/* ==========================================================================
   Task Manager — Custom Styles
   ========================================================================== */

/* ==========================================================================
   TABLE OF CONTENTS
   ==========================================================================
   1.  CSS Variables (Light & Dark Mode)
   2.  Global Reset & Base
   3.  Navigation Bar
   4.  Cards & Containers
   5.  Dashboard Statistics Cards (A3)
   6.  Task List & Due‑Date Colour Coding (A4)
   7.  Badges & Status Indicators
   8.  Buttons & Actions
   9.  Forms & Inputs
   10. Footer
   11. Alerts & Messages
   12. Pagination
   13. Responsive Adjustments
   ========================================================================== */


/* ==========================================================================
   1.  CSS VARIABLES
   ========================================================================== */

/* --------------------------------------------------------------------------
   1.1  Light Mode (Default)
   -------------------------------------------------------------------------- */
:root {
    /* Backgrounds */
    --bg-body: #f8fafc;
    --bg-card: #ffffff;
    --bg-navbar: #0d6efd;
    --bg-footer: #ffffff;
    --bg-input: #ffffff;
    --bg-hover: #f1f5f9;

    /* Text colors */
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --text-white: #ffffff;

    /* Borders */
    --border-color: #e2e8f0;

    /* Shadows */
    --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.10);

    /* Transitions */
    --transition-speed: 0.3s;

    /* Dashboard card colours (used for both modes) */
    --dashboard-primary: #0d6efd;
    --dashboard-success: #198754;
    --dashboard-warning: #ffc107;
    --dashboard-danger: #dc3545;
}

/* --------------------------------------------------------------------------
   1.2  Dark Mode Overrides
   -------------------------------------------------------------------------- */
[data-bs-theme="dark"] {
    /* Backgrounds */
    --bg-body: #0f172a;
    --bg-card: #1e293b;
    --bg-navbar: #0b1120;
    --bg-footer: #1e293b;
    --bg-input: #334155;
    --bg-hover: #334155;

    /* Text colors */
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-white: #ffffff;

    /* Borders */
    --border-color: #334155;

    /* Shadows — deeper in dark mode for visibility */
    --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.6);
}


/* ==========================================================================
   2.  GLOBAL RESET & BASE
   ========================================================================== */

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-body);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease;
}

main {
    flex: 1 0 auto;
}


/* ==========================================================================
   3.  NAVIGATION BAR
   ========================================================================== */

.navbar {
    background-color: var(--bg-navbar) !important;
    transition: background-color var(--transition-speed) ease;
}

.navbar-brand {
    font-weight: 700;
    letter-spacing: -0.5px;
}

.navbar-brand i {
    margin-right: 8px;
}

.navbar .navbar-text {
    color: rgba(255, 255, 255, 0.7) !important;
}

/* Dark mode toggle — consistent with Bootstrap's form-switch */
.form-switch .form-check-input {
    cursor: pointer;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'%3e%3ccircle r='3' fill='rgba%28255,255,255,0.5%29'/%3e%3c/svg%3e");
    transition: background-position 0.15s ease-in-out;
}

.form-switch .form-check-input:checked {
    background-color: #0d6efd;
    border-color: #0d6efd;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'%3e%3ccircle r='3' fill='white'/%3e%3c/svg%3e");
}


/* ==========================================================================
   4.  CARDS & CONTAINERS
   ========================================================================== */

.card {
    border: none;
    border-radius: 12px;
    background-color: var(--bg-card);
    box-shadow: var(--shadow-sm);
    transition: background-color var(--transition-speed) ease,
                box-shadow var(--transition-speed) ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card-header {
    border-radius: 12px 12px 0 0 !important;
    padding: 1rem 1.25rem;
    background-color: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    transition: background-color var(--transition-speed) ease,
                border-color var(--transition-speed) ease;
}


/* ==========================================================================
   5.  DASHBOARD STATISTICS CARDS (A3)
   ========================================================================== */

/* --------------------------------------------------------------------------
   Why we use explicit card classes instead of Bootstrap's bg-* utilities:
   - Ensures consistent styling in both light and dark modes.
   - Allows fine‑grained control over hover effects and transitions.
   - Makes it easier to customise colours without touching Bootstrap's
     core variables.
   -------------------------------------------------------------------------- */

.dashboard-card {
    border: none;
    border-radius: 12px;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
    cursor: default;
}

/* Subtle lift on hover — provides tactile feedback without being jarring */
.dashboard-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12) !important;
}

/* Icon container — semi‑transparent background for depth */
.dashboard-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.18);
    border-radius: 10px;
    flex-shrink: 0;
}

/* Number styling — large, bold, and legible */
.dashboard-number {
    line-height: 1.2;
    font-weight: 700;
}

/* Label — subtle, uppercase, with tracking for readability */
.dashboard-label {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    opacity: 0.8;
}

/* Helper for dark text on light backgrounds (e.g., warning card) */
.text-dark-50 {
    color: rgba(0, 0, 0, 0.6) !important;
}


/* ==========================================================================
   6.  TASK LIST & DUE‑DATE COLOUR CODING (A4)
   ========================================================================== */

/* --------------------------------------------------------------------------
   Base list‑group‑item styles — already defined above, but we extend them
   with border‑left accent colours to indicate urgency.
   -------------------------------------------------------------------------- */

.list-group-item {
    background-color: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px !important;
    margin-bottom: 6px;
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease,
                border-color var(--transition-speed) ease,
                transform 0.15s ease;
}

.list-group-item:hover {
    background-color: var(--bg-hover);
    transform: translateX(4px);
}

.list-group-item a {
    color: var(--text-primary);
    text-decoration: none;
}

.list-group-item .text-muted {
    color: var(--text-muted) !important;
}

/* --------------------------------------------------------------------------
   Due‑date colour coding — border‑left accent acts as a visual priority
   indicator without overwhelming the user with background changes.

   Why border‑left instead of background:
   - Preserves readability of text (no contrast issues).
   - Works consistently in both light and dark modes.
   - Subtle enough for everyday use but noticeable at a glance.
   -------------------------------------------------------------------------- */

/* Overdue — red accent (critical) */
.list-group-item-due-overdue {
    border-left: 5px solid var(--dashboard-danger) !important;
    background-color: rgba(220, 53, 69, 0.04);
}
.list-group-item-due-overdue:hover {
    background-color: rgba(220, 53, 69, 0.08);
}

/* Due soon (within 3 days) — yellow accent (warning) */
.list-group-item-due-soon {
    border-left: 5px solid var(--dashboard-warning) !important;
    background-color: rgba(255, 193, 7, 0.04);
}
.list-group-item-due-soon:hover {
    background-color: rgba(255, 193, 7, 0.08);
}

/* Due far (> 3 days) — green accent (on track) */
.list-group-item-due-far {
    border-left: 5px solid var(--dashboard-success) !important;
    background-color: rgba(25, 135, 84, 0.04);
}
.list-group-item-due-far:hover {
    background-color: rgba(25, 135, 84, 0.08);
}

/* Small status indicator badges (shown next to due date) */
.badge.bg-danger.rounded-pill {
    font-size: 0.7rem;
    padding: 0 0.5rem;
    line-height: 1.4;
}
.badge.bg-warning.rounded-pill {
    font-size: 0.7rem;
    padding: 0 0.5rem;
    line-height: 1.4;
}
.badge.bg-success.rounded-pill {
    font-size: 0.7rem;
    padding: 0 0.5rem;
    line-height: 1.4;
}


/* ==========================================================================
   7.  BADGES & STATUS INDICATORS
   ========================================================================== */

.badge {
    font-weight: 500;
    padding: 0.35em 0.75em;
    border-radius: 20px;
    letter-spacing: 0.3px;
}


/* ==========================================================================
   8.  BUTTONS & ACTIONS
   ========================================================================== */

.btn {
    border-radius: 8px;
    font-weight: 500;
    padding: 0.5rem 1.25rem;
    transition: all 0.15s ease;
}

/* Primary — used for main actions (filter, create, etc.) */
.btn-primary {
    background-color: #2563eb;
    border-color: #2563eb;
}
.btn-primary:hover {
    background-color: #1d4ed8;
    border-color: #1d4ed8;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.35);
}

/* Success — used for "New Task" and "Completed" actions */
.btn-success {
    background-color: #16a34a;
    border-color: #16a34a;
}
.btn-success:hover {
    background-color: #15803d;
    border-color: #15803d;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.35);
}

/* Secondary — used for Reset, Cancel, and back actions */
.btn-secondary {
    background-color: var(--bg-hover);
    border-color: var(--border-color);
    color: var(--text-primary);
}
.btn-secondary:hover {
    background-color: var(--border-color);
    border-color: var(--border-color);
    color: var(--text-primary);
}


/* ==========================================================================
   9.  FORMS & INPUTS
   ========================================================================== */

.form-control,
.form-select {
    background-color: var(--bg-input);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease,
                border-color var(--transition-speed) ease;
}

.form-control:focus,
.form-select:focus {
    background-color: var(--bg-input);
    color: var(--text-primary);
    border-color: #2563eb;
    box-shadow: 0 0 0 0.25rem rgba(37, 99, 235, 0.25);
}

.form-control::placeholder {
    color: var(--text-muted);
}

.form-label {
    color: var(--text-primary);
}


/* ==========================================================================
   10.  FOOTER
   ========================================================================== */

.footer {
    flex-shrink: 0;
    background-color: var(--bg-footer);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0 1.5rem;
    margin-top: 3rem;
    transition: background-color var(--transition-speed) ease,
                border-color var(--transition-speed) ease;
}

.footer .footer-brand {
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--text-primary);
}

.footer .footer-brand i {
    color: #2563eb;
    margin-right: 6px;
}

.footer .footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.15s ease;
}
.footer .footer-links a:hover {
    color: #2563eb;
}

.footer .footer-social a {
    color: var(--text-muted);
    font-size: 1.2rem;
    transition: color 0.15s ease, transform 0.15s ease;
    display: inline-block;
}
.footer .footer-social a:hover {
    color: #2563eb;
    transform: translateY(-2px);
}

.footer .footer-divider {
    border: 0;
    border-top: 1px solid var(--border-color);
    margin: 1rem 0;
}

.footer .footer-copy {
    font-size: 0.85rem;
    color: var(--text-muted);
}
.footer .footer-copy a {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
}
.footer .footer-copy a:hover {
    text-decoration: underline;
}


/* ==========================================================================
   11.  ALERTS & MESSAGES
   ========================================================================== */

.alert {
    background-color: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    box-shadow: var(--shadow-sm);
}


/* ==========================================================================
   12.  PAGINATION
   ========================================================================== */

/* Pagination links inherit the theme colours and maintain consistency */
.pagination .page-link {
    background-color: var(--bg-card);
    color: var(--text-primary);
    border-color: var(--border-color);
    transition: background-color var(--transition-speed) ease,
                color var(--transition-speed) ease,
                border-color var(--transition-speed) ease;
}

.pagination .page-link:hover {
    background-color: var(--bg-hover);
    color: #2563eb;
}

.pagination .page-item.active .page-link {
    background-color: #2563eb;
    border-color: #2563eb;
    color: #ffffff;
}


/* ==========================================================================
   13.  RESPONSIVE ADJUSTMENTS
   ========================================================================== */

@media (max-width: 768px) {
    .footer .footer-links {
        text-align: center;
        margin-top: 0.5rem;
    }

    .footer .footer-social {
        text-align: center;
        margin-top: 0.5rem;
    }

    .footer .footer-brand {
        text-align: center;
        display: block;
    }
}

/* Small screens (phones, < 576px) */
@media (max-width: 576px) {
    /* Dashboard cards — more compact on mobile */
    .dashboard-card .card-body {
        padding: 0.8rem 1rem;
    }

    .dashboard-icon {
        width: 40px;
        height: 40px;
    }
    .dashboard-icon i {
        font-size: 1.5rem !important;
    }

    .dashboard-number {
        font-size: 1.5rem !important;
    }

    /* List items — keep them readable but not too wide */
    .list-group-item {
        padding: 0.75rem 1rem;
    }

    /* Small badge adjustments */
    .badge.rounded-pill {
        font-size: 0.65rem;
    }
}