/* ==========================================================================
   Arredonda! - Grade Calculator Styles
   ========================================================================== */

/* CSS Variables for Color Palette */
:root {
    --primary-dark: #05386B;
    --primary-medium: #379683;
    --primary-light: #5CDB95;
    --accent-light: #8EE4AF;
    --background-light: #EDF5E1;
    
    /* Additional colors for better UX */
    --success-color: #28a745;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --info-color: #17a2b8;
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --border-radius: 12px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

/* ==========================================================================
   Base Styles
   ========================================================================== */

* {
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background: linear-gradient(135deg, var(--background-light) 0%, #f8f9fa 100%);
    min-height: 100vh;
    line-height: 1.6;
    color: #333;
}

/* ==========================================================================
   Header Styles
   ========================================================================== */

.header-section {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-medium) 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.header-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 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="75" cy="75" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="50" cy="10" r="0.5" fill="rgba(255,255,255,0.05)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
    pointer-events: none;
}

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

.text-white-75 {
    color: rgba(255, 255, 255, 0.85) !important;
}

.display-4 {
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

/* ==========================================================================
   Main Content Styles
   ========================================================================== */

.main-content {
    flex: 1;
}

/* Card Styles */
.card {
    border-radius: var(--border-radius);
    transition: var(--transition);
    border: none;
}

.main-card {
    background: white;
    box-shadow: var(--box-shadow);
}

.main-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.card-header {
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--accent-light) 100%);
    border-bottom: none;
    border-radius: var(--border-radius) var(--border-radius) 0 0 !important;
    color: var(--primary-dark);
}

.section-title {
    color: var(--primary-dark);
    font-weight: 600;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--accent-light);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* ==========================================================================
   Form Styles
   ========================================================================== */

.form-control {
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: var(--transition);
    background-color: #fff;
}

.form-control:focus {
    border-color: var(--primary-medium);
    box-shadow: 0 0 0 0.2rem rgba(55, 150, 131, 0.25);
    background-color: #fff;
}

.form-control:valid {
    border-color: var(--success-color);
}

.form-control.is-invalid {
    border-color: var(--danger-color);
}

.form-label {
    color: var(--primary-dark);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

/* Grade Input Groups */
.grade-input-group {
    background: #f8f9fa;
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid #e9ecef;
    position: relative;
    transition: var(--transition);
}

.grade-input-group:hover {
    background: #f1f3f4;
    border-color: var(--primary-light);
}

.remove-grade-btn {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
}

/* ==========================================================================
   Button Styles
   ========================================================================== */

.btn {
    border-radius: 8px;
    font-weight: 600;
    padding: 0.75rem 1.5rem;
    transition: var(--transition);
    border: none;
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-medium) 0%, var(--primary-light) 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(55, 150, 131, 0.3);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-medium) 100%);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(55, 150, 131, 0.4);
}

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

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

.btn-outline-secondary {
    border: 2px solid #6c757d;
    color: #6c757d;
    background: transparent;
}

.btn-outline-secondary:hover {
    background: #6c757d;
    color: white;
    transform: translateY(-1px);
}

.btn-danger {
    background: linear-gradient(135deg, #dc3545 0%, #c82333 100%);
}

.btn-danger:hover {
    background: linear-gradient(135deg, #c82333 0%, #bd2130 100%);
    transform: translateY(-1px);
}

/* Loading state */
.btn.loading {
    pointer-events: none;
    opacity: 0.7;
}

.btn.loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    margin: auto;
    border: 2px solid transparent;
    border-top-color: currentColor;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

@keyframes spin {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}

/* ==========================================================================
   Results Card Styles
   ========================================================================== */

.results-card {
    animation: slideInUp 0.5s ease-out;
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-success {
    background: linear-gradient(135deg, var(--success-color) 0%, #20c997 100%);
    color: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
}

.result-warning {
    background: linear-gradient(135deg, var(--warning-color) 0%, #e0a800 100%);
    color: #856404;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
}

.result-danger {
    background: linear-gradient(135deg, var(--danger-color) 0%, #c82333 100%);
    color: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
}

.result-grade {
    font-size: 2.5rem;
    font-weight: bold;
    margin: 0.5rem 0;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.result-message {
    font-size: 1.1rem;
    margin-bottom: 0;
}

/* ==========================================================================
   Info Card Styles
   ========================================================================== */

.info-card {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
}

.info-card .card-header {
    background: linear-gradient(135deg, var(--accent-light) 0%, var(--background-light) 100%);
}

/* ==========================================================================
   Alert Styles
   ========================================================================== */

.alert {
    border-radius: var(--border-radius);
    border: none;
    font-weight: 500;
    animation: slideInDown 0.3s ease-out;
}

@keyframes slideInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.alert-success {
    background: linear-gradient(135deg, var(--success-color) 0%, #20c997 100%);
    color: white;
}

.alert-danger {
    background: linear-gradient(135deg, var(--danger-color) 0%, #c82333 100%);
    color: white;
}

.alert-warning {
    background: linear-gradient(135deg, var(--warning-color) 0%, #e0a800 100%);
    color: #856404;
}

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

.footer-section {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-medium) 100%);
    color: white;
    margin-top: auto;
}

.footer-section a {
    color: var(--accent-light);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--primary-light);
    text-decoration: underline;
}

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

/* Mobile First Approach */
@media (max-width: 576px) {
    .container {
        padding-left: 1rem;
        padding-right: 1rem;
    }
    
    .display-4 {
        font-size: 2rem;
    }
    
    .lead {
        font-size: 1rem;
    }
    
    .card-body {
        padding: 1.5rem 1rem;
    }
    
    .btn-lg {
        padding: 0.75rem 1.25rem;
        font-size: 1rem;
    }
    
    .result-grade {
        font-size: 2rem;
    }
    
    .grade-input-group {
        padding: 0.75rem;
    }
    
    .remove-grade-btn {
        position: static;
        width: 100%;
        margin-top: 0.5rem;
        border-radius: 6px;
        height: auto;
        padding: 0.25rem;
    }
}

/* Tablet */
@media (min-width: 577px) and (max-width: 768px) {
    .display-4 {
        font-size: 2.5rem;
    }
    
    .card-body {
        padding: 2rem 1.5rem;
    }
}

/* Desktop */
@media (min-width: 769px) {
    .main-content {
        padding: 3rem 0;
    }
    
    .card-body {
        padding: 2.5rem;
    }
    
    .grade-input-group {
        padding: 1.25rem;
    }
}

/* Large Desktop */
@media (min-width: 1200px) {
    .container {
        max-width: 1140px;
    }
    
    .main-content {
        padding: 4rem 0;
    }
}

/* ==========================================================================
   Accessibility Improvements
   ========================================================================== */

/* Focus indicators */
.btn:focus,
.form-control:focus {
    outline: 2px solid var(--primary-medium);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --primary-dark: #000;
        --primary-medium: #333;
        --primary-light: #666;
    }
    
    .form-control {
        border-width: 3px;
    }
    
    .btn {
        border-width: 2px;
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ==========================================================================
   Print Styles
   ========================================================================== */

@media print {
    .header-section,
    .footer-section,
    .btn,
    .info-card {
        display: none !important;
    }
    
    .main-content {
        padding: 0;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
    
    body {
        background: white;
    }
}

/* ==========================================================================
   Utility Classes
   ========================================================================== */

.text-gradient {
    background: linear-gradient(135deg, var(--primary-medium) 0%, var(--primary-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.shadow-custom {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.border-gradient {
    border: 2px solid;
    border-image: linear-gradient(135deg, var(--primary-medium) 0%, var(--primary-light) 100%) 1;
}

/* Loading spinner */
.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid #f3f3f3;
    border-top: 2px solid var(--primary-medium);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    display: inline-block;
    margin-right: 0.5rem;
}