/* ===================================
   UniBase Exam Platform - Main Styles
   =================================== */

/* Import Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* ===================================
   CSS Custom Properties (Design Tokens)
   =================================== */
:root {
    /* Primary Colors */
    --color-primary: #1e3a5f;
    --color-primary-dark: #152b47;
    --color-primary-light: #2a4d7a;

    /* Accent Colors */
    --color-accent: #26d0ce;
    --color-accent-dark: #1db5b3;
    --color-accent-light: #4dd9d7;

    /* Neutral Colors */
    --color-white: #ffffff;
    --color-black: #000000;
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    /* Semantic Colors */
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;
    --color-info: #3b82f6;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;

    /* 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: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===================================
   Global Reset & Base Styles
   =================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-gray-800);
    background-color: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

h1 {
    font-size: var(--font-size-5xl);
}

h2 {
    font-size: var(--font-size-4xl);
}

h3 {
    font-size: var(--font-size-3xl);
}

h4 {
    font-size: var(--font-size-2xl);
}

h5 {
    font-size: var(--font-size-xl);
}

h6 {
    font-size: var(--font-size-lg);
}

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

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-accent-dark);
}

/* ===================================
   Layout Utilities
   =================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.container-fluid {
    width: 100%;
    padding: 0 var(--spacing-lg);
}

.section {
    padding: var(--spacing-3xl) 0;
}

.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.flex {
    display: flex;
    gap: var(--spacing-md);
}

.flex-center {
    display: flex;
    justify-content: center;
    align-items: center;
}

.flex-between {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

/* ===================================
   Header & Navigation
   =================================== */
/* ===================================
   Header & Navigation
   =================================== */
header {
    background: rgba(30, 58, 95, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-white);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all var(--transition-base);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    transition: transform var(--transition-fast);
    /* Restore font properties for pages without .logo-text span */
    font-size: var(--font-size-xl);
    font-weight: 800;
    color: var(--color-white);
    letter-spacing: -0.5px;
}

.logo:hover {
    transform: scale(1.02);
}

.logo-img {
    height: 40px;
    width: 40px;
    object-fit: cover;
    border-radius: 50%;
    border: 2px solid rgba(255, 255, 255, 0.2);
    transition: border-color var(--transition-fast);
}

.logo:hover .logo-img {
    border-color: var(--color-accent);
}

.logo-text {
    font-size: var(--font-size-xl);
    font-weight: 800;
    color: var(--color-white);
    letter-spacing: -0.5px;
}

/* Desktop Navigation */
nav ul {
    list-style: none;
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    margin: 0;
    padding: 0;
}

nav a {
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
    font-size: var(--font-size-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

nav a:not(.btn):hover {
    color: var(--color-white);
    background-color: rgba(255, 255, 255, 0.1);
}

/* Active link state (optional, can be added via JS) */
nav a.active {
    background-color: rgba(255, 255, 255, 0.15);
    color: var(--color-accent);
}

.auth-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-left: var(--spacing-md);
    padding-left: var(--spacing-md);
    border-left: 1px solid rgba(255, 255, 255, 0.2);
}

/* Language Selector */
.language-selector {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--color-white);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-md);
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-xs);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    font-family: var(--font-family);
    appearance: none;
    /* Remove default arrow */
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1em;
    padding-right: 2rem;
}

.language-selector:hover {
    background-color: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
}

.language-selector:focus {
    outline: none;
    box-shadow: 0 0 0 2px rgba(38, 208, 206, 0.5);
    border-color: var(--color-accent);
}

.language-selector option {
    background-color: var(--color-primary-dark);
    color: var(--color-white);
}

/* Theme Toggle */
.theme-toggle {
    background: transparent;
    color: var(--color-white);
    border: none;
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    transition: transform var(--transition-spring);
}

.theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
    transform: rotate(15deg) scale(1.1);
}

/* Hidden elements */
.hidden {
    display: none !important;
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-base);
    font-weight: 600;
    text-align: center;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    font-family: var(--font-family);
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
    color: var(--color-white);
    box-shadow: var(--shadow-md);
}

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

.btn-secondary {
    background-color: transparent;
    color: var(--color-white);
    border: 2px solid var(--color-white);
}

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

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

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

.btn-danger {
    background-color: var(--color-error);
    color: var(--color-white);
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-success {
    background-color: var(--color-success);
    color: var(--color-white);
}

.btn-success:hover {
    background-color: #059669;
}

.btn-lg {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: var(--font-size-lg);
}

.btn-sm {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-sm);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* ===================================
   Cards
   =================================== */
.card {
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--color-gray-100);
}

.card-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.card-description {
    color: var(--color-gray-600);
    font-size: var(--font-size-sm);
}

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

.card-footer {
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-gray-100);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    background: linear-gradient(135deg, rgba(30, 58, 95, 0.85) 0%, rgba(21, 43, 71, 0.9) 100%),
        url('../images/hero-background.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    color: var(--color-white);
    padding: var(--spacing-3xl) 0;
    text-align: center;
    position: relative;
}

.hero-title {
    font-size: var(--font-size-5xl);
    color: var(--color-white);
    margin-bottom: var(--spacing-lg);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--color-gray-200);
    margin-bottom: var(--spacing-2xl);
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: var(--spacing-lg);
    justify-content: center;
    flex-wrap: wrap;
}

/* ===================================
   Forms
   =================================== */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    color: var(--color-gray-700);
    font-size: var(--font-size-sm);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--color-gray-300);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-family: var(--font-family);
    transition: all var(--transition-fast);
    background-color: var(--color-white);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(38, 208, 206, 0.1);
}

.form-input.error,
.form-select.error,
.form-textarea.error {
    border-color: var(--color-error);
}

.form-error {
    color: var(--color-error);
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
    display: block;
}

.form-checkbox {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.form-checkbox input {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

/* ===================================
   Test Cards
   =================================== */
.test-card {
    background: linear-gradient(135deg, var(--color-white) 0%, var(--color-gray-50) 100%);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    transition: all var(--transition-base);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.test-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-primary) 100%);
    transform: scaleX(0);
    transition: transform var(--transition-base);
}

.test-card:hover::before {
    transform: scaleX(1);
}

.test-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.test-card-badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    background-color: var(--color-accent);
    color: var(--color-white);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

/* ===================================
   Timer Display
   =================================== */
.timer {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: var(--color-white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    box-shadow: var(--shadow-lg);
    min-width: 200px;
}

.timer.warning {
    background: linear-gradient(135deg, var(--color-warning) 0%, #d97706 100%);
    animation: pulse 1s infinite;
}

.timer.danger {
    background: linear-gradient(135deg, var(--color-error) 0%, #dc2626 100%);
    animation: pulse 0.5s infinite;
}

@keyframes pulse {

    0%,
    100% {
        transform: scale(1);
    }

    50% {
        transform: scale(1.05);
    }
}

/* ===================================
   Question Display
   =================================== */
.question-container {
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--spacing-xl);
}

.question-number {
    color: var(--color-accent);
    font-weight: 700;
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
}

.question-text {
    font-size: var(--font-size-xl);
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-xl);
    line-height: 1.6;
}

.answer-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.answer-option {
    padding: var(--spacing-lg);
    border: 2px solid var(--color-gray-300);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    background-color: var(--color-white);
    font-size: var(--font-size-base);
}

.answer-option:hover {
    border-color: var(--color-accent);
    background-color: var(--color-gray-50);
    transform: translateX(8px);
}

.answer-option.selected {
    border-color: var(--color-accent);
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
    color: var(--color-white);
    font-weight: 600;
}

/* ===================================
   Dashboard Stats
   =================================== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stat-card {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    color: var(--color-white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
}

.stat-value {
    font-size: var(--font-size-4xl);
    font-weight: 800;
    margin-bottom: var(--spacing-sm);
}

.stat-label {
    font-size: var(--font-size-base);
    opacity: 0.9;
}

/* ===================================
   Footer
   =================================== */
footer {
    background-color: var(--color-gray-900);
    color: var(--color-gray-400);
    padding: var(--spacing-2xl) 0;
    margin-top: var(--spacing-3xl);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-lg);
}

.footer-links {
    display: flex;
    gap: var(--spacing-xl);
    list-style: none;
}

.footer-links a {
    color: var(--color-gray-400);
    transition: color var(--transition-fast);
}

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

/* ===================================
   Alerts & Messages
   =================================== */
.alert {
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.alert-success {
    background-color: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--color-success);
}

.alert-error {
    background-color: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--color-error);
}

.alert-warning {
    background-color: #fef3c7;
    color: #92400e;
    border-left: 4px solid var(--color-warning);
}

.alert-info {
    background-color: #dbeafe;
    color: #1e40af;
    border-left: 4px solid var(--color-info);
}

/* ===================================
   Utility Classes
   =================================== */
.mt-1 {
    margin-top: var(--spacing-sm);
}

.mt-2 {
    margin-top: var(--spacing-md);
}

.mt-3 {
    margin-top: var(--spacing-lg);
}

.mt-4 {
    margin-top: var(--spacing-xl);
}

.mb-1 {
    margin-bottom: var(--spacing-sm);
}

.mb-2 {
    margin-bottom: var(--spacing-md);
}

.mb-3 {
    margin-bottom: var(--spacing-lg);
}

.mb-4 {
    margin-bottom: var(--spacing-xl);
}

.p-1 {
    padding: var(--spacing-sm);
}

.p-2 {
    padding: var(--spacing-md);
}

.p-3 {
    padding: var(--spacing-lg);
}

.p-4 {
    padding: var(--spacing-xl);
}

.hidden {
    display: none;
}

.block {
    display: block;
}

.inline-block {
    display: inline-block;
}

/* ===================================
   Mobile Menu Button
   =================================== */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    width: 30px;
    height: 20px;
    position: relative;
    z-index: 1001;
}

.mobile-menu-btn span {
    display: block;
    width: 100%;
    height: 3px;
    background-color: var(--color-white);
    position: absolute;
    left: 0;
    transition: all 0.3s ease;
    border-radius: 3px;
}

.mobile-menu-btn span:nth-child(1) {
    top: 0;
}

.mobile-menu-btn span:nth-child(2) {
    top: 50%;
    transform: translateY(-50%);
}

.mobile-menu-btn span:nth-child(3) {
    bottom: 0;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg);
    top: 50%;
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg);
    top: 50%;
    bottom: auto;
}