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

:root {
    --background: #fff;
    --background-alt: #f9f9f9;
    --container-bg: #fff;
    --header-bg: #fff;
    --primary: #667eea;
    --primary-dark: #764ba2;
    --text: #111;
    --text-light: #333;
    --nav-link: #666;
    --nav-link-hover: #f0f0f0;
    --table-header: #667eea;
    --table-header-border: #5568d3;
    --table-row-hover: #f8f9ff;
    --input-border: #e0e0e0;
    --input-focus: #667eea;
    --button-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --button-gradient-alt: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
    --delete-btn: #f44336;
    --delete-btn-hover: #da190b;
    --success-bg: #d4edda;
    --success-text: #155724;
    --success-border: #c3e6cb;
    --error-bg: #f8d7da;
    --error-text: #721c24;
    --error-border: #f5c6cb;
}

body.darkmode, body.darkmode :root {
    --background: #181a1b;
    --background-alt: #23272b;
    --container-bg: #23272b;
    --header-bg: #23272b;
    --primary: #3399ff;
    --primary-dark: #1a2a3a;
    --text: #eee;
    --text-light: #bbb;
    --nav-link: #bbb;
    --nav-link-hover: #222;
    --table-header: #222e3a;
    --table-header-border: #3399ff;
    --table-row-hover: #23272b;
    --input-border: #444;
    --input-focus: #3399ff;
    --button-gradient: linear-gradient(135deg, #3399ff 0%, #1a2a3a 100%);
    --button-gradient-alt: linear-gradient(135deg, #388e3c 0%, #1b5e20 100%);
    --delete-btn: #b71c1c;
    --delete-btn-hover: #7f0000;
    --success-bg: #234d2c;
    --success-text: #b9f6ca;
    --success-border: #388e3c;
    --error-bg: #4a2323;
    --error-text: #ff8a80;
    --error-border: #b71c1c;
}

@media (prefers-color-scheme: dark) {
    :root {
        --background: #181a1b;
        --background-alt: #23272b;
        --container-bg: #23272b;
        --header-bg: #23272b;
        --primary: #3399ff;
        --primary-dark: #1a2a3a;
        --text: #eee;
        --text-light: #bbb;
        --nav-link: #bbb;
        --nav-link-hover: #222;
        --table-header: #222e3a;
        --table-header-border: #3399ff;
        --table-row-hover: #23272b;
        --input-border: #444;
        --input-focus: #3399ff;
        --button-gradient: linear-gradient(135deg, #3399ff 0%, #1a2a3a 100%);
        --button-gradient-alt: linear-gradient(135deg, #388e3c 0%, #1b5e20 100%);
        --delete-btn: #b71c1c;
        --delete-btn-hover: #7f0000;
        --success-bg: #234d2c;
        --success-text: #b9f6ca;
        --success-border: #388e3c;
        --error-bg: #4a2323;
        --error-text: #ff8a80;
        --error-border: #b71c1c;
    }
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--background);
    min-height: 100vh;
    padding-top: 80px;
    color: var(--text);
}

/* Header Styles */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--header-bg);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-light);
}

.nav {
    display: flex;
    gap: 5px;
}

.nav-link {
    padding: 10px 20px;
    text-decoration: none;
    color: var(--nav-link);
    border-radius: 6px;
    transition: all 0.3s;
    font-weight: 500;
}

.nav-link:hover {
    background-color: var(--nav-link-hover);
    color: var(--text-light);
}

.nav-link.active {
    background: var(--button-gradient);
    color: #fff;
}

/* Container */
.container {
    max-width: 1400px;
    margin: 30px auto;
    padding: 30px;
    background-color: var(--container-bg);
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

h1 {
    color: var(--text-light);
    text-align: center;
    margin-bottom: 30px;
    font-size: 28px;
}

h2 {
    color: var(--text-light);
    margin-bottom: 20px;
    font-size: 20px;
    border-bottom: 2px solid var(--primary);
    padding-bottom: 10px;
}

/* Table Styles */
.table-wrapper {
    overflow-x: auto;
    margin-bottom: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
    background-color: var(--container-bg);
}

th {
    background-color: var(--table-header);
    color: #fff;
    padding: 15px;
    text-align: left;
    font-weight: 600;
    border: 1px solid var(--table-header-border);
}

td {
    border: 1px solid var(--input-border);
    padding: 12px;
}

tr:hover {
    background-color: var(--table-row-hover);
}

.text-input {
    width: 100%;
    padding: 8px 12px;
    border: 2px solid var(--input-border);
    border-radius: 6px;
    box-sizing: border-box;
    font-size: 14px;
    transition: border-color 0.3s;
}

.text-input:focus {
    outline: none;
    border-color: var(--input-focus);
}

/* Toggle Switch */
.switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 24px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 24px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 3px;
    bottom: 3px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: #4CAF50;
}

input:focus + .slider {
    box-shadow: 0 0 1px #4CAF50;
}

input:checked + .slider:before {
    transform: translateX(26px);
}

/* Buttons */
.button-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 20px;
}

.save-btn, .add-btn {
    padding: 14px 30px;
    background: var(--button-gradient);
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
}

.save-btn:hover, .add-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.save-btn:active, .add-btn:active {
    transform: translateY(0);
}

.add-btn {
    background: var(--button-gradient-alt);
}

.delete-btn {
    padding: 8px 12px;
    background-color: var(--delete-btn);
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}

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

/* Messages */
.message {
    text-align: center;
    padding: 12px;
    margin: 20px 0;
    border-radius: 8px;
    display: none;
    font-weight: 500;
}

.message.success {
    background-color: var(--success-bg);
    color: var(--success-text);
    border: 1px solid var(--success-border);
    display: block;
}

.message.error {
    background-color: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
    display: block;
}

/* Settings Page */
.settings-section {
    margin-bottom: 40px;
    padding: 20px;
    background-color: var(--background-alt);
    border-radius: 8px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-light);
    font-weight: 500;
}

.form-group .text-input {
    max-width: 600px;
}

/* Responsive */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 15px;
    }
    
    .nav {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .container {
        padding: 15px;
        margin: 15px;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .save-btn, .add-btn {
        width: 100%;
    }
}