@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+KR:wght@300;500;700&display=swap');

:root {
    --bg: #f3f0ea;
    --panel: #ffffff;
    --text: #2b2a28;
    --muted: #6c6a66;
    --primary: #2f6f4e;
    --primary-strong: #24583e;
    --danger: #c74b4b;
    --border: #e1ddd6;
    --shadow: 0 10px 25px rgba(28, 25, 20, 0.08);
    --seat-scale: 1;
    --gender-male: #2d5e8d;
    --gender-female: #8a4c5b;
}

* {
    box-sizing: border-box;
}

body {
    font-family: "IBM Plex Sans KR", "Segoe UI", sans-serif;
    margin: 24px;
    background: radial-gradient(circle at top, #fff4e6 0%, #f7f2ec 30%, #efeae2 100%);
    color: var(--text);
}

body::before {
    content: "";
    position: fixed;
    inset: -20% 0 auto 0;
    height: 260px;
    background: linear-gradient(120deg, rgba(47, 111, 78, 0.15), rgba(237, 190, 133, 0.2));
    z-index: -1;
}

h1 {
    font-size: 32px;
    margin: 0;
}

h2 {
    margin: 0;
    font-size: 18px;
}

h3 {
    margin: 0 0 10px;
    font-size: 15px;
    color: var(--muted);
}

.hero {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
}

.hero-sub {
    margin: 8px 0 0;
    color: var(--muted);
}

.stepper {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.stepper span {
    padding: 6px 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--border);
    font-size: 12px;
}

.stepper span.active {
    background: rgba(47, 111, 78, 0.14);
    border-color: rgba(47, 111, 78, 0.4);
    color: var(--primary-strong);
}

.container {
    display: grid;
    grid-template-columns: minmax(320px, 1fr) minmax(360px, 1.2fr);
    gap: 20px;
    align-items: start;
}

.controls {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.panel {
    background-color: var(--panel);
    padding: 16px;
    border-radius: 14px;
    box-shadow: var(--shadow);
    animation: rise 0.5s ease both;
}

.panel-inner {
    padding: 12px;
    border-radius: 12px;
    background: #faf7f1;
    border: 1px solid rgba(225, 221, 214, 0.7);
    margin-bottom: 14px;
}

.panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 12px;
}

.step {
    padding: 0;
    overflow: hidden;
}

.step-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 14px 18px;
    background: #f7f4ee;
    border-bottom: 1px solid var(--border);
    cursor: pointer;
}

.step-status {
    font-size: 12px;
    color: var(--muted);
}

.step-content {
    display: none;
    padding: 16px;
}

.step.open .step-content {
    display: block;
}

.step.open .step-header {
    background: #fff;
}

.badge {
    background: #f1efe9;
    color: var(--muted);
    border-radius: 999px;
    padding: 4px 10px;
    font-size: 12px;
}

.hint {
    font-size: 12px;
    color: var(--muted);
    margin: 8px 0 0;
}

.field-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 8px;
    align-items: center;
    margin-bottom: 10px;
}

.field-row.compact {
    margin-top: 12px;
}

input[type="text"],
input[type="number"],
select {
    width: 100%;
    padding: 9px 10px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background-color: #fff;
    font-size: 14px;
}

button {
    background-color: var(--primary);
    color: #fff;
    padding: 10px 15px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    font-size: 14px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

button:hover {
    background-color: var(--primary-strong);
    transform: translateY(-1px);
    box-shadow: 0 8px 16px rgba(47, 111, 78, 0.18);
}

button.secondary {
    background-color: #ece8e0;
    color: var(--text);
    box-shadow: none;
}

button.secondary:hover {
    background-color: #ded8ce;
    transform: translateY(-1px);
}

button.inline {
    width: auto;
    padding: 6px 10px;
    font-size: 12px;
}

button.danger {
    background-color: var(--danger);
}

button.danger:hover {
    background-color: #a94040;
}

button.ghost {
    background: transparent;
    color: var(--text);
    border: 1px dashed var(--border);
}

.button-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
}

#student-list,
#blacklist-list {
    list-style: none;
    padding: 0;
    margin: 12px 0 0;
}

.list-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px;
    border-bottom: 1px solid var(--border);
    gap: 10px;
}

.list-item .meta {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.list-item .subtext {
    font-size: 12px;
    color: var(--muted);
}

.list-actions {
    display: flex;
    gap: 6px;
}

#seating-chart-container {
    background-color: var(--panel);
    padding: 20px;
    border-radius: 16px;
    box-shadow: var(--shadow);
}

.zoom-control {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    color: var(--muted);
}

.zoom-control input {
    width: 110px;
}

.stats {
    font-size: 13px;
    color: var(--muted);
    margin-bottom: 10px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.stats .alert {
    color: var(--danger);
    font-weight: 600;
}

#seating-chart,
.seat-editor {
    display: grid;
    grid-template-columns: repeat(var(--cols, 6), minmax(calc(44px * var(--seat-scale)), 1fr));
    gap: calc(8px * var(--seat-scale));
}

.seat {
    background-color: #eef2ef;
    padding: calc(12px * var(--seat-scale)) calc(6px * var(--seat-scale));
    text-align: center;
    border-radius: 10px;
    min-height: calc(54px * var(--seat-scale));
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
    border: 1px solid transparent;
    transition: background-color 0.2s ease;
}

.seat.occupied {
    background-color: #cfe5d6;
}

.seat.gender-male {
    background-color: color-mix(in srgb, var(--gender-male) 30%, #ffffff);
}

.seat.gender-female {
    background-color: color-mix(in srgb, var(--gender-female) 30%, #ffffff);
}

.seat.disabled {
    background-color: #ddd;
    color: #666;
    font-size: 12px;
}

.seat.conflict {
    border-color: var(--danger);
    box-shadow: 0 0 0 2px rgba(199, 75, 75, 0.15);
}

.seat-name {
    font-weight: 600;
}

.seat-gender {
    font-size: 12px;
    color: var(--muted);
}

.seat-toggle {
    background-color: #f2f2f2;
    color: #333;
    border: 1px solid var(--border);
    padding: 10px 6px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 12px;
    transition: transform 0.2s ease;
}

.seat-toggle:hover {
    transform: translateY(-1px);
}

.seat-toggle.disabled {
    background-color: #555;
    color: #fff;
}

@keyframes rise {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 900px) {
    body {
        margin: 16px;
    }

    .container {
        grid-template-columns: 1fr;
    }

    .zoom-control input {
        width: 140px;
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}