/* ============================================
   NLNG Attendance App - Global Styles
   Blue & White Theme
   ============================================ */

/* Color Variables - Blue & White Palette */
:root {
    /* Primary Blue Gradient */
    --primary-blue: #0066cc;
    --primary-blue-dark: #0052a3;
    --primary-blue-light: #4d94ff;
    --primary-blue-lighter: #e6f2ff;
    /* Secondary Blues */
    --secondary-blue: #0080ff;
    --tertiary-blue: #1a8cff;
    /* White & Neutrals */
    --white: #ffffff;
    --off-white: #f8fafc;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    /* Status Colors */
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #0080ff;
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 51, 153, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 51, 153, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 51, 153, 0.15);
    --shadow-xl: 0 20px 25px -5px rgba(0, 51, 153, 0.2);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 51, 153, 0.25);
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
}

/* ============================================
   Reset & Base Styles
   ============================================ */

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background: linear-gradient(180deg, var(--white) 0%, var(--off-white) 100%);
    color: var(--gray-700);
    line-height: 1.6;
    letter-spacing: -0.01em;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: var(--gray-900);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

h1 {
    font-size: 2.25rem;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

h2 {
    font-size: 1.875rem;
    color: var(--primary-blue-dark);
}

h3 {
    font-size: 1.5rem;
    color: var(--primary-blue-dark);
}

h4 {
    font-size: 1.25rem;
}

h5 {
    font-size: 1.125rem;
}

h6 {
    font-size: 1rem;
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--gray-600);
}

a {
    color: var(--primary-blue);
    text-decoration: none;
    transition: color var(--transition-base);
    font-weight: 500;
}

    a:hover {
        color: var(--primary-blue-dark);
        text-decoration: underline;
    }

code {
    background: var(--primary-blue-lighter);
    color: var(--primary-blue-dark);
    padding: 0.125rem 0.5rem;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.875em;
}

/* ============================================
   Navigation & Header
   ============================================ */

.navbar {
    background: linear-gradient(90deg, var(--white) 0%, var(--off-white) 100%);
    box-shadow: 0 4px 20px rgba(0, 51, 153, 0.08);
    transition: all var(--transition-base);
    border-bottom: 2px solid var(--primary-blue-lighter);
    padding: 1rem 0;
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.25rem;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 8px;
}

    .navbar-brand i {
        font-size: 1.5rem;
        color: var(--primary-blue);
    }

.nav-link {
    font-weight: 500;
    font-size: 0.95rem;
    color: var(--gray-600) !important;
    transition: all var(--transition-base);
    position: relative;
    margin-left: 0.5rem;
}

    .nav-link:hover,
    .nav-link.active {
        color: var(--primary-blue) !important;
    }

    .nav-link::after {
        content: '';
        position: absolute;
        bottom: -8px;
        left: 0;
        width: 0;
        height: 3px;
        background: linear-gradient(90deg, var(--primary-blue), var(--secondary-blue));
        transition: width var(--transition-base);
        border-radius: var(--radius-full);
    }

    .nav-link:hover::after,
    .nav-link.active::after {
        width: 100%;
    }

/* ============================================
   Cards & Containers
   ============================================ */

.card {
    border: 1px solid var(--primary-blue-lighter);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
    overflow: hidden;
    background: var(--white);
}

    .card:hover {
        box-shadow: var(--shadow-lg);
        transform: translateY(-4px);
        border-color: var(--secondary-blue);
    }

.card-header {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    color: var(--white);
    border: none;
    font-weight: 600;
    padding: var(--spacing-lg);
}

.card-body {
    padding: var(--spacing-lg);
}

.card-footer {
    background: var(--primary-blue-lighter);
    border-top: 1px solid var(--primary-blue-lighter);
    padding: var(--spacing-md);
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    font-weight: 600;
    border-radius: var(--radius-lg);
    padding: 0.625rem 1.25rem;
    transition: all var(--transition-base);
    border: none;
    cursor: pointer;
    font-size: 0.95rem;
    letter-spacing: 0.3px;
}

    .btn:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-lg);
    }

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

.btn-primary {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    color: var(--white);
    box-shadow: 0 10px 25px rgba(0, 51, 153, 0.3);
}

    .btn-primary:hover {
        background: linear-gradient(135deg, var(--primary-blue-dark) 0%, var(--primary-blue) 100%);
        color: var(--white);
    }

.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-900);
}

    .btn-secondary:hover {
        background: var(--gray-300);
        color: var(--gray-900);
    }

.btn-outline-primary {
    border: 2px solid var(--primary-blue);
    color: var(--primary-blue);
    background: transparent;
}

    .btn-outline-primary:hover {
        background: var(--primary-blue);
        color: var(--white);
    }

.btn-lg {
    padding: 0.875rem 2rem;
    font-size: 1rem;
    height: 50px;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    pointer-events: none;
}

/* ============================================
   Forms
   ============================================ */

.form-label {
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: var(--spacing-sm);
    font-size: 0.95rem;
}

.form-control,
.form-select {
    border: 2px solid var(--primary-blue-lighter);
    border-radius: var(--radius-lg);
    padding: 0.625rem 1rem;
    font-size: 0.95rem;
    transition: all var(--transition-base);
    background: var(--white);
    color: var(--gray-900);
}

    .form-control:focus,
    .form-select:focus {
        border-color: var(--primary-blue);
        box-shadow: 0 0 0 4px rgba(0, 102, 204, 0.1);
        outline: none;
        background: var(--white);
    }

    .form-control::placeholder {
        color: var(--gray-400);
    }

.form-check-input {
    border: 2px solid var(--primary-blue-lighter);
    border-radius: var(--radius-md);
    width: 20px;
    height: 20px;
    cursor: pointer;
    transition: all var(--transition-base);
}

    .form-check-input:checked {
        background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
        border-color: var(--primary-blue);
        box-shadow: 0 0 0 4px rgba(0, 102, 204, 0.1);
    }

.form-check-label {
    cursor: pointer;
    user-select: none;
    color: var(--gray-700);
}

/* ============================================
   Alerts
   ============================================ */

.alert {
    border-radius: var(--radius-lg);
    border: none;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 0.95rem;
    border-left: 4px solid transparent;
}

.alert-danger {
    background: #fef2f2;
    color: #991b1b;
    border-left-color: #dc2626;
}

.alert-success {
    background: #f0fdf4;
    color: #15803d;
    border-left-color: #10b981;
}

.alert-warning {
    background: #fffbeb;
    color: #92400e;
    border-left-color: #f59e0b;
}

.alert-info {
    background: var(--primary-blue-lighter);
    color: var(--primary-blue-dark);
    border-left-color: var(--primary-blue);
}

/* ============================================
   Hero Section
   ============================================ */

.hero-section {
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--secondary-blue) 100%);
    color: var(--white);
    padding: 80px 20px;
    position: relative;
    overflow: hidden;
}

    .hero-section::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 600"><path fill="rgba(255,255,255,0.05)" d="M0,300 Q300,250 600,300 T1200,300 L1200,600 L0,600 Z"/></svg>') no-repeat bottom;
        background-size: cover;
        z-index: 0;
    }

    .hero-section .container {
        position: relative;
        z-index: 1;
    }

/* ============================================
   Features Section
   ============================================ */

.features-section {
    background: linear-gradient(180deg, var(--white) 0%, var(--primary-blue-lighter) 100%);
    padding: 80px 20px;
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, rgba(0, 102, 204, 0.1) 0%, rgba(0, 128, 255, 0.1) 100%);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-lg);
    color: var(--primary-blue);
    font-size: 1.5rem;
}

/* ============================================
   CTA Section
   ============================================ */

.cta-section {
    background: linear-gradient(180deg, var(--white) 0%, var(--off-white) 100%);
    border-top: 2px solid var(--primary-blue-lighter);
    padding: 60px 20px;
}

/* ============================================
   Tables
   ============================================ */

.table {
    border-collapse: collapse;
}

    .table thead {
        background: linear-gradient(135deg, var(--primary-blue-lighter) 0%, rgba(0, 128, 255, 0.05) 100%);
        border-bottom: 2px solid var(--primary-blue);
    }

        .table thead th {
            font-weight: 700;
            color: var(--primary-blue-dark);
            padding: var(--spacing-md);
            text-align: left;
        }

    .table tbody td {
        padding: var(--spacing-md);
        border-bottom: 1px solid var(--gray-200);
    }

    .table tbody tr:hover {
        background: var(--primary-blue-lighter);
    }

/* ============================================
   Badges
   ============================================ */

.badge {
    border-radius: var(--radius-full);
    padding: 0.375rem 0.75rem;
    font-weight: 600;
    font-size: 0.875rem;
}

.badge-primary {
    background: var(--primary-blue-lighter);
    color: var(--primary-blue-dark);
}

.badge-success {
    background: #d1fae5;
    color: #065f46;
}

.badge-danger {
    background: #fee2e2;
    color: #7f1d1d;
}

/* ============================================
   Animations
   ============================================ */

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

.slide-up {
    animation: slideUp 0.3s ease;
}

.slide-in {
    animation: slideIn 0.3s ease;
}

/* ============================================
   Footer
   ============================================ */

.footer {
    background: linear-gradient(135deg, var(--gray-900) 0%, var(--primary-blue-dark) 100%);
    color: var(--white);
    padding: var(--spacing-lg);
    text-align: center;
    margin-top: auto;
}

    .footer a {
        color: var(--primary-blue-lighter);
    }

        .footer a:hover {
            color: var(--white);
        }

/* ============================================
   Responsive
   ============================================ */

@media (max-width: 768px) {
    h1 {
        font-size: 1.875rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    h3 {
        font-size: 1.25rem;
    }

    .hero-section,
    .features-section {
        padding: 40px 20px;
    }

    .btn-lg {
        padding: 0.75rem 1.5rem;
        height: 46px;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.5rem;
    }

    h2 {
        font-size: 1.25rem;
    }

    .form-control {
        font-size: 16px;
    }

    .btn {
        width: 100%;
    }
}