/* --- DESIGN SYSTEM --- */
:root {
    --color-primary: #e67e22; /* Terracotta */
    --color-primary-hover: #d35400;
    --color-secondary: #2c3e50; /* Dark Slate */
    --color-bg-light: #fdfbf7; /* Cream/Off-white */
    --color-bg-white: #ffffff;
    --color-text-main: #333333;
    --color-text-muted: #666666;
    --color-border: #eeeeee;
    --color-shadow: rgba(0, 0, 0, 0.08);

    --container-width: 1100px;
    --section-padding: 80px 20px;
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

/* --- RESET & BASE --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: var(--color-text-main);
    background-color: var(--color-bg-white);
}

ul {
    list-style: none;
}

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

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

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: var(--section-padding);
}

.section-padding {
    padding: var(--section-padding);
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 2.2rem;
    color: var(--color-secondary);
    margin-bottom: 15px;
}

.section-header p {
    color: var(--color-text-muted);
    font-size: 1.1rem;
}

.section-alt {
    background-color: var(--color-bg-light);
}

/* --- TYPOGRAPHY --- */
h1, h2, h3, h4 {
    color: var(--color-secondary);
    line-height: 1.2;
}

h1 { font-size: 3rem; margin-bottom: 20px; }
h2 { font-size: 2.2rem; }
h3 { font-size: 1.5rem; margin-bottom: 15px; }
h4 { font-size: 1.2rem; }

/* --- BUTTONS --- */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    border: none;
}

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

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

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

.btn-secondary:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

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

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

.btn-block {
    display: block;
    width: 100%;
}

/* --- HEADER & NAV --- */
.main-header {
    background-color: var(--color-bg-white);
    box-shadow: 0 2px 10px var(--color-shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
}

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

.logo a {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--color-secondary);
}

.main-nav ul {
    display: flex;
    gap: 30px;
}

.main-nav a {
    font-weight: 500;
    color: var(--color-text-main);
}

.main-nav a:hover {
    color: var(--color-primary);
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
}

.hamburger, .hamburger::before, .hamburger::after {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--color-secondary);
    position: relative;
    transition: var(--transition);
}

.hamburger::before, .hamburger::after {
    content: '';
    position: absolute;
}

.hamburger::before { top: -8px; }
.hamburger::after { bottom: -8px; }

/* --- HERO --- */
.hero {
    padding: 100px 0;
    background: linear-gradient(135deg, #fff 0%, #fdfbf7 100%);
    overflow: hidden;
}

.hero .container {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    align-items: center;
    gap: 40px;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 25px;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--color-text-muted);
    margin-bottom: 35px;
    max-width: 600px;
}

.hero-actions {
    display: flex;
    gap: 15px;
}

.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
}

.css-decoration {
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, var(--color-primary) 0%, transparent 70%);
    opacity: 0.15;
    border-radius: 50%;
    position: relative;
}

.css-decoration::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 200px;
    height: 200px;
    border: 2px dashed var(--color-primary);
    border-radius: 50%;
    animation: rotate 20s linear infinite;
}

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

/* --- GRIDS & CARDS --- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 25px; }
.grid-5 { display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px; }
.grid-6 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }

.card {
    background: var(--color-bg-white);
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: 0 4px 15px var(--color-shadow);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px var(--color-shadow);
}

/* Category Cards */
.category-card {
    text-align: center;
}

.card-icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.card-link {
    margin-top: auto;
    font-weight: 600;
    color: var(--color-primary);
}

/* Product Cards */
.product-card {
    padding: 0;
    overflow: hidden;
}

.product-image-placeholder {
    width: 100%;
    height: 200px;
    background-color: #f0f0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #ccc;
    font-size: 0.9rem;
}

.product-info {
    padding: 25px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.product-info .btn {
    margin-top: auto;
}

.product-type {
    font-size: 0.8rem;
    text-transform: uppercase;
    color: var(--color-primary);
    font-weight: 700;
    letter-spacing: 1px;
}

.product-features {
    margin: 15px 0;
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

.product-desc {
    font-size: 0.95rem;
    margin-bottom: 20px;
}

/* Guide Cards */
.guide-card {
    padding: 25px;
}

.guide-card h3 {
    font-size: 1.25rem;
    margin-bottom: 10px;
}

.guide-card p {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    margin-bottom: 20px;
}

.card-link {
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--color-primary);
}

/* --- INFO BLOCKS (HOW TO CHOOSE) --- */
.info-block {
    text-align: center;
    padding: 20px;
}

.info-icon {
    font-size: 2rem;
    margin-bottom: 15px;
}

.info-block h4 {
    margin-bottom: 10px;
}

.info-block p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

/* --- CALCULATOR --- */
.calculator-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: start;
}

.calculator-text h2 {
    margin-bottom: 20px;
}

.calculator-form {
    background: var(--color-bg-white);
    padding: 35px;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 30px var(--color-shadow);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    font-size: 1rem;
}

.calculator-results {
    margin-top: 30px;
    padding: 25px;
    background: var(--color-bg-light);
    border-radius: var(--border-radius);
}

.result-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 12px;
}

.result-label {
    color: var(--color-text-muted);
}

.result-value {
    font-weight: 700;
    color: var(--color-secondary);
}

.result-item hr {
    margin: 15px 0;
    border: none;
    border-top: 1px solid var(--color-border);
}

/* --- FOOTER --- */
.main-footer {
    background-color: var(--color-secondary);
    color: white;
    padding: 60px 0 30px;
}

.footer-container {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 40px;
}

.footer-brand h4 {
    color: white;
    margin-bottom: 15px;
}

.footer-brand p {
    color: #bdc3c7;
    font-size: 0.9rem;
}

.footer-nav ul {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-nav a {
    color: #bdc3c7;
    font-size: 0.9rem;
}

.footer-nav a:hover {
    color: white;
}

.footer-notice {
    grid-column: 1 / -1;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.8rem;
    color: #95a5a6;
}

/* --- RESPONSIVE --- */
@media (max-width: 992px) {
    .grid-6, .grid-5, .grid-4, .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .hero-content h1 { font-size: 2.5rem; }
    .hero-actions { justify-content: center; }
    .calculator-container { grid-template-columns: 1fr; }
    .footer-container { grid-template-columns: 1fr; text-align: center; }
    .footer-nav ul { align-items: center; }
}

@media (max-width: 768px) {
    .grid-6, .grid-5, .grid-4, .grid-3 {
        grid-template-columns: 1fr;
    }

    .menu-toggle {
        display: block;
    }

    .main-nav {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: var(--color-bg-white);
        transition: 0.4s ease;
        padding: 40px;
    }

    .main-nav.active {
        left: 0;
    }

    .main-nav ul {
        flex-direction: column;
        gap: 25px;
        text-align: center;
    }

    .main-nav a {
        font-size: 1.2rem;
    }

    .hero-content h1 { font-size: 2.2rem; }
    .section-padding { padding: 60px 20px; }
}