:root {
    --primary-red: #E53935;
    --dark-red-glow: #3d0c0c;
    --dark-background: #121212;
    --black-background: #000000;
    --text-light: #FFFFFF;
    --text-secondary: #BDBDBD;
    --box-background: rgba(26, 26, 26, 0.6);
    --border-color: rgba(229, 57, 53, 0.3);
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--black-background);
    background-image: radial-gradient(
        circle at 50% 40%,
        var(--dark-red-glow) 0%,
        var(--dark-background) 35%,
        var(--black-background) 70%
    );
    color: var(--text-light);
    overflow-x: hidden;
    position: relative;
    padding-top: 80px;
}

/* --- Efekty Poświaty (Blur/Glow) --- */
.glow-blur {
    position: fixed;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    filter: blur(150px);
    z-index: -2;
    opacity: 0.4;
}

.glow-blur.red {
    background: var(--primary-red);
    top: -150px;
    left: -200px;
}

.glow-blur.white {
    background: var(--text-secondary);
    bottom: -200px;
    right: -250px;
    opacity: 0.15;
}

/* --- Animowane Tło (Śnieg) --- */
.snowflakes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

.snowflake {
    color: var(--text-secondary);
    font-size: 1em;
    position: absolute;
    top: -10%;
    opacity: 0.5;
    animation: fall linear infinite;
}

@keyframes fall {
    to {
        transform: translateY(105vh);
        opacity: 0;
    }
}

.snowflake:nth-of-type(1) { left: 10%; animation-duration: 12s; }
.snowflake:nth-of-type(2) { left: 20%; animation-duration: 8s; animation-delay: 2s; }
.snowflake:nth-of-type(3) { left: 30%; animation-duration: 15s; }
.snowflake:nth-of-type(4) { left: 40%; animation-duration: 9s; animation-delay: 4s; }
.snowflake:nth-of-type(5) { left: 50%; animation-duration: 11s; }
.snowflake:nth-of-type(6) { left: 60%; animation-duration: 7s; animation-delay: 1s; }
.snowflake:nth-of-type(7) { left: 70%; animation-duration: 14s; }
.snowflake:nth-of-type(8) { left: 80%; animation-duration: 10s; animation-delay: 3s; }
.snowflake:nth-of-type(9) { left: 90%; animation-duration: 13s; }
.snowflake:nth-of-type(10) { left: 5%; animation-duration: 8s; animation-delay: 5s; }

/* --- Nagłówek i Nawigacja --- */
header {
    padding: 20px 5%;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transition: top 0.3s ease-in-out;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 1.3em;
    font-weight: 700;
    color: var(--text-light);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 600;
    transition: color 0.3s ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary-red);
}

/* --- Przyciski --- */
.btn {
    padding: 10px 20px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background-color: var(--primary-red);
    color: var(--text-light);
    box-shadow: 0 0 20px rgba(229, 57, 53, 0.4);
}

.btn-primary:hover {
    filter: brightness(1.2);
    transform: translateY(-2px);
    box-shadow: 0 4px 25px rgba(229, 57, 53, 0.6);
}

.btn-dashboard {
    display: inline-block;
    background-color: var(--primary-red);
    color: var(--text-light);
    font-size: 1.1em;
    padding: 12px 25px;
    margin-top: 20px;
    box-shadow: 0 0 20px rgba(229, 57, 53, 0.4);
}

.btn-dashboard:hover {
    filter: brightness(1.2);
    box-shadow: 0 0 25px rgba(229, 57, 53, 0.6);
}

.btn i,
.nav-links a i,
.logo i {
    margin-right: 8px;
}

.welcome-box .icon {
    transform: none;
}

/* --- Główna Treść --- */
.content {
    padding-top: 100px;
    text-align: center;
}

.hero-section {
    padding: 80px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero-section h1 {
    font-size: 3em;
    color: var(--primary-red);
    letter-spacing: 4px;
    margin-bottom: 10px;
    text-transform: uppercase;
    text-shadow: 0 0 15px rgba(229, 57, 53, 0.5);
}

.hero-section .subtitle {
    font-size: 1.05em;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.welcome-box {
    background: var(--box-background);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 40px;
    max-width: 600px;
    width: 100%;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
}

.welcome-box h2 {
    font-size: 1.8em;
    margin-bottom: 15px;
}

.welcome-box .icon {
    display: inline-block;
    margin-right: 10px;
}

.welcome-box p {
    font-size: 1em;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* --- Sekcja "Features" --- */
.features-section {
    padding: 60px 20px 100px 20px;
    text-align: center;
}

.features-section h2 {
    font-size: 2.5em;
    color: var(--primary-red);
    text-shadow: 0 0 10px rgba(229, 57, 53, 0.5);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 15px;
}

.features-subtitle {
    font-size: 1.1em;
    color: var(--text-secondary);
    margin-bottom: 50px;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
    text-align: left;
}

.feature-card {
    background: var(--box-background);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 30px;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.feature-icon {
    width: 70px;
    height: 70px;
    margin-bottom: 25px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(145deg, rgba(229, 57, 53, 0.3), rgba(229, 57, 53, 0.1));
    border: 1px solid rgba(229, 57, 53, 0.2);
}

.feature-icon i {
    font-size: 2em;
    color: var(--primary-red);
    text-shadow: 0 0 15px var(--primary-red);
}

.feature-card h3 {
    font-size: 1.4em;
    margin-bottom: 10px;
    color: var(--text-light);
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* --- Sekcja "Pricing" --- */
.pricing-section {
    padding: 60px 20px 100px 20px;
    text-align: center;
}

.pricing-section h2 {
    font-size: 2.2em;
    color: var(--primary-red);
    text-shadow: 0 0 10px rgba(229, 57, 53, 0.5);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 15px;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
    max-width: 1100px;
    margin: 0 auto;
    align-items: center;
}

.pricing-card {
    background: var(--box-background);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 30px 25px;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    text-align: center;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.pricing-card.popular {
    transform: scale(1.05);
    border: 2px solid var(--primary-red);
}

.plan-icon {
    font-size: 2.2em;
    color: var(--primary-red);
    margin-bottom: 20px;
}

.pricing-card h3 {
    font-size: 1.4em;
    font-weight: 600;
    margin-bottom: 10px;
}

.plan-price {
    font-size: 2em;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 5px;
}

.plan-cycle {
    color: var(--text-secondary);
    margin-bottom: 20px;
    font-size: 0.9em;
}

.pricing-card hr {
    border: 0;
    height: 1px;
    background-color: var(--border-color);
    margin-bottom: 20px;
}

.plan-features {
    list-style: none;
    text-align: left;
    margin-bottom: 30px;
    font-size: 0.85em;
    flex-grow: 1;
}

.plan-features li {
    margin-bottom: 10px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    line-height: 1.4;
}

.plan-features li span {
    flex: 1;
    word-wrap: break-word;
}

.plan-features li.included {
    color: var(--text-light);
}

.plan-features li.excluded {
    color: var(--text-secondary);
    text-decoration: line-through;
}

.plan-features li i {
    font-size: 1.1em;
    margin-top: 2px;
    flex-shrink: 0;
}

.plan-features li i.fa-circle-check {
    color: var(--primary-red);
}

.plan-features li i.fa-circle-xmark {
    color: #616161;
}

.btn-pricing {
    display: block;
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    background-color: var(--primary-red);
    color: var(--text-light);
    box-shadow: 0 0 20px rgba(229, 57, 53, 0.4);
    margin-top: auto;
}

.btn-pricing:hover {
    filter: brightness(1.2);
    transform: scale(1.02);
}

.btn-pricing i {
    margin-left: 8px;
    transition: transform 0.3s ease;
}

.btn-pricing:hover i {
    transform: translateX(5px);
}

.popular-ribbon {
    width: 150px;
    height: 150px;
    position: absolute;
    top: -10px;
    right: -10px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.popular-ribbon span {
    width: 225px;
    position: absolute;
    padding: 8px 0;
    background-color: var(--primary-red);
    box-shadow: 0 5px 10px rgba(0,0,0,0.1);
    color: var(--text-light);
    font-weight: 600;
    font-size: 0.9em;
    text-transform: uppercase;
    text-align: center;
    transform: rotate(45deg) translateY(-20px);
    transform-origin: center;
}

.watermark {
    position: fixed;
    bottom: 10px;
    right: 15px;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.2);
    z-index: 1001;
    font-family: 'Poppins', sans-serif;
}

/* ============================================= */
/* === MEDIA QUERIES - MOBILE OPTIMIZATION === */
/* ============================================= */

/* Tablet and below */
@media (max-width: 992px) {
    .features-grid {
        grid-template-columns: 1fr 1fr;
    }

    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 450px;
    }

    .pricing-card.popular {
        transform: scale(1);
    }

    .hero-section h1 {
        font-size: 2.3em;
        letter-spacing: 2px;
    }

    .hero-section .subtitle {
        font-size: 0.95em;
    }

    .features-section h2,
    .pricing-section h2 {
        font-size: 2em;
    }
}

/* Mobile phones - CÂN BẰNG KÍCH THƯỚC */
@media (max-width: 768px) {
    body {
        padding-top: 70px;
        font-size: 15px; /* Tăng từ 14px lên 15px */
    }

    header {
        padding: 15px 4%;
    }

    .logo {
        font-size: 1em; /* Tăng từ 0.825em lên 1em */
    }

    .btn-primary {
        padding: 8px 14px; /* Tăng padding */
        font-size: 0.85em; /* Tăng từ 0.64em lên 0.85em */
    }

    .btn-primary i {
        margin-right: 5px;
    }

    .btn-text {
        display: inline; /* Hiển thị text trên mobile */
    }

    .content {
        padding-top: 60px;
    }

    .hero-section {
        padding: 50px 20px; /* Tăng padding */
    }

    .hero-section h1 {
        font-size: 1.8em; /* Tăng từ 1.35em lên 1.8em */
        letter-spacing: 1.5px;
        margin-bottom: 12px;
    }

    .hero-section .subtitle {
        font-size: 0.95em; /* Tăng từ 0.675em lên 0.95em */
        margin-bottom: 30px;
        padding: 0 10px;
        line-height: 1.5;
    }

    .welcome-box {
        padding: 30px 25px; /* Tăng padding */
    }

    .welcome-box h2 {
        font-size: 1.5em; /* Tăng từ 1.3em lên 1.5em */
        margin-bottom: 15px;
    }

    .welcome-box p {
        font-size: 0.95em; /* Tăng từ 0.9em lên 0.95em */
        line-height: 1.6;
    }

    .btn-dashboard {
        font-size: 1em; /* Tăng từ 0.95em lên 1em */
        padding: 12px 24px;
        margin-top: 20px;
    }

    /* Features Section Mobile */
    .features-section,
    .pricing-section {
        padding: 50px 20px 70px 20px; /* Tăng padding */
    }

    .features-section h2,
    .pricing-section h2 {
        font-size: 1.9em; /* Tăng từ 1.6em lên 1.9em */
        letter-spacing: 1.5px;
        margin-bottom: 12px;
    }

    .features-subtitle {
        font-size: 0.95em; /* Tăng từ 0.9em lên 0.95em */
        margin-bottom: 35px;
        padding: 0 10px;
    }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 25px; /* Tăng gap */
        text-align: center;
    }

    .feature-card {
        padding: 25px 20px; /* Tăng padding */
    }

    .feature-icon {
        width: 65px; /* Tăng từ 60px lên 65px */
        height: 65px;
        margin: 0 auto 18px;
    }

    .feature-icon i {
        font-size: 1.6em; /* Tăng từ 1.5em lên 1.6em */
    }

    .feature-card h3 {
        font-size: 1.2em; /* Tăng từ 1.1em lên 1.2em */
        margin-bottom: 10px;
    }

    .feature-card p {
        font-size: 0.95em; /* Tăng từ 0.9em lên 0.95em */
        line-height: 1.6;
    }

    /* Pricing Cards Mobile */
    .pricing-grid {
        gap: 25px; /* Tăng gap */
        max-width: 100%;
        padding: 0 15px;
    }

    .pricing-card {
        padding: 30px 25px; /* Tăng padding */
    }

    .plan-icon {
        font-size: 2em; /* Tăng từ 1.8em lên 2em */
        margin-bottom: 18px;
    }

    .pricing-card h3 {
        font-size: 1.3em; /* Tăng từ 1.2em lên 1.3em */
        margin-bottom: 10px;
    }

    .plan-price {
        font-size: 1.8em; /* Tăng từ 1.6em lên 1.8em */
    }

    .plan-cycle {
        font-size: 0.9em; /* Tăng từ 0.85em lên 0.9em */
        margin-bottom: 18px;
    }

    .plan-features {
        font-size: 0.88em; /* Tăng từ 0.8em lên 0.88em */
        margin-bottom: 25px;
    }

    .plan-features li {
        margin-bottom: 10px; /* Tăng từ 8px lên 10px */
        gap: 10px;
    }

    .btn-pricing {
        padding: 12px; /* Tăng từ 10px lên 12px */
        font-size: 0.95em; /* Tăng từ 0.9em lên 0.95em */
    }

    .popular-ribbon {
        width: 130px; /* Tăng từ 120px lên 130px */
        height: 130px;
    }

    .popular-ribbon span {
        width: 190px; /* Tăng từ 180px lên 190px */
        padding: 7px 0; /* Tăng từ 6px lên 7px */
        font-size: 0.8em; /* Tăng từ 0.75em lên 0.8em */
    }

    .watermark {
        font-size: 11px; /* Tăng từ 10px lên 11px */
        bottom: 10px;
        right: 12px;
    }

    /* Glow effects on mobile */
    .glow-blur {
        width: 450px; /* Tăng từ 400px lên 450px */
        height: 450px;
    }
}

/* Extra small phones - CÂN BẰNG */
@media (max-width: 480px) {
    body {
        font-size: 14px;
    }

    .logo {
        font-size: 0.9em; /* Tăng từ 0.75em lên 0.9em */
    }

    .hero-section h1 {
        font-size: 1.5em; /* Tăng từ 1.125em lên 1.5em */
        letter-spacing: 1px;
    }

    .hero-section .subtitle {
        font-size: 0.85em; /* Tăng từ 0.6em lên 0.85em */
    }

    .btn-primary {
        font-size: 0.8em; /* Tăng từ 0.6em lên 0.8em */
        padding: 8px 12px;
    }

    .welcome-box {
        padding: 25px 20px;
    }

    .welcome-box h2 {
        font-size: 1.3em; /* Tăng từ 1.15em lên 1.3em */
    }

    .welcome-box p {
        font-size: 0.9em;
    }

    .features-section h2,
    .pricing-section h2 {
        font-size: 1.6em; /* Tăng từ 1.4em lên 1.6em */
    }

    .plan-price {
        font-size: 1.6em; /* Tăng từ 1.4em lên 1.6em */
    }

    .plan-features {
        font-size: 0.82em; /* Tăng từ 0.75em lên 0.82em */
    }
}