:root {
  --font-family-sans-serif: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-size-base: 1rem;
  --line-height-base: 1.6;
  --border-radius-base: 6px;
  
  --color-bg-light: #f1f5f9;
  --color-surface-light: #ffffff;
  --color-text-primary-light: #1e293b;
  --color-text-secondary-light: #64748b;
  --color-border-light: #cbd5e1;
  
  --color-primary-bg-light: #0ea5e9;
  --color-primary-text-light: #ffffff;
  --color-primary-hover-bg-light: #0284c7;
  --color-primary-focus-ring-light-rgb: 14, 165, 233;

  --color-input-bg-light: #ffffff;
  --color-table-header-bg-light: #f8fafc;
  --color-table-row-hover-bg-light: #f1f5f9;

  --color-success-bg-light: #f0fdf4;
  --color-success-text-light: #15803d;
  --color-success-border-light: #bbf7d0;

  --color-danger-bg-light: #fef2f2;
  --color-danger-text-light: #b91c1c;
  --color-danger-border-light: #fecaca;

  --color-bg-dark: #0f172a;
  --color-surface-dark: #1e293b;
  --color-text-primary-dark: #e2e8f0;
  --color-text-secondary-dark: #94a3b8;
  --color-border-dark: #334155;
  
  --color-primary-bg-dark: #38bdf8;
  --color-primary-text-dark: #0f172a;
  --color-primary-hover-bg-dark: #0ea5e9;
  --color-primary-focus-ring-dark-rgb: 56, 189, 248;

  --color-input-bg-dark: #334155;
  --color-table-header-bg-dark: #334155;
  --color-table-row-hover-bg-dark: #283344;
  
  --color-success-bg-dark: #052e16;
  --color-success-text-dark: #4ade80;
  --color-success-border-dark: #15803d;

  --color-danger-bg-dark: #450a0a;
  --color-danger-text-dark: #f87171;
  --color-danger-border-dark: #b91c1c;
  
  --shadow-soft-light: 0 2px 5px rgba(0, 0, 0, 0.06);
  --shadow-medium-light: 0 4px 10px rgba(0, 0, 0, 0.08);
  --shadow-soft-dark: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-medium-dark: 0 4px 12px rgba(0, 0, 0, 0.3);

  --color-bg: var(--color-bg-light);
  --color-surface: var(--color-surface-light);
  --color-text-primary: var(--color-text-primary-light);
  --color-text-secondary: var(--color-text-secondary-light);
  --color-border: var(--color-border-light);
  --color-primary-bg: var(--color-primary-bg-light);
  --color-primary-text: var(--color-primary-text-light);
  --color-primary-hover-bg: var(--color-primary-hover-bg-light);
  --color-primary-focus-ring-rgb: var(--color-primary-focus-ring-light-rgb);
  --color-input-bg: var(--color-input-bg-light);
  --color-table-header-bg: var(--color-table-header-bg-light);
  --color-table-row-hover-bg: var(--color-table-row-hover-bg-light);
  --color-success-bg: var(--color-success-bg-light);
  --color-success-text: var(--color-success-text-light);
  --color-success-border: var(--color-success-border-light);
  --color-danger-bg: var(--color-danger-bg-light);
  --color-danger-text: var(--color-danger-text-light);
  --color-danger-border: var(--color-danger-border-light);
  --current-shadow-soft: var(--shadow-soft-light);
  --current-shadow-medium: var(--shadow-medium-light);
}

html.dark-mode {
  --color-bg: var(--color-bg-dark);
  --color-surface: var(--color-surface-dark);
  --color-text-primary: var(--color-text-primary-dark);
  --color-text-secondary: var(--color-text-secondary-dark);
  --color-border: var(--color-border-dark);
  --color-primary-bg: var(--color-primary-bg-dark);
  --color-primary-text: var(--color-primary-text-dark);
  --color-primary-hover-bg: var(--color-primary-hover-bg-dark);
  --color-primary-focus-ring-rgb: var(--color-primary-focus-ring-dark-rgb);
  --color-input-bg: var(--color-input-bg-dark);
  --color-table-header-bg: var(--color-table-header-bg-dark);
  --color-table-row-hover-bg: var(--color-table-row-hover-bg-dark);
  --color-success-bg: var(--color-success-bg-dark);
  --color-success-text: var(--color-success-text-dark);
  --color-success-border: var(--color-success-border-dark);
  --color-danger-bg: var(--color-danger-bg-dark);
  --color-danger-text: var(--color-danger-text-dark);
  --color-danger-border: var(--color-danger-border-dark);
  --current-shadow-soft: var(--shadow-soft-dark);
  --current-shadow-medium: var(--shadow-medium-dark);
}

body {
  font-family: var(--font-family-sans-serif);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  margin: 0;
  padding: 0;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Layout */
.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 1.5rem;
  box-sizing: border-box;
}

/* Navbar */
.navbar {
  background-color: var(--color-surface);
  color: var(--color-text-primary);
  padding: 0.75rem 1.5rem;
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--current-shadow-soft);
  display: flex;
  justify-content: space-between; /* For brand and links/toggle */
  align-items: center;
  flex-wrap: wrap;
  transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
}

.navbar-brand {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text-primary);
  text-decoration: none;
}

.navbar-brand:hover {
  color: var(--color-primary-bg);
}

.navbar-toggle {
  background: none;
  border: none;
  color: var(--color-text-primary);
  font-size: 1.75rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  display: none;
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 0;
}

.navbar-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-weight: 500;
  padding: 0.5rem 0.75rem;
  border-radius: var(--border-radius-base);
  transition: color 0.2s ease-in-out, background-color 0.2s ease-in-out;
}

.navbar-links a:hover,
.navbar-links a.active-link {
  color: var(--color-primary-bg);
}
html:not(.dark-mode) .navbar-links a:hover,
html:not(.dark-mode) .navbar-links a.active-link {
  background-color: rgba(52, 73, 94, 0.05); /* Lighter primary bg for light mode hover */
}
html.dark-mode .navbar-links a:hover,
html.dark-mode .navbar-links a.active-link {
  background-color: rgba(66, 153, 225, 0.1); /* Lighter primary bg for dark mode hover */
}


/* Forms */
form {
  padding: 0;
}

.form-wrapper {
  max-width: 480px;
  margin: 2rem auto;
  padding: 2rem;
  background: var(--color-surface);
  border-radius: var(--border-radius-base);
  box-shadow: var(--current-shadow-medium);
  box-sizing: border-box;
  transition: background-color 0.3s ease;
}

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

input[type="text"],
input[type="date"],
input[type="password"],
input[type="number"],
input[type="email"] {
  width: 100%;
  padding: 0.75rem;
  margin-bottom: 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-base);
  font-size: var(--font-size-base);
  box-sizing: border-box;
  background-color: var(--color-input-bg);
  color: var(--color-text-primary);
  transition: border-color 0.2s ease-in-out, box-shadow 0.2s ease-in-out, background-color 0.3s ease, color 0.3s ease;
}

input[type="text"]:focus,
input[type="date"]:focus,
input[type="password"]:focus,
input[type="number"]:focus,
input[type="email"]:focus {
  outline: none;
  border-color: var(--color-primary-bg);
}
html:not(.dark-mode) input[type="text"]:focus,
html:not(.dark-mode) input[type="date"]:focus,
html:not(.dark-mode) input[type="password"]:focus,
html:not(.dark-mode) input[type="number"]:focus,
html:not(.dark-mode) input[type="email"]:focus {
  box-shadow: 0 0 0 2px rgba(52, 73, 94, 0.2); /* Light mode focus ring */
}
html.dark-mode input[type="text"]:focus,
html.dark-mode input[type="date"]:focus,
html.dark-mode input[type="password"]:focus,
html.dark-mode input[type="number"]:focus,
html.dark-mode input[type="email"]:focus {
  box-shadow: 0 0 0 2px rgba(66, 153, 225, 0.3); /* Dark mode focus ring */
}


button,
input[type="submit"] {
  background-color: var(--color-primary-bg);
  color: var(--color-primary-text);
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--border-radius-base);
  cursor: pointer;
  font-size: var(--font-size-base);
  font-weight: 500;
  transition: background-color 0.2s ease-in-out;
  display: inline-block;
  text-align: center;
}

button:hover,
input[type="submit"]:hover {
  background-color: var(--color-primary-hover-bg);
}

/* Flash Messages */
.flash-messages {
  max-width: 1140px;
  margin: 1rem auto 0;
  padding: 0 1.5rem;
}

.flash-message {
  padding: 1rem;
  border-radius: var(--border-radius-base);
  margin-bottom: 1rem;
  border: 1px solid transparent;
  font-weight: 500;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.flash-message.success {
  background-color: var(--color-success-bg);
  color: var(--color-success-text);
  border-color: var(--color-success-border);
}

.flash-message.danger {
  background-color: var(--color-danger-bg);
  color: var(--color-danger-text);
  border-color: var(--color-danger-border);
}

/* Calendar base style (already present) */
#calendar {
  background: var(--color-surface);
  padding: 1.5rem;
  border-radius: var(--border-radius-base);
  box-shadow: var(--current-shadow-medium);
  flex: 1;
  transition: background-color 0.3s ease;
}
/* FullCalendar specific dark mode overrides */
html.dark-mode #calendar {
    /* General FullCalendar variables */
    --fc-border-color: var(--color-border-dark);
    --fc-page-bg-color: var(--color-surface-dark); /* Should match #calendar background */
    --fc-neutral-bg-color: rgba(255, 255, 255, 0.05); /* For elements like day headers */
    --fc-list-event-hover-bg-color: rgba(255, 255, 255, 0.08);
    
    /* Day cell backgrounds */
    --fc-daygrid-day-bg-color: transparent; /* Make day cells transparent to show main calendar surface */
    /* Today's date highlight */
    --fc-day-today-bg-color: rgba(var(--color-primary-bg-rgb-dark, 66, 153, 225), 0.2); /* Use dark primary with alpha */
    
    /* Text colors for calendar chrome */
    --fc-col-header-cell-cushion-color: var(--color-text-secondary-dark); /* Day names (Mon, Tue) */
    --fc-daygrid-day-number-color: var(--color-text-secondary-dark); /* Date numbers */
    --fc-list-day-text-color: var(--color-text-primary-dark);
    --fc-list-day-side-text-color: var(--color-text-secondary-dark);

    /* Toolbar (header with title and prev/next buttons) */
    --fc-toolbar-title-color: var(--color-text-primary-dark);
    --fc-button-text-color: var(--color-text-primary-dark);
    --fc-button-bg-color: var(--color-surface-dark); /* Or slightly different like var(--color-bg-dark) */
    --fc-button-border-color: var(--color-border-dark);
    --fc-button-hover-bg-color: rgba(255, 255, 255, 0.08);
    --fc-button-hover-border-color: var(--color-border-dark);
    --fc-button-active-bg-color: rgba(255, 255, 255, 0.12);
    --fc-button-active-border-color: var(--color-border-dark);
    --fc-button-disabled-bg-color: rgba(var(--color-text-secondary-rgb-dark, 160, 174, 192), 0.1);
    --fc-button-disabled-text-color: var(--color-text-secondary-dark);


    /* Event text color default (though our per-event textColor should override this for event content) */
    /* --fc-event-text-color: var(--color-text-primary-dark); */
}


/* Server List */
.server-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 1rem;
  width: 100%;
}

.server-item {
  background: var(--color-surface);
  padding: 1.5rem;
  border-radius: var(--border-radius-base);
  box-shadow: var(--current-shadow-soft);
  transition: background-color 0.3s ease;
}

.server-item strong {
  font-weight: 600;
  color: var(--color-text-primary);
}

.server-item button {
  margin-right: 0.5rem;
  margin-top: 0.75rem;
}

/* Tables */
.table-container {
  overflow-x: auto;
  margin-top: 1rem;
  background-color: var(--color-surface);
  border-radius: var(--border-radius-base);
  box-shadow: var(--current-shadow-soft);
  border: 1px solid var(--color-border);
  transition: background-color 0.3s ease, border-color 0.3s ease;
}

.responsive-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 500px;
}

.responsive-table th,
.responsive-table td {
  text-align: left;
  padding: 1rem;
  border-bottom: 1px solid var(--color-border);
  vertical-align: middle;
}

.responsive-table th {
  background-color: var(--color-table-header-bg);
  font-weight: 600;
  color: var(--color-text-primary);
  border-bottom-width: 2px; /* Make header bottom border slightly thicker */
  transition: background-color 0.3s ease, color 0.3s ease;
}

.responsive-table tr:last-child td {
  border-bottom: none;
}

.responsive-table tr:hover td {
    background-color: var(--color-table-row-hover-bg);
}

.navbar-header { /* This class might be simplified or merged if not strictly needed */
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-grow: 1; /* Allow it to take space before menu items wrap */
}

/* Responsive Adjustments */
@media (max-width: 768px) {
  .navbar {
    padding: 0.75rem 1rem;
  }
  .navbar-header {
    width: 100%; /* Ensure header takes full width to position toggle */
  }
  .navbar-toggle {
    display: block; /* Show hamburger */
  }
  .navbar-links {
    display: none; /* JS toggles to 'flex' via 'active' class */
    flex-direction: column;
    align-items: flex-start;
    text-align: left;
    width: 100%;
    background-color: var(--color-surface);
    padding: 0.5rem 0;
    box-shadow: var(--current-shadow-soft);
    border-top: 1px solid var(--color-border);
    transition: background-color 0.3s ease, border-color 0.3s ease;
  }
  .navbar-links.active { /* This class is toggled by JS */
    display: flex;
  }
  .navbar-links a {
    padding: 0.75rem 1rem;
    width: 100%;
    box-sizing: border-box;
    border-radius: 0; /* Full width links typically don't have individual radius in dropdown */
  }
  html:not(.dark-mode) .navbar-links a:hover {
      background-color: rgba(52, 73, 94, 0.08);
  }
  html.dark-mode .navbar-links a:hover {
      background-color: rgba(66, 153, 225, 0.12);
  }

  .container {
    padding: 1rem;
  }

  .form-wrapper {
    margin: 1rem auto;
    padding: 1.5rem;
  }

  .responsive-table th,
  .responsive-table td {
    padding: 0.75rem;
    font-size: 0.9rem;
  }
}

@media (min-width: 768px) {
  .server-list {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  }
}

/* Theme toggle button style */
.theme-toggle-button {
  background-color: var(--color-surface);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  padding: 0.5rem 0.75rem;
  border-radius: var(--border-radius-base);
  cursor: pointer;
  font-size: 0.9rem;
  margin-left: 1rem; /* For spacing in navbar */
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.theme-toggle-button:hover {
  opacity: 0.8; /* Simple hover effect */
}

/* In styles.css */
/* ... (other button styles) ... */

button.button-success, input[type="submit"].button-success {
  background-color: var(--color-success-text); /* Using success text color for bg, adjust if needed */
  color: var(--color-surface); /* Assuming success text is dark enough for light text */
}
html.dark-mode button.button-success, html.dark-mode input[type="submit"].button-success {
  background-color: var(--color-success-text-dark);
  color: var(--color-bg-dark);
}
button.button-success:hover, input[type="submit"].button-success:hover {
  opacity: 0.85;
}


button.button-danger, input[type="submit"].button-danger {
  background-color: var(--color-danger-text); /* Using danger text color for bg */
  color: var(--color-surface);
}
html.dark-mode button.button-danger, html.dark-mode input[type="submit"].button-danger {
  background-color: var(--color-danger-text-dark);
  color: var(--color-bg-dark);
}
button.button-danger:hover, input[type="submit"].button-danger:hover {
  opacity: 0.85;
}

button.button-secondary, input[type="submit"].button-secondary {
  background-color: var(--color-text-secondary);
  color: var(--color-surface);
}
html.dark-mode button.button-secondary, html.dark-mode input[type="submit"].button-secondary {
  background-color: var(--color-text-secondary-dark);
  color: var(--color-text-primary-dark); /* Check contrast */
}
button.button-secondary:hover, input[type="submit"].button-secondary:hover {
  opacity: 0.85;
}

/* Smaller buttons for table actions */
.actions-cell button, .actions-cell input[type="submit"] {
  padding: 0.35rem 0.7rem; /* Smaller padding */
  font-size: 0.875rem; /* Smaller font */
  margin-bottom: 0.25rem; /* Space if they stack on very small screens */
}
.actions-cell form {
    margin-bottom: 0.25rem; /* Ensure forms have a bit of space if they stack */
}
.actions-cell form:last-child {
    margin-bottom: 0;
}