[hidden] {
    display: none !important;
}

:root {
    color-scheme: light dark;
    
    --primary-color: light-dark(#007bff, #3d8bfd);
    --primary-hover: light-dark(#0056b3, #5299fd);
    --success-color: light-dark(#28a745, #198754);
    --success-hover: light-dark(#218838, #157347);
    
    --bg-color: light-dark(#f8f9fa, #1a1a1a);
    --card-bg: light-dark(#ffffff, #2a2a2a);
    --text-color: light-dark(#333, #e0e0e0);
    --text-muted: light-dark(#6c757d, #a0a0a0);
    --title-color: light-dark(#222, #ffffff);
    --label-color: light-dark(#444, #bbbbbb);
    
    --border-color: light-dark(#dee2e6, #444);
    --input-focus: light-dark(#80bdff, #0056b3);
    --shadow: light-dark(0 4px 6px rgba(0, 0, 0, 0.1), 0 4px 6px rgba(0, 0, 0, 0.4));
    --radius: 12px;

    /* Semantic colors for alerts/notifications */
    --success-bg: light-dark(#d4edda, #1c2f23);
    --success-text: light-dark(#155724, #a5d6a7);
    --warning-bg: light-dark(#fff3cd, #2e2a1a);
    --warning-text: light-dark(#856404, #ffe082);
    --error-bg: light-dark(#f8d7da, #33191c);
    --error-text: light-dark(#721c24, #ef9a9a);
}

body {
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    line-height: 1.5;
}

.container {
    max-width: 900px;
    margin: 40px auto;
    padding: 0 20px;
}

header {
    margin-top: 20px;
    margin-bottom: 30px;
    text-align: center;
    position: relative;
}

.user-menu {
    position: absolute;
    top: 0;
    right: 20px;
    display: flex;
    gap: 15px;
    align-items: center;
    font-size: 0.9rem;
}

.user-menu a {
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 600;
}

.user-menu .logout-link {
    color: var(--error-text);
    background: var(--error-bg);
    padding: 5px 10px;
    border-radius: 6px;
}

.user-menu .logout-link:hover {
    filter: brightness(0.9);
}

h1 {
    font-weight: 700;
    font-size: 2rem;
    color: var(--title-color);
    margin: 0;
}

.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 30px;
    margin-bottom: 30px;
}

table {
    width: 100%;
    border-collapse: collapse;
}

table td {
    padding: 12px 8px;
    vertical-align: middle;
}

label {
    font-weight: 600;
    color: var(--label-color);
}

/* Forms and Inputs */
input[type="text"],
input[type="number"],
input[type="password"],
select,
textarea {
    width: 100%;
    padding: 10px 14px;
    background-color: var(--card-bg);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.2s, box-shadow 0.2s;
    box-sizing: border-box;
}

input[type="text"]:focus,
input[type="number"]:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--input-focus);
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.25);
}

input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

small {
    display: block;
    margin-top: 4px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.button-group {
    margin-top: 30px;
    display: flex;
    gap: 15px;
    justify-content: flex-end;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.btn {
    padding: 12px 24px;
    font-size: 1rem;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn-calc {
    background-color: var(--primary-color);
    color: #ffffff;
}

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

.btn-save {
    background-color: var(--success-color);
    color: #ffffff;
}

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

.btn:active {
    transform: translateY(0);
}

/* Results Area */
.results-area {
    margin-top: 20px;
}

.results-area h2, .results-area h3 {
    margin-top: 0;
    color: var(--title-color);
}

/* Notifications */
.notifications-area {
    margin: 20px 0;
}

.notification {
    padding: 16px;
    margin-bottom: 12px;
    border-radius: 8px;
    font-weight: 500;
    border-left: 5px solid transparent;
}

.notification-success {
    background-color: var(--success-bg);
    color: var(--success-text);
    border-left-color: var(--success-color);
}

.notification-warning {
    background-color: var(--warning-bg);
    color: var(--warning-text);
    border-left-color: #ffc107;
}

.notification-error {
    background-color: var(--error-bg);
    color: var(--error-text);
    border-left-color: #dc3545;
}

/* Alerts */
.alert {
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    border: 1px solid transparent;
}

.alert-warning {
    background-color: var(--warning-bg);
    color: var(--warning-text);
    border-color: var(--border-color);
}

.alert h3 {
    margin: 0 0 10px 0;
    font-size: 1.1rem;
    color: inherit;
}

.alert ul {
    margin: 10px 0;
    padding-left: 20px;
}

/* HR styling in descriptions */
hr {
    border: 0;
    height: 1px;
    background: var(--border-color);
    margin: 25px 0;
}