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

html,
body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: #f5f5f0;
    color: #333;
    line-height: 1.5;
}

.github-fork-ribbon {
    width: 12.1em;
    height: 12.1em;
    position: absolute;
    overflow: hidden;
    top: 0;
    right: 0;
    z-index: 9999;
    font-size: 13px;
    text-decoration: none;
    text-indent: -999999px;
    pointer-events: none;
}

.github-fork-ribbon.fixed {
    position: fixed;
}

.github-fork-ribbon:hover,
.github-fork-ribbon:focus {
    text-decoration: none;
}

.github-fork-ribbon::before {
    content: attr(data-ribbon);
    color: #fff;
    font: 700 1em "Helvetica Neue", Helvetica, Arial, sans-serif;
    line-height: 1.54em;
    text-decoration: none;
    text-align: center;
    text-indent: 0;
    text-shadow: 0 -1px rgba(0, 0, 0, 0.5);
    position: absolute;
    padding: 0.5em 0;
    background-color: #a00;
    width: 15.38em;
    height: 1.54em;
    top: 3.23em;
    right: -3.23em;
    transform: rotate(45deg);
    box-shadow: 0 0.1em 0.2em rgba(0, 0, 0, 0.5);
    pointer-events: auto;
}

.container {
    max-width: 1400px;
    height: 100vh;
    margin: 0 auto;
    padding: 12px 16px;
    display: flex;
    flex-direction: column;
}

h1 {
    flex-shrink: 0;
    font-size: 1.25rem;
    margin-bottom: 10px;
    text-align: center;
}

.main-layout {
    flex: 1;
    min-height: 0;
    display: grid;
    grid-template-columns: minmax(260px, 340px) 1fr;
    gap: 12px;
}

.form-panel {
    min-height: 0;
    overflow-y: auto;
}

.params-form {
    display: grid;
    grid-template-columns: 1fr;
    gap: 10px;
    background: #fff;
    padding: 16px;
    border-radius: 8px;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.1);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.form-group label {
    font-size: 0.85rem;
    color: #555;
}

.form-group input,
.form-group select {
    padding: 8px 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-size: 0.95rem;
}

.form-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 4px;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: background 0.15s;
}

.btn-primary {
    background: #4a7c59;
    color: #fff;
}

.btn-primary:hover {
    background: #3d6649;
}

.btn-secondary {
    background: #e0e0e0;
    color: #333;
}

.btn-secondary:hover {
    background: #d0d0d0;
}

.error {
    display: none;
    padding: 10px 14px;
    background: #fde8e8;
    color: #c0392b;
    border-radius: 4px;
    margin-top: 12px;
    font-size: 0.9rem;
}

.error.visible {
    display: block;
}

.canvas-wrapper {
    min-height: 0;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.1);
    padding: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

#floor-canvas {
    display: block;
    max-width: 100%;
    max-height: 100%;
}

.app-footer {
    flex-shrink: 0;
    margin-top: 10px;
    padding: 8px 12px;
    text-align: center;
}

.app-footer p {
    font-size: 0.8rem;
    color: #888;
    letter-spacing: 0.02em;
}

.app-footer a {
    color: #5a7a66;
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: color 0.2s, border-color 0.2s;
}

.app-footer .github-link {
    display: inline-flex;
    vertical-align: middle;
    margin: 0 3px;
    border-bottom: none;
    color: #555;
}

.app-footer .github-link:hover {
    color: #24292f;
    border-bottom: none;
}

.app-footer .github-icon {
    width: 16px;
    height: 16px;
    fill: currentColor;
}

.app-footer .heart {
    color: #d4737a;
    font-size: 0.95rem;
    display: inline-block;
    animation: heartbeat 2.4s ease-in-out infinite;
}

.app-footer .dedicated-to {
    color: #6b5b4f;
    font-style: italic;
    font-weight: 500;
}

@keyframes heartbeat {
    0%, 100% { transform: scale(1); }
    15% { transform: scale(1.15); }
    30% { transform: scale(1); }
}

@media (max-width: 860px) {
    html,
    body {
        overflow: auto;
    }

    .container {
        height: auto;
        min-height: 100vh;
    }

    .main-layout {
        grid-template-columns: 1fr;
        grid-template-rows: auto min(52vh, 480px);
    }

    .params-form {
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    }
}