:root {
    --bg-main: #f3f4f6;
    --bg-sidebar: #ffffff;
    --bg-card: #ffffff;
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --accent-primary: #0BC07D;
    --accent-secondary: #089A64;
    --border-color: #e5e7eb;
    --hover-bg: #f9fafb;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Scrollbar customization */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-main);
}
::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

.app-container {
    display: flex;
    width: 100%;
    height: 100%;
}

/* Sidebar */
.sidebar {
    width: 300px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    z-index: 10;
    box-shadow: 4px 0 15px rgba(0, 0, 0, 0.05);
}

.logo-container {
    padding: 24px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-bottom: 1px solid var(--border-color);
}

.logo-icon {
    background: #ffffff;
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    color: white;
    box-shadow: 0 4px 10px rgba(11, 192, 125, 0.3);
    overflow: hidden;
}

.logo-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.logo-text {
    font-size: 1.2rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    color: var(--text-primary);
}

.logo-text span {
    color: var(--accent-primary);
    font-weight: 400;
    margin-left: 5px;
}

.sidebar-nav {
    flex: 1;
    overflow-y: auto;
    padding: 16px 12px;
}

.home-btn {
    padding: 12px 16px;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.95rem;
    margin-bottom: 12px;
    transition: all 0.2s ease;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
}

.home-btn:hover {
    background: var(--hover-bg);
    border-color: var(--accent-primary);
}

.home-btn i {
    color: var(--accent-primary);
    font-size: 1.1rem;
}

#menu-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

/* Accordion Categories */
.category-item {
    margin-bottom: 8px;
}

.category-header {
    padding: 12px 16px;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.95rem;
    background-color: var(--bg-sidebar);
    border: 1px solid transparent;
    transition: all 0.3s ease;
}

.category-header:hover {
    background-color: var(--hover-bg);
}

.category-header.active {
    background-color: var(--hover-bg);
    border-color: var(--border-color);
}

.category-header .arrow {
    margin-left: auto;
    font-size: 0.8rem;
    transition: transform 0.3s ease;
    color: var(--text-secondary);
}

.category-header.active .arrow {
    transform: rotate(180deg);
}

.category-header i:first-child {
    color: var(--accent-primary);
    width: 20px;
    text-align: center;
}

.submenu {
    display: none;
    list-style: none;
    flex-direction: column;
    gap: 4px;
    padding-left: 10px;
    margin-top: 4px;
}

.category-item.open .submenu {
    display: flex;
}

.menu-item {
    padding: 10px 16px;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-secondary);
    transition: all 0.2s ease;
    font-weight: 500;
    font-size: 0.9rem;
    position: relative;
    border-left: 3px solid transparent;
}

.menu-item:hover {
    color: var(--text-primary);
    background-color: var(--hover-bg);
}

.menu-item.active {
    background: linear-gradient(90deg, rgba(11, 192, 125, 0.1) 0%, transparent 100%);
    color: var(--accent-primary);
    border-left: 3px solid var(--accent-primary);
}

.menu-item i {
    width: 20px;
    text-align: center;
    font-size: 1.1rem;
}

.sidebar-footer {
    padding: 20px 24px;
    border-top: 1px solid var(--border-color);
    background-color: var(--hover-bg);
    display: flex;
    justify-content: center;
}

.contact-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--accent-primary);
    color: white;
    text-decoration: none;
    padding: 12px 16px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    width: 100%;
    box-shadow: 0 4px 6px rgba(11, 192, 125, 0.2);
}

.contact-btn:hover {
    background: var(--accent-secondary);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(11, 192, 125, 0.3);
}

.contact-btn i {
    font-size: 1.1rem;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--bg-main);
    overflow: hidden;
}

body.dark-mode {
    --bg-main: #111827;
    --bg-sidebar: #1f2937;
    --bg-card: #1f2937;
    --text-primary: #f9fafb;
    --text-secondary: #9ca3af;
    --border-color: #374151;
    --hover-bg: #374151;
}

.topbar {
    padding: 24px 40px;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--bg-card);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.02);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.topbar-left, .topbar-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.icon-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 8px;
    border-radius: 8px;
    transition: all 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
}

.icon-btn:hover {
    background-color: var(--hover-bg);
    color: var(--text-primary);
}

.icon-btn.active {
    color: var(--warning);
}

.hidden {
    display: none !important;
}

.copy-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 6px 12px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.copy-btn:hover {
    background: var(--hover-bg);
    color: var(--text-primary);
    border-color: var(--text-secondary);
}

.copy-btn.copied {
    color: var(--success);
    border-color: var(--success);
    background: rgba(16, 185, 129, 0.1);
}

.section-header-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.search-box {
    position: relative;
    width: 300px;
}

.search-box i {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
}

.search-box input {
    width: 100%;
    padding: 10px 10px 10px 36px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 0.95rem;
    outline: none;
    transition: all 0.3s ease;
}

.search-box input:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(11, 192, 125, 0.1);
}

.topbar h2 {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
}

.content-area {
    flex: 1;
    padding: 40px;
    overflow-y: auto;
    position: relative;
}

/* Welcome Screen */
.welcome-screen {
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: var(--text-secondary);
    animation: fadeIn 1s ease;
}

.welcome-icon {
    font-size: 4rem;
    margin-bottom: 20px;
    color: var(--border-color);
}

.welcome-screen h3 {
    color: var(--text-primary);
    font-size: 1.5rem;
    margin-bottom: 10px;
}

.welcome-screen p {
    max-width: 400px;
    line-height: 1.6;
}

/* Subject Content Styles */
.subject-content {
    animation: slideUp 0.4s ease forwards;
    max-width: 900px;
    margin: 0 auto;
}

.section-block {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 24px;
    margin-bottom: 24px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.02);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.section-block:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.05);
}

.section-title {
    font-size: 1.2rem;
    color: var(--accent-primary);
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-title i {
    font-size: 1.1rem;
}

.step-list {
    list-style: none;
    counter-reset: custom-counter;
}

.step-item {
    position: relative;
    padding-left: 40px;
    margin-bottom: 20px;
    line-height: 1.6;
    color: var(--text-primary);
}

.step-item:last-child {
    margin-bottom: 0;
}

.step-item::before {
    counter-increment: custom-counter;
    content: counter(custom-counter);
    position: absolute;
    left: 0;
    top: 0;
    width: 28px;
    height: 28px;
    background: var(--accent-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: 600;
    font-size: 0.85rem;
    box-shadow: 0 4px 10px rgba(11, 192, 125, 0.3);
}

.info-text {
    margin-bottom: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-card);
    padding: 16px;
    border-left: 4px solid var(--accent-secondary);
    border-radius: 0 8px 8px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.02);
}

.link-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--hover-bg);
    border-radius: 8px;
    margin-bottom: 12px;
    text-decoration: none;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.link-item:hover {
    background: #ffffff;
    border-color: var(--accent-primary);
    box-shadow: 0 4px 6px rgba(11, 192, 125, 0.1);
}

.link-item i {
    color: var(--accent-primary);
    font-size: 1.2rem;
}

.link-text {
    flex: 1;
    font-weight: 500;
}

.link-url {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}