:root {
    --primary-color: #0f172a; /* Slate 900 */
    --secondary-color: #334155; /* Slate 700 */
    --accent-color: #38bdf8; /* Sky 400 */
    --text-color: #f8fafc; /* Slate 50 */
    --text-muted: #94a3b8; /* Slate 400 */
    --bg-dark: #020617; /* Slate 950 */
    --bg-card: rgba(30, 41, 59, 0.7); /* Glassmorphism base */
    --transition-fast: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    --container-width: 1200px;
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

/* Glassmorphism utility */
.glass {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
}

/* Section common */
section {
    padding: 100px 0;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    letter-spacing: 0.1em;
    position: relative;
    padding-bottom: 15px;
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--accent-color);
}

/* Animations */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Button style */
.btn {
    display: inline-block;
    padding: 12px 32px;
    background: var(--accent-color);
    color: var(--bg-dark);
    font-weight: 700;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: var(--transition-fast);
    text-align: center;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(56, 189, 248, 0.3);
    filter: brightness(1.1);
}

/* Header */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 20px 0;
    transition: var(--transition-fast);
}

header.scrolled {
    background: rgba(2, 6, 23, 0.8);
    backdrop-filter: blur(10px);
    padding: 10px 0;
}

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

.logo img {
    height: 40px;
    width: auto;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a:hover {
    color: var(--accent-color);
}

/* Hero */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(2, 6, 23, 0.6), rgba(2, 6, 23, 0.6)), url('image/back.png') center/cover no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    text-shadow: 0 4px 10px rgba(0,0,0,0.5);
    background: linear-gradient(to right, #fff, var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

/* Contact Form */
.contact-container {
    max-width: 600px;
    margin: 0 auto;
}

.contact-form {
    padding: 40px;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-muted);
}

.form-group input, 
.form-group textarea {
    width: 100%;
    padding: 12px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: #fff;
    outline: none;
    transition: var(--transition-fast);
}

.form-group input:focus, 
.form-group textarea:focus {
    border-color: var(--accent-color);
    background: rgba(255, 255, 255, 0.1);
}

.form-group textarea {
    height: 150px;
    resize: none;
}

#form-status {
    margin-top: 20px;
    text-align: center;
    padding: 10px;
    border-radius: 8px;
    display: none;
}

#form-status.success {
    display: block;
    background: rgba(34, 197, 94, 0.2);
    color: #4ade80;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

#form-status.error {
    display: block;
    background: rgba(239, 68, 68, 0.2);
    color: #f87171;
    border: 1px solid rgba(239, 68, 68, 0.2);
}