:root {
    --primary-bg: #0f172a;
    --secondary-bg: #1e293b;
    --accent-gradient: linear-gradient(135deg, #0f172a 0%, #1e3a8a 100%);
    --text-main: #f8fafc;
    --text-secondary: #94a3b8;
    --action: #3b82f6;
    --success: #10b981;
    --warning: #f59e0b;
    --btn-text: #ffffff;
    --radius-xl: 0.75rem;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--primary-bg);
    color: var(--text-main);
    line-height: 1.6;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

*,
::before,
::after {
    box-sizing: inherit;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-top: 0;
    color: inherit;
}

a,
a:hover,
a:focus {
    text-decoration: none;
    transition: all 0.3s ease-in-out;
    color: inherit;
}

img {
    max-width: 100%;
    display: block;
    height: auto;
}

ul,
ol {
    list-style: none;
    padding: 0;
    margin: 0;
}

button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
    transition: transform 0.2s ease, filter 0.2s ease;
}

button:hover {
    filter: brightness(1.1);
}

button:active {
    transform: scale(0.98);
}

input,
textarea,
select {
    font-family: inherit;
    border-radius: var(--radius-xl);
    outline: none;
}

input:focus {
    box-shadow: 0 0 0 2px var(--action);
}

@media (max-width: 768px) {
    h1 {
        font-size: clamp(1.875rem, 8vw, 2.5rem);
        word-break: break-word;
    }

    h2 {
        font-size: clamp(1.5rem, 6vw, 2rem);
        word-break: break-word;
    }

    h3 {
        font-size: clamp(1.25rem, 5vw, 1.75rem);
    }

    p,
    span,
    a,
    li {
        word-break: break-word;
        overflow-wrap: break-word;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
}

/* ===== header ===== */
#header {
    width: 100%;
}

/* ===== hero_section ===== */
#hero {
    width: 100%;
}

#hero .checkbox-primary:checked {
    background-color: var(--action) !important;
    border-color: var(--action) !important;
}

#hero input::placeholder {
    color: #4b5563;
}

/* ===== problems_section ===== */
#problems {
    width: 100%;
    overflow: hidden;
}

#problems .js-problem-card {
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), border-color 0.3s ease, box-shadow 0.3s ease;
}

#problems .js-problem-card:hover {
    transform: translateY(-10px) !important;
    border-color: var(--action) !important;
    box-shadow: 0 20px 40px -15px rgba(15, 23, 42, 0.5);
}

/* ===== solution_section ===== */
#solution {
    position: relative;
}

/* ===== program_section ===== */
#program {
    width: 100%
}

.js-program-card {
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1)
}

/* ===== advantages_section ===== */
.advantages-card-hover:hover {
    transform: translateY(-8px);
    border-color: var(--action);
}

/* ===== reviews_section ===== */
#reviews {
    width: 100%
}

.js-review-card {
    will-change: transform, opacity;
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1)
}

/* ===== faq_section ===== */
#faq {
    width: 100%;
    position: relative;
}

.js-faq-wrapper {
    transition: all 0.3s ease;
}

.js-faq-wrapper:hover {
    border-color: var(--action);
}

/* ===== final_cta_section ===== */
#register {
    background: var(--accent-gradient);
    width: 100%;
}

#register .input::placeholder {
    color: var(--text-secondary);
    opacity: 0.5;
}

#register .checkbox:checked {
    background-color: var(--action);
    border-color: var(--action);
}

/* ===== footer ===== */
#footer {
    background-color: var(--secondary-bg);
}

.brand-logo img {
    filter: brightness(1.1);
}

#footer i {
    color: var(--action);
}

#footer a:hover {
    color: var(--action);
}