:root {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #3d3d3d;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --accent: #4a90e2;
    --accent-hover: #357abd;
    --danger: #e74c3c;
    --success: #27ae60;
    --border: #404040;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    left: -280px;
    transition: left 0.3s ease;
    z-index: 1000;
    overflow-y: auto;
}

.sidebar.active {
    left: 0;
}

.sidebar-header {
    padding: 1.5rem 1rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background-color: var(--bg-primary);
}

.logo {
    font-size: 1.75rem;
    text-decoration: none;
    color: white;

}

.sidebar-nav {
    flex: 1;
    padding: 1rem 0;
    display: flex;
    flex-direction: column;
}

.nav-section {
    margin-bottom: 2rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    text-decoration: none;
    color: var(--text-primary);
    border: none;
    background: none;
    width: 100%;
    text-align: left;
    cursor: pointer;
    transition: background-color 0.2s;
    font-size: 0.875rem;
}

.nav-item:hover {
    background-color: var(--bg-tertiary);
}

.nav-item.active {
    background-color: var(--accent);
}

.nav-count {
    margin-left: auto;
    background-color: var(--bg-tertiary);
    padding: 0.25rem 0.5rem;
    border-radius: 12px;
    font-size: 0.75rem;
    min-width: 24px;
    text-align: center;
}

/* Main content */
.main-content {
    flex: 1;
    padding: 1rem;
    margin-left: 0;
    transition: margin-left 0.3s ease;
    width: 100%;
}

.main-content.sidebar-active {
    margin-left: 280px;
}

.header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 0.5rem 0;
}

.menu-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.menu-toggle:hover {
    background-color: var(--bg-secondary);
}

.page-title {
    font-size: 1.5rem;
    font-weight: 600;
}

/* Notes grid */
.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.note-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
}

.note-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.note-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.75rem;
}

.note-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
    flex: 1;
    font-size: 1.1rem;
    line-height: 1.3;
}

.note-menu {
    position: relative;
}

.menu-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 4px;
    transition: background-color 0.2s;
    font-size: 1.2rem;
    line-height: 1;
}

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

.dropdown-menu {
    position: absolute;
    right: 0;
    top: 100%;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 8px;
    min-width: 180px;
    z-index: 100;
    display: none;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
    padding: 0.5rem 0;
}

.dropdown-menu.show {
    display: block;
}

.dropdown-item {
    display: block;
    width: 100%;
    padding: 0.75rem 1rem;
    text-align: left;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    text-decoration: none;
    font-size: 0.875rem;
    transition: background-color 0.2s;
}

.dropdown-item:hover {
    background-color: var(--bg-secondary);
}

.dropdown-item.danger {
    color: var(--danger);
}

.note-category {
    color: var(--accent);
    font-size: 0.875rem;
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.note-date {
    color: var(--text-secondary);
    font-size: 0.75rem;
    margin-bottom: 1rem;
}

.note-preview {
    color: var(--text-secondary);
    font-size: 0.875rem;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.2s;
    justify-content: center;
}

.btn-primary {
    background-color: var(--accent);
    color: white;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
}

.btn-danger {
    background-color: var(--danger);
    color: white;
}

.btn-danger:hover {
    background-color: #c0392b;
    transform: translateY(-1px);
}

.btn-success {
    background-color: var(--success);
    color: white;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.875rem;
}

.form-input {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: border-color 0.2s;
}

.form-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(74, 144, 226, 0.2);
}

/* Login */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--bg-primary);
    padding: 1rem;
}

.login-form {
    background-color: var(--bg-secondary);
    padding: 2.5rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    width: 100%;
    max-width: 400px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}

.login-title {
    text-align: center;
    margin-bottom: 2rem;
    font-size: 2rem;
    font-weight: 700;
}

.error {
    color: var(--danger);
    text-align: center;
    margin-bottom: 1rem;
    padding: 0.75rem;
    background-color: rgba(231, 76, 60, 0.1);
    border-radius: 6px;
    font-size: 0.875rem;
}

/* Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 999;
    display: none;
    backdrop-filter: blur(2px);
}

.overlay.active {
    display: block;
}

/* Note content view */
.note-content {
    background-color: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    line-height: 1.7;
    font-size: 1.05rem;
}

.note-content ul,
.note-content ol {
    padding-left: 2rem;
    margin: 1rem 0;
}

.note-content p {
    margin: 1rem 0;
}

.note-content strong {
    font-weight: 600;
}

.note-content em {
    font-style: italic;
}

/* Responsive */
@media (max-width: 768px) {
    .notes-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .sidebar {
        width: 100%;
        left: -100%;
    }
    
    .main-content.sidebar-active {
        margin-left: 0;
    }
    
    .header {
        margin-bottom: 1.5rem;
    }
    
    .page-title {
        font-size: 1.25rem;
    }
    
    .note-card {
        padding: 1.25rem;
    }
    
    .login-form {
        padding: 2rem 1.5rem;
    }
}

@media (min-width: 769px) {
    .sidebar {
        position: static;
        height: auto;
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .menu-toggle {
        display: none;
    }
    
    .overlay {
        display: none !important;
    }
}

@media (min-width: 1200px) {
    .notes-grid {
        grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    }
}

/* Utility classes */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

/* Scrollbar */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--bg-tertiary);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}