:root {
    --bg: #f3f6fb;
    --card: #ffffff;
    --text: #1f2937;
    --muted: #6b7280;
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --border: #e5e7eb;
    --success: #059669;
    --error: #dc2626;
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: linear-gradient(180deg, #eef4ff 0%, var(--bg) 220px);
    color: var(--text);
}

.container {
    width: min(1200px, calc(100% - 32px));
    margin: 0 auto;
    padding: 32px 0 48px;
}

.page-header,
.summary,
.form-actions,
.link-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.page-header {
    margin-bottom: 24px;
}

h1,
h2 {
    margin: 0 0 8px;
}

.subtitle,
small,
.muted {
    color: var(--muted);
}

.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
    padding: 20px;
}

.summary {
    margin-bottom: 24px;
}

.summary-item {
    display: flex;
    flex-direction: column;
    gap: 6px;
    min-width: 180px;
}

.summary-item span {
    color: var(--muted);
    font-size: 14px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 16px;
    border-radius: 10px;
    border: 1px solid transparent;
    text-decoration: none;
    cursor: pointer;
    font-size: 14px;
    transition: 0.2s ease;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-secondary,
.btn-copy {
    background: #fff;
    color: var(--text);
    border-color: var(--border);
}

.btn-secondary:hover,
.btn-copy:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.form-grid {
    display: grid;
    gap: 18px;
}

.form-grid label {
    display: grid;
    gap: 8px;
}

.form-grid input {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid var(--border);
    border-radius: 10px;
    font-size: 15px;
}

.form-grid input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.alert {
    margin-bottom: 16px;
    padding: 12px 16px;
    border-radius: 10px;
}

.alert-success {
    background: #ecfdf5;
    color: var(--success);
    border: 1px solid #a7f3d0;
}

.alert-error {
    background: #fef2f2;
    color: var(--error);
    border: 1px solid #fecaca;
}

.media-list {
    display: grid;
    gap: 16px;
}

.media-row {
    display: grid;
    grid-template-columns: 220px minmax(0, 1fr) minmax(0, 1fr);
    gap: 16px;
    align-items: stretch;
}

.media-preview {
    aspect-ratio: 16 / 9;
    background: #111827;
    border-radius: 12px;
    overflow: hidden;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.media-preview img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.media-preview.no-image .placeholder,
.placeholder {
    color: #d1d5db;
    font-size: 14px;
}

.media-name {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 8px 10px;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.75));
    color: #fff;
    font-size: 12px;
    word-break: break-all;
}

.media-action {
    display: grid;
    gap: 10px;
    align-content: start;
}

.link-text {
    display: block;
    padding: 10px 12px;
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 12px;
    word-break: break-all;
    white-space: normal;
}

.empty-state {
    text-align: center;
    display: grid;
    gap: 16px;
    justify-items: center;
}

.tips ul {
    margin: 0;
    padding-left: 20px;
    color: var(--muted);
    line-height: 1.8;
}

.toast {
    position: fixed;
    left: 50%;
    bottom: 32px;
    transform: translateX(-50%) translateY(20px);
    background: rgba(17, 24, 39, 0.92);
    color: #fff;
    padding: 12px 18px;
    border-radius: 999px;
    opacity: 0;
    transition: 0.25s ease;
    pointer-events: none;
}

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

@media (max-width: 900px) {
    .media-row {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .page-header,
    .summary {
        flex-direction: column;
        align-items: flex-start;
    }

    .summary-item {
        width: 100%;
    }
}