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

:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --secondary-color: #6b7280;
    --danger-color: #ef4444;
    --success-color: #10b981;
    --background: #0f172a;
    --card-background: #1e293b;
    --card-hover: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --input-background: #0f172a;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
}

[data-theme="light"] {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #6b7280;
    --danger-color: #dc2626;
    --success-color: #16a34a;
    --background: #f3f4f6;
    --card-background: #ffffff;
    --card-hover: #f9fafb;
    --text-primary: #111827;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --input-background: #ffffff;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 15px;
}

/* Theme Toggle */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.theme-toggle:hover {
    transform: scale(1.1);
    background-color: var(--card-hover);
}

.theme-toggle svg {
    width: 24px;
    height: 24px;
    fill: var(--text-primary);
}

/* Login Styles */
.login-container {
    background: var(--card-background);
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    padding: 30px;
    width: 100%;
    max-width: 400px;
    border: 1px solid var(--border-color);
}

.login-header {
    text-align: center;
    margin-bottom: 25px;
}

.login-header h1 {
    color: var(--primary-color);
    font-size: 24px;
    margin-bottom: 8px;
}

.login-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    color: var(--text-primary);
    font-size: 14px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    transition: all 0.2s;
    background-color: var(--input-background);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.btn {
    padding: 10px 18px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    -webkit-tap-highlight-color: transparent;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    width: 100%;
}

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

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

.btn-secondary:hover {
    background-color: #4b5563;
    transform: translateY(-1px);
}

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

.btn-danger:hover {
    background-color: #dc2626;
    transform: translateY(-1px);
}

.btn-success {
    background-color: var(--success-color);
    color: white;
    width: 100%;
}

.btn-success:hover {
    background-color: #059669;
    transform: translateY(-1px);
}

.btn-logout {
    background-color: transparent;
    color: var(--danger-color);
    border: 1px solid var(--danger-color);
    padding: 8px 16px;
}

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

.error-message {
    margin-top: 15px;
    padding: 10px;
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
    border-radius: 8px;
    font-size: 14px;
    display: none;
    border: 1px solid rgba(239, 68, 68, 0.3);
}

.config-info {
    margin-top: 20px;
    padding: 15px;
    background-color: var(--card-hover);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.config-info p {
    font-size: 13px;
    color: var(--text-secondary);
    margin: 0;
}

/* Dashboard Styles */
.dashboard-container {
    min-height: 100vh;
    background-color: var(--background);
}

.dashboard-header {
    background-color: var(--card-background);
    box-shadow: var(--shadow);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
}

.header-content h1 {
    color: var(--primary-color);
    font-size: 20px;
    margin: 0;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.header-divider {
    width: 1px;
    height: 24px;
    background-color: var(--border-color);
    margin: 0 8px;
}

#welcomeUser {
    color: var(--text-secondary);
    font-size: 13px;
}

/* Header Buttons */
.btn-header {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 8px 14px;
    border-radius: 8px;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s;
    cursor: pointer;
}

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

.btn-header svg {
    flex-shrink: 0;
}

.btn-add {
    background-color: var(--primary-color);
    color: white;
    border: none;
}

.btn-add:hover {
    background-color: var(--primary-hover);
}

.btn-export, .btn-import {
    color: var(--text-secondary);
}

.btn-export:hover, .btn-import:hover {
    color: var(--text-primary);
    border-color: var(--primary-color);
}

.dashboard-main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px 15px;
}

.controls-section {
    background-color: var(--card-background);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.search-bar {
    position: relative;
}

.search-icon {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    pointer-events: none;
}

.search-input {
    width: 100%;
    padding: 12px 16px 12px 48px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    background-color: var(--input-background);
    color: var(--text-primary);
    transition: all 0.2s;
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.action-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.contacts-section {
    background-color: var(--card-background);
    border-radius: 12px;
    padding: 20px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.contacts-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border-color);
}

.contacts-header h2 {
    font-size: 18px;
    color: var(--text-primary);
}

.contacts-count {
    background-color: var(--background);
    color: var(--text-secondary);
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 13px;
}

.contacts-list {
    display: grid;
    gap: 12px;
}

.contact-card {
    background-color: var(--background);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.2s;
    flex-wrap: wrap;
    gap: 12px;
}

.contact-card:hover {
    box-shadow: var(--shadow);
    transform: translateY(-2px);
    background-color: var(--card-hover);
}

.contact-info {
    flex: 1;
    min-width: 200px;
}

.contact-name {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
    font-size: 15px;
}

.contact-id {
    color: var(--text-secondary);
    font-size: 13px;
    font-family: monospace;
}

.contact-notes {
    color: var(--text-secondary);
    font-size: 12px;
    margin-top: 4px;
    font-style: italic;
}

.contact-actions {
    display: flex;
    gap: 8px;
    align-items: center;
    justify-content: flex-end;
}

.btn-icon {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    background-color: var(--card-background);
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s;
    text-decoration: none;
    color: var(--text-primary);
    white-space: nowrap;
}

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

.btn-connect {
    background-color: var(--primary-color);
    color: white;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    white-space: nowrap;
    flex-shrink: 0;
}

.btn-connect:hover {
    background-color: var(--primary-hover);
}

.btn-connect svg {
    flex-shrink: 0;
}

/* Dropdown Menu */
.dropdown {
    position: relative;
}

.btn-menu {
    background-color: transparent;
    border: none;
    border-radius: 6px;
    padding: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    color: var(--text-secondary);
}

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

.btn-menu svg {
    width: 20px;
    height: 20px;
}

.dropdown-menu {
    position: absolute;
    right: 0;
    top: 100%;
    margin-top: 4px;
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    min-width: 150px;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.2s;
}

.dropdown-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 100%;
    padding: 10px 14px;
    border: none;
    background: none;
    color: var(--text-primary);
    font-size: 13px;
    cursor: pointer;
    transition: all 0.2s;
    text-align: left;
}

.dropdown-item:first-child {
    border-radius: 8px 8px 0 0;
}

.dropdown-item:last-child {
    border-radius: 0 0 8px 8px;
}

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

.dropdown-item svg {
    flex-shrink: 0;
    width: 16px;
    height: 16px;
}

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

.dropdown-item-danger:hover {
    background-color: rgba(239, 68, 68, 0.1);
}

.dropdown-item.disabled {
    opacity: 0.5;
    cursor: not-allowed;
    color: var(--text-secondary);
}

.read-only-notice {
    background-color: var(--card-hover);
    color: var(--text-secondary);
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 12px;
    display: flex;
    align-items: center;
    gap: 4px;
}

.empty-state {
    text-align: center;
    padding: 50px 20px;
    color: var(--text-secondary);
}

.empty-state p:first-child {
    font-size: 16px;
    margin-bottom: 8px;
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    animation: fadeIn 0.2s;
    padding: 15px;
    overflow-y: auto;
}

.modal.show {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background-color: var(--card-background);
    border-radius: 12px;
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    animation: slideIn 0.3s;
    border: 1px solid var(--border-color);
}

.modal-small {
    max-width: 400px;
}

.modal-header {
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    font-size: 18px;
    color: var(--text-primary);
}

.modal-close {
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-secondary);
    cursor: pointer;
    line-height: 1;
    padding: 0;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    transition: all 0.2s;
}

.modal-close:hover {
    color: var(--text-primary);
    background-color: var(--background);
}

.modal-body {
    padding: 20px;
}

.contact-form {
    padding: 20px;
}

.modal-actions {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: 20px;
}

.delete-contact-name {
    font-weight: 600;
    color: var(--danger-color);
    margin-top: 10px;
    word-break: break-all;
}

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

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

/* Mobile Responsive */
@media (max-width: 768px) {
    .header-content {
        padding: 0 10px;
    }
    
    .header-left {
        flex: 1;
    }
    
    .header-content h1 {
        font-size: 16px;
    }
    
    #welcomeUser {
        display: none;
    }
    
    .btn-text {
        display: none;
    }
    
    .btn-header {
        padding: 8px 10px;
    }
    
    .header-divider {
        margin: 0 4px;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 10px;
    }
    
    .login-container {
        padding: 20px;
        margin: 10px;
    }
    
    .login-header h1 {
        font-size: 22px;
    }
    
    .dashboard-header {
        padding: 10px 0;
    }
    
    
    .dashboard-main {
        padding: 15px 10px;
    }
    
    .controls-section,
    .contacts-section {
        padding: 15px;
        border-radius: 10px;
    }
    
    
    .contacts-header {
        flex-direction: column;
        gap: 10px;
        align-items: flex-start;
    }
    
    .contact-card {
        flex-direction: column;
        align-items: flex-start;
        padding: 12px;
    }
    
    .contact-info {
        width: 100%;
    }
    
    .contact-actions {
        width: 100%;
        display: flex;
        justify-content: space-between;
        align-items: center;
        gap: 8px;
    }
    
    .btn-connect {
        flex: none;
        max-width: calc(100% - 40px);
    }
    
    .dropdown-menu {
        right: 0;
        left: auto;
    }
    
    .modal-content {
        margin: 10px;
        max-height: calc(100vh - 30px);
    }
    
    .modal-header {
        padding: 15px;
    }
    
    .modal-header h2 {
        font-size: 16px;
    }
    
    .contact-form,
    .modal-body {
        padding: 15px;
    }
    
    .modal-actions {
        flex-direction: column-reverse;
    }
    
    .modal-actions .btn {
        width: 100%;
    }
    
    .theme-toggle {
        top: 10px;
        right: 10px;
        width: 40px;
        height: 40px;
    }
    
    .theme-toggle svg {
        width: 20px;
        height: 20px;
    }
}

@media (max-width: 375px) {
    .login-header h1 {
        font-size: 20px;
    }
    
    .btn {
        font-size: 13px;
        padding: 10px 14px;
    }
    
    .btn-connect {
        font-size: 13px;
        padding: 8px 12px;
    }
    
    .contact-name {
        font-size: 14px;
    }
    
    .contact-id {
        font-size: 12px;
    }
}

/* Touch-friendly improvements */
@media (hover: none) {
    .btn:active {
        transform: scale(0.98);
    }
    
    .contact-card:active {
        transform: scale(0.99);
    }
    
    .btn-icon:active {
        transform: scale(0.95);
    }
}