:root {
    --bg: #f8fafc;
    --text: #020617;
    --card: #ffffff;
    --shadow: rgba(0,0,0,0.12);
    --primary: #2563eb;
}

body.dark {
    --bg: #020617;
    --text: #e5e7eb;
    --card: #0f172a;
    --shadow: rgba(0,0,0,0.6);
    --primary: #38bdf8;
}

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

body {
    background: var(--bg);
    color: var(--text);
    font-family: "Segoe UI", sans-serif;
}

/* HEADER */
.header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: var(--card);
    padding: 1.2rem 3rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 10px 30px var(--shadow);
}

main {
    padding-top: 100px;
}

/* LOGO */
.logo-container {
    display: flex;
    align-items: center;
    gap: 0.9rem;
}

.logo {
    width: 52px;
    height: 52px;
    border-radius: 50px;
}

.logo-text {
    font-family: "Bungee", sans-serif;
    font-size: 1.4rem;
}

/* NAV */
.nav {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav a {
    font-size: 1.05rem;
    text-decoration: none;
    color: var(--text);
    position: relative;
}

.nav a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 3px;
    background: var(--primary);
    transition: 0.3s;
}

.nav a:hover::after {
    width: 100%;
}

/* TOGGLE */
.theme-toggle {
    width: 48px;
    height: 26px;
    position: relative;
}

.theme-toggle input {
    display: none;
}

.slider {
    background: #cbd5f5;
    border-radius: 50px;
    position: absolute;
    inset: 0;
}

.slider::before {
    content: "";
    width: 20px;
    height: 20px;
    background: white;
    border-radius: 50%;
    position: absolute;
    top: 3px;
    left: 3px;
    transition: 0.3s;
}

input:checked + .slider::before {
    transform: translateX(22px);
}

/* HERO */
.hero {
    background: honeydew;
    padding: 6rem 3rem;
    text-align: center;
}

.hero-content {
    max-width: 900px;
    margin: auto;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-content p {
    font-size: 1.3rem;
    line-height: 1.7;
}

/* ABOUT SECTION */
.about-section {
    padding: 6rem 3rem;
}

.about-container {
    max-width: 1400px;
    margin: auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr); /* SINGLE LINE */
    gap: 2rem;
}

.about-card {
    background: var(--card);
    padding: 2.5rem;
    border-radius: 24px;
    box-shadow: 0 20px 50px var(--shadow);
    transition: transform 0.3s ease;
}

.about-card:hover {
    transform: translateY(-8px);
}

.about-card h2 {
    font-size: 1.6rem;
    margin-bottom: 1rem;
}

.about-card p {
    font-size: 1.05rem;
    line-height: 1.7;
}

/* RESPONSIVE */
@media (max-width: 1100px) {
    .about-container {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .about-container {
        grid-template-columns: 1fr;
    }
}

/* FOOTER */
footer {
    background: var(--card);
    padding: 4rem 2rem;
    text-align: center;
}