/* ======================
   Base Styles
   ====================== */

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

/* CSS Variables */
:root {
    /* Metallic Blue Color Palette */
    --metallic-blue-dark: #0a1929;
    --metallic-blue-base: #1e3a8a;
    --metallic-blue-mid: #3b82f6;
    --metallic-blue-light: #60a5fa;
    --metallic-blue-bright: #93bbfd;
    --metallic-accent: #dbeafe;

    /* Supporting Colors */
    --bg-primary: #030712;
    --bg-secondary: #111827;
    --bg-card: #1f2937;
    --border-color: #374151;
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;

    /* Gradients */
    --gradient-metallic: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 50%, #60a5fa 100%);
    --gradient-dark: linear-gradient(135deg, #0a1929 0%, #1e3a8a 100%);
    --gradient-shine: linear-gradient(135deg, #1476bc 0%, #c0c3e3 50%, #28497c 100%);

    --header-height: 6rem;
}

/* Body */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.6;
}

/* Metallic Background Pattern */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(ellipse at top left, rgba(59, 130, 246, 0.15) 0%, transparent 40%),
        radial-gradient(ellipse at bottom right, rgba(30, 58, 138, 0.15) 0%, transparent 40%);
    pointer-events: none;
    z-index: 1;
}

/* Language Toggle */
.lang-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1001;
    display: flex;
    gap: 5px;
    background: rgba(31, 41, 55, 0.9);
    padding: 5px;
    border-radius: 25px;
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-color);
}

.lang-toggle button {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    padding: 8px 20px;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.lang-toggle button.active {
    background: var(--gradient-metallic);
    color: white;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
}

/* Language specific content */
.ja { display: none; }
.en { display: inline; }

body.lang-ja .ja { display: inline; }
body.lang-ja .en { display: none; }