/* ========================================
   Base Styles
   - Reset
   - Global typography and background
   ======================================== */

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

/* Global */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #1e40af;
    background-image: 
        radial-gradient(circle at 25% 75%, rgba(59, 130, 246, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 75% 25%, rgba(30, 64, 175, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 50% 50%, rgba(37, 99, 235, 0.08) 0%, transparent 60%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* チェックボックス共通スタイル */
input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    width: 24px;
    height: 24px;
    min-width: 24px;
    min-height: 24px;
    max-width: 24px;
    max-height: 24px;
    border: 2px solid #cbd5e0;
    border-radius: 4px;
    background-color: white;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
    transition: all 0.2s ease;
}

input[type="checkbox"]:hover {
    border-color: #3b82f6;
}

input[type="checkbox"]:checked {
    background-color: #3b82f6;
    border-color: #3b82f6;
}

input[type="checkbox"]:checked::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 14px;
    font-weight: bold;
    line-height: 1;
}

input[type="checkbox"]:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

/* ユーティリティクラス: 非表示 */
.hidden {
    display: none !important;
}