:root {
    --bg-color: #f1f5f9;
    --card-bg: rgba(255, 255, 255, 0.9);
    --text-main: #0f172a;
    --text-muted: #475569;
    --brand-yellow: #f59e0b;
    --brand-blue: #0284c7;
    --accent-color: #f0f9ff;
    --border-color: #cbd5e1;
    --primary-color: #0284c7;
    --primary-hover: #0369a1;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --radius: 12px;
}

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

body {
    font-family: 'Noto Sans JP', 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
}

/* ヘッダーデザイン */
.main-header {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    border-bottom: 3px solid var(--brand-yellow);
    padding: 16px 0;
    color: #ffffff;
    width: 100%;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-md);
}

.main-header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.title-icon {
    width: 32px;
    height: 32px;
    color: var(--brand-yellow);
}

.brand-logo {
    font-weight: 800;
    font-size: 1.4rem;
    color: #ffffff;
    letter-spacing: 0.5px;
}

.btn-home {
    background-color: rgba(255, 255, 255, 0.1);
    color: #ffffff;
    text-decoration: none;
    padding: 8px 18px;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 600;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-home:hover {
    background-color: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
}

.container {
    max-width: 1200px;
    width: 100%;
    padding: 24px;
    margin: 0 auto;
}

/* 使い方アコーディオン */
.info-section {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 24px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    backdrop-filter: blur(8px);
}

.info-header {
    width: 100%;
    padding: 16px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    background-color: rgba(248, 250, 252, 0.8);
    border: none;
    transition: var(--transition);
}

.info-header:hover {
    background-color: rgba(241, 245, 249, 0.9);
}

.info-header h2 {
    font-size: 1.1rem;
    color: var(--brand-blue);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
}

.toggle-icon {
    width: 20px;
    height: 20px;
    transition: transform 0.3s ease;
    fill: var(--text-muted);
}

.info-section.collapsed .toggle-icon {
    transform: rotate(-180deg);
}

.info-content {
    padding: 24px;
    border-top: 1px solid var(--border-color);
    display: block;
}

.info-section.collapsed .info-content {
    display: none;
}

.usage-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 16px;
    margin-bottom: 20px;
}

.usage-step {
    background-color: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px;
    position: relative;
    box-shadow: var(--shadow-sm);
}

.usage-step::before {
    content: attr(data-step);
    position: absolute;
    top: -12px;
    left: 16px;
    background-color: var(--brand-blue);
    color: #ffffff;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

.disclaimer {
    border-top: 1px dashed var(--border-color);
    padding-top: 16px;
    font-size: 0.85rem;
    color: var(--text-muted);
}

.disclaimer p {
    margin-bottom: 8px;
}

/* レイアウト */
.tool-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 24px;
    align-items: start;
}

@media (max-width: 968px) {
    .tool-layout {
        grid-template-columns: 1fr;
    }
}

.settings-panel {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* カード共通 */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(8px);
}

.form-title {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 8px;
}

.section-number {
    background-color: var(--brand-blue);
    color: #ffffff;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

/* 入力要素 */
.input-group {
    margin-bottom: 16px;
}

.input-group:last-child {
    margin-bottom: 0;
}

.input-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text-main);
}

.input-group input[type="number"],
.input-group select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.95rem;
    color: var(--text-main);
    background-color: #ffffff;
    transition: var(--transition);
}

.input-group input[type="number"]:focus,
.input-group select:focus {
    outline: none;
    border-color: var(--brand-blue);
    box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.15);
}

.input-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: 16px;
}

.input-row .input-group {
    margin-bottom: 0;
}

.input-group small {
    display: block;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 4px;
}

/* カラーピッカー付きの列 */
.color-picker-row {
    display: grid;
    grid-template-columns: auto 1fr;
    align-items: center;
    gap: 12px;
}

.color-input-wrapper {
    position: relative;
    width: 40px;
    height: 40px;
    border-radius: 6px;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.color-input-wrapper input[type="color"] {
    position: absolute;
    top: -5px;
    left: -5px;
    width: 50px;
    height: 50px;
    border: none;
    cursor: pointer;
}

/* アクションボタン */
.actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.download-btn {
    background-color: var(--primary-color);
    color: #ffffff;
    border: none;
    border-radius: 8px;
    padding: 14px 24px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    width: 100%;
}

.download-btn:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.download-btn:active {
    transform: translateY(0);
}

/* プレビューパネル */
.preview-panel {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.preview-card {
    display: flex;
    flex-direction: column;
    min-height: 500px;
}

/* 計算値のダッシュボード */
.metrics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: 12px;
    margin-bottom: 20px;
}

.metric-card {
    background-color: rgba(248, 250, 252, 0.9);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 12px;
    text-align: center;
}

.metric-label {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.metric-value {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--brand-blue);
}

.metric-unit {
    font-size: 0.8rem;
    font-weight: 600;
}

/* キャンバスの枠組み */
.canvas-container {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px;
    overflow: hidden; /* スクロールバーを出さずに見切れないようにする */
    min-height: 400px;
    height: 500px;
    max-height: 650px;
    position: relative;
}

#layoutCanvas {
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    min-width: 0;
    min-height: 0;
    box-shadow: var(--shadow-md);
    background-color: #ffffff;
    border-radius: 4px;
    display: block;
}

/* トースト */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background-color: #0f172a;
    color: #ffffff;
    padding: 12px 24px;
    border-radius: 30px;
    font-size: 0.9rem;
    font-weight: 600;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    opacity: 0;
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity 0.3s;
    pointer-events: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.toast.show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.toast-icon {
    color: var(--brand-yellow);
}

/* ズームコントローラー */
.zoom-controls {
    position: absolute;
    bottom: 16px;
    right: 16px;
    display: flex;
    align-items: center;
    gap: 4px;
    background-color: rgba(15, 23, 42, 0.85);
    backdrop-filter: blur(4px);
    padding: 6px 10px;
    border-radius: 30px;
    box-shadow: var(--shadow-lg);
    z-index: 10;
    color: #ffffff;
    user-select: none;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.zoom-controls button {
    background: none;
    border: none;
    color: #ffffff;
    cursor: pointer;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.zoom-controls button:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

.zoom-controls span {
    font-size: 0.85rem;
    font-weight: 700;
    font-family: 'Inter', sans-serif;
    min-width: 48px;
    text-align: center;
}

/* Canvasのズーム・パン状態のスタイル */
#layoutCanvas {
    transform-origin: center center;
    transition: transform 0.05s ease-out;
    cursor: grab;
}

#layoutCanvas:active {
    cursor: grabbing;
}