2rem;
}

.nav-buttons button {
    margin-left: 1rem;
    padding: 0.6rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-login {
    background: transparent;
    color: #2c5aa0;
    border: 1px solid #2c5aa0;
}

.btn-login:hover {
    background: #f0f4f8;
}

.btn-signup {
    background: #2c5aa0;
    color: white;
}

.btn-signup:hover {
    background: #234a85;
}

.hero {
    max-width: 1200px;
    margin: 0 auto;
    padding: 5rem 2rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.book-decoration {
    position: absolute;
    opacity: 0.35;
    pointer-events: none;
}

.book-decoration.book1 {
    top: 50px;
    right: 100px;
    width: 180px;
    height: 220px;
    background: linear-gradient(to right, white 0%, white 15%, #c62828 15%, #e53935 100%);
    border-radius: 8px;
    box-shadow: 5px 5px 20px rgba(0, 0, 0, 0.3);
    animation: float 6s ease-in-out infinite;
    transform: rotate(-15deg);
    border: 2px solid #b71c1c;
}

.book-decoration.book2 {
    bottom: 80px;
    left: 80px;
    width: 160px;
    height: 200px;
    background: linear-gradient(to right, white 0%, white 15%, #1565c0 15%, #1976d2 100%);
    border-radius: 8px;
    box-shadow: -5px 5px 20px rgba(0, 0, 0, 0.3);
    animation: float 8s ease-in-out infinite reverse;
    transform: rotate(12deg);
    border: 2px solid #0d47a1;
}

.book-decoration.book3 {
    top: 200px;
    left: 150px;
    width: 140px;
    height: 180px;
    background: linear-gradient(to right, white 0%, white 15%, #2e7d32 15%, #388e3c 100%);
    border-radius: 6px;
    box-shadow: 3px 3px 15px rgba(0, 0, 0, 0.25);
    animation: float 7s ease-in-out infinite;
    transform: rotate(-8deg);
    border: 2px solid #1b5e20;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(-15deg); }
    50% { transform: translateY(-25px) rotate(-12deg); }
}

.hero h1 {
    font-size: 2.8rem;
    margin-bottom: 1.5rem;
    color: #1a1a1a;
    font-weight: 600;
    position: relative;
    z-index: 1;
}

.hero p {
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 2.5rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    position: relative;
    z-index: 1;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn-primary {
    padding: 1rem 2.5rem;
    background: #2c5aa0;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-primary:hover {
    background: #234a85;
    transform: translateY(-2px);
}

.btn-secondary {
    padding: 1rem 2.5rem;
    background: white;
    color: #2c5aa0;
    border: 2px solid #2c5aa0;
    border-radius: 8px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-secondary:hover {
    background: #f0f4f8;
}

.features {
    background: #f8f9fa;
    padding: 5rem 2rem;
}

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

.section-title {
    text-align: center;
    font-size: 2.2rem;
    margin-bottom: 3rem;
    color: #1a1a1a;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
}

.feature-card {
    background: white;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.06);
    transition: transform 0.3s;
}

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

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.feature-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.feature-card p {
    color: #666;
    line-height: 1.8;
}

.how-it-works {
    max-width: 1200px;
    margin: 0 auto;
    padding: 5rem 2rem;
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.step {
    text-align: center;
    padding: 2rem;
}

.step-number {
    display: inline-block;
    width: 50px;
    height: 50px;
    background: #2c5aa0;
    color: white;
    border-radius: 50%;
    line-height: 50px;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.step h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.step p {
    color: #666;
}

.pricing {
    background: #f8f9fa;
    padding: 5rem 2rem;
}

.pricing-container {
    max-width: 1000px;
    margin: 0 auto;
}

.pricing-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.pricing-card {
    background: white;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.06);
    text-align: center;
}

.pricing-card.featured {
    border: 3px solid #2c5aa0;
    position: relative;
}

.badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: #2c5aa0;
    color: white;
    padding: 0.3rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
}

.pricing-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.price {
    font-size: 2.5rem;
    font-weight: 600;
    color: #2c5aa0;
    margin: 1.5rem 0;
}

.price span {
    font-size: 1rem;
    color: #666;
    font-weight: 400;
}

.features-list {
    list-style: none;
    margin: 2rem 0;
    text-align: left;
}

.features-list li {
    padding: 0.6rem 0;
    color: #666;
}

.features-list li:before {
    content: "✓ ";
    color: #2c5aa0;
    font-weight: 600;
    margin-right: 0.5rem;
}

.cta {
    background: linear-gradient(135deg, #2c5aa0 0%, #1a3d6d 100%);
    color: white;
    padding: 5rem 2rem;
    text-align: center;
}

.cta h2 {
    font-size: 2.2rem;
    margin-bottom: 1.5rem;
}

.cta p {
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    opacity: 0.9;
}

.cta button {
    padding: 1rem 3rem;
    background: white;
    color: #2c5aa0;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.cta button:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

footer {
    background: #1a1a1a;
    color: white;
    padding: 3rem 2rem;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s;
}

.footer-links a:hover {
    opacity: 1;
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

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

    .section-title {
        font-size: 1.8rem;
    }

    .nav-buttons button {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
    }
}