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

body {
    font-family: 'Arial', sans-serif;
    background: linear-gradient(135deg, #0f172a, #1e3a8a);
    color: #fff;
    line-height: 1.6;
    padding: 20px;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.header {
    width: 100%;
    text-align: center;
    padding: 15px 0;
    margin-bottom: 10px;
}

.header h1 {
    font-size: 2.2rem;
    margin-bottom: 5px;
    color: #b9e9f0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #fff;
    text-decoration: none;
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 30px;
    transition: all 0.3s ease;
}

.back-link:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.toc-container {
    position: fixed;
    left: 20px;
    top: 120px;
    width: 300px;
    max-height: calc(100vh - 140px);
    overflow-y: auto;
    background: linear-gradient(135deg, rgba(15, 23, 42, 0.95), rgba(30, 58, 138, 0.9));
    backdrop-filter: blur(20px);
    border-radius: 20px;
    padding: 25px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4), 
                0 0 0 1px rgba(255, 255, 255, 0.1),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
    z-index: 100;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.toc-container::-webkit-scrollbar {
    width: 6px;
}

.toc-container::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 3px;
}

.toc-container::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, #4ecdc4, #44a08d);
    border-radius: 3px;
}

.toc-container::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, #5eead4, #4ecdc4);
}

.toc-container.hidden {
    transform: translateX(-110%);
    opacity: 0;
}

.toc-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid;
    border-image: linear-gradient(90deg, #4ecdc4, transparent) 1;
}

.toc-title {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, #4ecdc4, #44a08d);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: 0.5px;
}

.toc-toggle {
    background: linear-gradient(135deg, rgba(78, 205, 196, 0.2), rgba(68, 160, 141, 0.2));
    border: 1px solid rgba(78, 205, 196, 0.3);
    color: #4ecdc4;
    font-size: 1.1rem;
    cursor: pointer;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.toc-toggle:hover {
    background: linear-gradient(135deg, rgba(78, 205, 196, 0.3), rgba(68, 160, 141, 0.3));
    transform: scale(1.1);
    box-shadow: 0 4px 15px rgba(78, 205, 196, 0.3);
}

.toc-toggle.collapsed {
    transform: rotate(-90deg);
}

.toc-list {
    list-style: none;
    padding-left: 0;
    transition: all 0.3s ease;
}

.toc-list.collapsed {
    display: none;
}

.toc-list li {
    margin-bottom: 3px;
}

.toc-parent {
    position: relative;
}

.toc-expand {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    font-size: 0.65rem;
    color: #4ecdc4;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    user-select: none;
    border-radius: 5px;
    background: rgba(78, 205, 196, 0.1);
}

.toc-expand:hover {
    background: rgba(78, 205, 196, 0.2);
    transform: scale(1.15);
}

.toc-expand.expanded {
    transform: rotate(90deg);
    background: rgba(78, 205, 196, 0.2);
}

.toc-parent > a {
    display: inline-flex;
    align-items: center;
    color: rgba(255, 255, 255, 0.95);
    text-decoration: none;
    padding: 10px 14px;
    border-radius: 10px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    width: calc(100% - 26px);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    overflow: hidden;
}

.toc-parent > a::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 3px;
    background: linear-gradient(180deg, #4ecdc4, #44a08d);
    transform: scaleY(0);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.toc-parent > a:hover {
    background: linear-gradient(90deg, rgba(78, 205, 196, 0.15), transparent);
    color: #fff;
    transform: translateX(5px);
    box-shadow: 0 2px 10px rgba(78, 205, 196, 0.1);
}

.toc-parent > a:hover::before {
    transform: scaleY(1);
}

.toc-list .toc-sublist {
    display: none;
    padding-left: 28px;
    margin-top: 4px;
    margin-bottom: 4px;
    border-left: 2px solid rgba(78, 205, 196, 0.2);
    animation: slideDown 0.3s ease;
}

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

.toc-list .toc-sublist.active {
    display: block;
}

.toc-list .toc-sublist li {
    margin-bottom: 2px;
    list-style: none;
}

.toc-list .toc-sublist a {
    font-size: 0.88rem;
    color: rgba(255, 255, 255, 0.75);
    text-decoration: none;
    display: block;
    padding: 8px 12px;
    border-radius: 8px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    font-weight: 400;
}

.toc-list .toc-sublist a::before {
    content: '';
    position: absolute;
    left: 6px;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 4px;
    background: #4ecdc4;
    border-radius: 50%;
    opacity: 0.5;
    transition: all 0.3s ease;
}

.toc-list .toc-sublist a:hover {
    background: linear-gradient(90deg, rgba(78, 205, 196, 0.12), transparent);
    color: #fff;
    transform: translateX(4px);
    padding-left: 16px;
}

.toc-list .toc-sublist a:hover::before {
    opacity: 1;
    transform: translateY(-50%) scale(1.3);
    box-shadow: 0 0 8px rgba(78, 205, 196, 0.6);
}

.content-wrapper {
    margin-left: 320px;
    min-width: 300px;
    width: calc(100% - 340px);
}

.content-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 22px;
    box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    border: 1px solid rgba(255, 255, 255, 0.18);
    margin-bottom: 22px;
}

.section {
    margin-bottom: 30px;
}

.section h2 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: #ffa502;
    border-bottom: 2px solid rgba(255, 255, 255, 0.2);
    padding-bottom: 10px;
}

.section h3 {
    font-size: 1.4rem;
    margin: 20px 0 15px;
    color: #4ecdc4;
}

.section p {
    margin-bottom: 10px;
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.9);
    line-height: 1.65;
}

.section ul, .section ol {
    padding-left: 30px;
    margin-bottom: 20px;
}

.section li {
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.9);
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 15px 0 25px;
    background: rgba(255, 255, 255, 0.05);
}

table, th, td {
    border: 1px solid rgba(255, 255, 255, 0.2);
}

th, td {
    padding: 12px;
    text-align: left;
}

th {
    background-color: rgba(255, 165, 2, 0.2);
    color: #ffa502;
}

.contact-box {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    padding: 20px;
    margin-top: 20px;
}

.contact-box h3 {
    color: #4ecdc4;
    margin-bottom: 15px;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    margin: 0 10px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    border: none;
    border-radius: 30px;
    font-size: 1.1rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.btn.email {
    background: linear-gradient(45deg, #ff6b6b, #ffa502);
}

@media (max-width: 1024px) {
    .toc-container {
        position: static;
        width: 100%;
        max-height: none;
        margin-bottom: 25px;
    }

    .content-wrapper {
        margin-left: 0;
        width: 100%;
    }

    .toc-container {
        width: 100%;
    }
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
        padding: 10px;
    }

    .header h1 {
        font-size: 2rem;
    }

    .content-card {
        padding: 20px;
    }

    .toc-container {
        width: 100%;
    }
}

footer {
    text-align: center;
    padding: 30px;
    opacity: 0.6;
    font-size: 0.95rem;
    color: #94a3b8;
    margin-top: 20px;
}

.floating-home-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, #60a5fa, #3b82f6);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    box-shadow: 0 4px 15px rgba(96, 165, 250, 0.4);
    transition: all 0.3s ease;
    z-index: 1000;
}

.floating-home-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(96, 165, 250, 0.6);
    background: linear-gradient(135deg, #3b82f6, #2563eb);
}

.floating-home-btn:active {
    transform: translateY(-1px);
}

@media (max-width: 768px) {
    .floating-home-btn {
        width: 50px;
        height: 50px;
        bottom: 20px;
        right: 20px;
    }
}

html {
    scroll-behavior: smooth;
}