/**
 * ==========================================
 * STYLE.CSS - Główny arkusz stylów aplikacji EffectiveLesson
 * ==========================================
 * 
 * Plik odpowiada za:
 * - Kolorystykę i układ strony
 * - Responsywność (mobile-first)
 * - Animacje i przejścia
 * - Style formularzy i przycisków
 * - Style zakładek (tabs)
 * - Efekty hover i interakcje użytkownika
 * 
 * Struktura:
 * 1. Zmienne CSS (kolory, czcionki)
 * 2. Reset i globalne style
 * 3. Header i nawigacja językowa
 * 4. Zakładki (tabs)
 * 5. Oferta (kafelki)
 * 6. Formularz kontaktowy
 * 7. Loader (ekran ładowania)
 * 8. Debug mode
 * 9. Media queries (responsywność)
 * 10. Animacje
 */

/* ==========================================
   1. ZMIENNE CSS - Centralna paleta kolorów
   ========================================== */
:root { 
    /* Kolory główne */
    --primary: #0062ff;           /* Niebieski główny */
    --primary-dark: #0046b3;      /* Ciemniejszy niebieski */
    --primary-light: #4d9eff;     /* Jasny niebieski */
    --secondary: #d300c5;         /* Fioletowy/różowy akcent */
    --secondary-dark: #a30096;    /* Ciemny fiolet */
    
    /* Kolory statusów */
    --success: #2ecc71;           /* Zielony sukces */
    --error: #ff4d4d;             /* Czerwony błąd */
    --warning: #f39c12;           /* Pomarańczowy ostrzeżenie */
    
    /* Tło i powierzchnie */
    --bg: #f4f7fe;                /* Tło strony */
    --card-bg: #ffffff;           /* Tło kart */
    --hover-bg: #f0f4ff;          /* Tło przy hover */
    
    /* Teksty */
    --text-primary: #333333;      /* Główny tekst */
    --text-secondary: #666666;    /* Drugorzędny tekst */
    --text-light: #999999;        /* Jasny tekst */
    
    /* Cienie */
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.05);
    --shadow-md: 0 5px 15px rgba(0,0,0,0.08);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);
    
    /* Promienie zaokrągleń */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    
    /* Czcionki */
    --font-main: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-mono: 'Courier New', monospace;
}

/* ==========================================
   2. RESET I GLOBALNE STYLE
   ========================================== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body { 
    font-family: var(--font-main);
    background: var(--bg);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ==========================================
   3. HEADER I NAWIGACJA JĘZYKOWA
   ========================================== */
header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    padding: 60px 20px;
    text-align: center;
    position: relative;
    box-shadow: var(--shadow-md);
}

header h1 {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

header p {
    font-size: 1.2rem;
    opacity: 0.95;
    max-width: 700px;
    margin: 0 auto;
}

/* Przełącznik języków z flagami */
.lang-switch { 
    position: absolute;
    top: 25px;
    right: 25px;
    display: flex;
    gap: 12px;
    z-index: 10;
}

.lang-switch a {
    color: white;
    text-decoration: none;
    font-weight: 700;
    font-size: 1rem;
    background: rgba(255,255,255,0.2);
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    border: 2px solid transparent;
}

.lang-switch a:hover {
    background: rgba(255,255,255,0.3);
    border-color: rgba(255,255,255,0.5);
    transform: translateY(-2px);
}

.lang-switch a:active {
    transform: translateY(0);
}

/* Flagi jako emoji (dla maksymalnej kompatybilności) */
.lang-switch a::before {
    font-size: 1.3rem;
}

.lang-switch a[href*="pl"]::before {
    content: "🇵🇱";
}

.lang-switch a[href*="en"]::before {
    content: "🇬🇧";
}

/* ==========================================
   4. KONTENER GŁÓWNY
   ========================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
}

/* ==========================================
   5. ZAKŁADKI (TABS)
   ========================================== */
.tabs-nav {
    display: flex;
    justify-content: center;
    margin-bottom: 40px;
    border-bottom: 3px solid #e0e0e0;
    gap: 5px;
}

.tab-btn {
    padding: 16px 35px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-family: var(--font-main);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-secondary);
    border-bottom: 4px solid transparent;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Efekt podświetlenia przy hover */
.tab-btn::before {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 50%;
    width: 0;
    height: 4px;
    background: var(--primary-light);
    transform: translateX(-50%);
    transition: width 0.3s ease;
}

.tab-btn:hover {
    color: var(--primary);
    transform: translateY(-2px);
}

.tab-btn:hover::before {
    width: 70%;
}

/* Aktywna zakładka */
.tab-btn.active {
    color: var(--primary-dark);
    border-bottom-color: var(--primary);
    background: linear-gradient(to top, var(--hover-bg) 0%, transparent 100%);
}

.tab-btn.active::before {
    width: 100%;
    background: var(--primary);
}

/* Zawartość zakładek */
.tab-content {
    display: none;
    opacity: 0;
    transform: translateY(20px);
}

.tab-content.active {
    display: block !important;
    animation: fadeInUp 0.5s ease forwards;
}

/* ==========================================
   6. OFERTA - KAFELKI
   ========================================== */
.offer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.offer-card {
    background: var(--card-bg);
    padding: 30px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border-left: 6px solid var(--primary);
    text-align: left;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

/* Gradient na hover */
.offer-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(0,98,255,0.03) 0%, rgba(211,0,197,0.03) 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.offer-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-left-color: var(--secondary);
}

.offer-card:hover::before {
    opacity: 1;
}

.offer-card h3 {
    color: var(--primary);
    font-size: 1.4rem;
    margin: 15px 0 10px;
    font-weight: 700;
}

.offer-card p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 1rem;
}

/* Ikony w kafelkach */
.offer-card > div:first-child {
    font-size: 3rem;
    margin-bottom: 10px;
    display: inline-block;
    animation: bounce 2s infinite;
}

/* ==========================================
   7. FORMULARZ KONTAKTOWY
   ========================================== */
.card {
    background: var(--card-bg);
    padding: 40px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    max-width: 650px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 25px;
    display: flex;
    flex-direction: column;
    text-align: left;
}

.form-group label {
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text-primary);
    font-size: 1.05rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 14px 16px;
    border: 2px solid #e0e0e0;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: var(--font-main);
    outline: none;
    transition: all 0.3s ease;
    background: white;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0,98,255,0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* Walidacja - pole poprawne */
.valid {
    border-color: var(--success) !important;
    background: #f0fff4 !important;
}

.valid:focus {
    box-shadow: 0 0 0 3px rgba(46,204,113,0.1) !important;
}

/* Walidacja - pole niepoprawne */
.invalid {
    border-color: var(--error) !important;
    background: #fff5f5 !important;
}

.invalid:focus {
    box-shadow: 0 0 0 3px rgba(255,77,77,0.1) !important;
}

/* Przycisk submit */
.btn-submit {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    border: none;
    padding: 18px 30px;
    border-radius: var(--radius-md);
    font-weight: 700;
    cursor: pointer;
    width: 100%;
    font-size: 1.15rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,98,255,0.3);
    position: relative;
    overflow: hidden;
}

.btn-submit::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn-submit:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,98,255,0.4);
}

.btn-submit:hover::before {
    width: 300px;
    height: 300px;
}

.btn-submit:active {
    transform: translateY(-1px);
}

/* ==========================================
   8. LOADER (Ekran ładowania)
   ========================================== */
#loader-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    z-index: 9999;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    backdrop-filter: blur(5px);
}

.loader-spinner {
    width: 60px;
    height: 60px;
    border: 6px solid rgba(255,255,255,0.2);
    border-top: 6px solid var(--secondary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

#loader-tips {
    margin-top: 25px;
    font-size: 1.2rem;
    font-weight: 600;
    text-align: center;
    animation: pulse 2s ease-in-out infinite;
}

/* ==========================================
   9. KOMUNIKATY (Sukces/Błąd)
   ========================================== */
.message-box {
    padding: 18px 25px;
    border-radius: var(--radius-md);
    margin-bottom: 25px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 12px;
    animation: slideDown 0.4s ease;
}

.message-success {
    background: var(--success);
    color: white;
    border-left: 5px solid #27ae60;
}

.message-error {
    background: var(--error);
    color: white;
    border-left: 5px solid #c0392b;
}

.message-box::before {
    font-size: 1.5rem;
}

.message-success::before {
    content: '✅';
}

.message-error::before {
    content: '❌';
}

/* ==========================================
   10. DEBUG MODE
   ========================================== */
.debug-panel {
    margin-top: 40px;
    padding: 25px;
    background: #1a1a1a;
    color: #00ff00;
    border-radius: var(--radius-md);
    font-family: var(--font-mono);
    font-size: 13px;
    box-shadow: var(--shadow-lg);
    border: 2px solid #333;
}

.debug-panel h3 {
    color: white;
    border-bottom: 2px dotted #555;
    padding-bottom: 10px;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.debug-panel pre {
    background: #0a0a0a;
    padding: 15px;
    border-radius: var(--radius-sm);
    overflow-x: auto;
    border: 1px solid #333;
    line-height: 1.5;
}

.debug-panel strong {
    color: #ffff00;
}

/* ==========================================
   11. ANIMACJE
   ========================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes spin {
    100% {
        transform: rotate(360deg);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.6;
    }
}

@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-10px);
    }
}

/* ==========================================
   12. RESPONSYWNOŚĆ (Mobile-First)
   ========================================== */

/* Tablety (768px i mniej) */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    header p {
        font-size: 1rem;
    }
    
    .lang-switch {
        top: 15px;
        right: 15px;
        gap: 8px;
    }
    
    .lang-switch a {
        padding: 6px 12px;
        font-size: 0.9rem;
    }
    
    .tabs-nav {
        flex-direction: column;
        border-bottom: none;
        gap: 0;
    }
    
    .tab-btn {
        width: 100%;
        border-bottom: 2px solid #e0e0e0;
        padding: 12px;
    }
    
    .tab-btn.active {
        border-left: 5px solid var(--primary);
    }
    
    .offer-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .card {
        padding: 25px;
    }
    
    .container {
        padding: 20px 15px;
    }
}

/* Małe telefony (480px i mniej) */
@media (max-width: 480px) {
    header {
        padding: 40px 15px;
    }
    
    header h1 {
        font-size: 1.6rem;
    }
    
    .btn-submit {
        font-size: 1rem;
        padding: 15px;
    }
    
    .offer-card {
        padding: 20px;
    }
    
    .form-group input,
    .form-group select,
    .form-group textarea {
        font-size: 16px; /* Zapobiega zoom na iOS */
    }
}

/* Duże ekrany (1400px i więcej) */
@media (min-width: 1400px) {
    .container {
        max-width: 1400px;
    }
    
    .offer-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ==========================================
   13. TRYB CIEMNY (opcjonalny, przyszłość)
   ========================================== */
@media (prefers-color-scheme: dark) {
    /* Można dodać style dla dark mode jeśli potrzebne */
}

/* ==========================================
   14. PRINT STYLES (dla wydruku)
   ========================================== */
@media print {
    header, .lang-switch, .tabs-nav, .btn-submit, #loader-overlay {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .offer-card, .card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
}

/* ==========================================
   15. UTILITY CLASSES (pomocnicze)
   ========================================== */
.text-center {
    text-align: center;
}

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

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

.mt-20 {
    margin-top: 20px;
}

.mb-20 {
    margin-bottom: 20px;
}

.hidden {
    display: none !important;
}

.visible {
    display: block !important;
}