/* ==========================================================================
   RUTS Digital Knowledge & Video Showcase (ภูมิพลังแห่งปัญญา คลังความรู้ มทร.ศรีวิชัย)
   Version: 1.6.0 (Strict Authentication Required for Submissions)
   ========================================================================== */

:root {
    --ruts-navy-dark: #0B3C5D;
    --ruts-navy: #0D3C75;
    --ruts-navy-light: #1E5194;
    --ruts-yellow-warm: #FFF3C4;
    --ruts-gold: #F4C430;
    --ruts-gold-hover: #E6A100;
    --ruts-bg-light: #F8FAFC;
    --ruts-text-dark: #1E293B;
    --ruts-text-muted: #64748B;
    --ruts-border: #E2E8F0;
    --ruts-radius: 12px;
    --ruts-shadow: 0 4px 15px rgba(13, 60, 117, 0.08);
    --ruts-shadow-hover: 0 10px 25px rgba(13, 60, 117, 0.15);
    --ruts-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Container */
.ruts-km-container {
    font-family: 'Sarabun', 'Prompt', system-ui, -apple-system, sans-serif;
    max-width: 1240px;
    margin: 0 auto;
    padding: 20px 10px;
    color: var(--ruts-text-dark);
}

/* 1. Header Banner */
.ruts-km-header {
    background: linear-gradient(135deg, #FFF5D6 0%, var(--ruts-yellow-warm) 100%);
    border: 2px solid #FFE699;
    border-radius: var(--ruts-radius);
    padding: 24px 30px;
    margin-bottom: 25px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--ruts-shadow);
}

.ruts-km-brand {
    display: flex;
    align-items: center;
    gap: 20px;
}

.ruts-km-logo-badge {
    background: var(--ruts-navy);
    color: #FFFFFF;
    font-weight: 700;
    font-size: 18px;
    padding: 12px 20px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 4px 10px rgba(13, 60, 117, 0.2);
}

.ruts-km-title {
    color: var(--ruts-navy);
    font-size: 26px;
    font-weight: 800;
    margin: 0 0 4px 0;
    line-height: 1.2;
}

.ruts-km-subtitle {
    color: #4A5568;
    font-size: 15px;
    font-weight: 500;
    margin: 0;
}

/* 2. Toolbar */
.ruts-km-toolbar {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-bottom: 25px;
}

.ruts-km-search-box {
    position: relative;
    max-width: 500px;
    width: 100%;
}

.ruts-km-search-box .search-icon {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--ruts-navy);
    font-size: 16px;
}

.ruts-km-search-box input {
    width: 100%;
    padding: 12px 40px 12px 45px;
    border: 2px solid var(--ruts-border);
    border-radius: 30px;
    font-size: 15px;
    background: #FFFFFF;
    transition: var(--ruts-transition);
    outline: none;
}

.ruts-km-search-box input:focus {
    border-color: var(--ruts-navy);
    box-shadow: 0 0 0 4px rgba(13, 60, 117, 0.1);
}

#ruts-km-search-clear {
    position: absolute;
    right: 14px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--ruts-text-muted);
    cursor: pointer;
    font-size: 16px;
}

/* Category Filter Tabs */
.ruts-km-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.ruts-km-tab {
    background: #FFFFFF;
    color: var(--ruts-navy);
    border: 1.5px solid #CBD5E1;
    padding: 8px 18px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--ruts-transition);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.ruts-km-tab:hover {
    background: var(--ruts-yellow-warm);
    border-color: var(--ruts-gold);
    color: var(--ruts-navy-dark);
}

.ruts-km-tab.active {
    background: var(--ruts-navy);
    color: #FFFFFF;
    border-color: var(--ruts-navy);
    box-shadow: 0 4px 10px rgba(13, 60, 117, 0.25);
}

/* 3. Grid System & Cards */
.ruts-km-grid {
    display: grid;
    gap: 24px;
    transition: opacity 0.25s ease;
}

.ruts-km-grid.cols-3 { grid-template-columns: repeat(auto-fill, minmax(340px, 1fr)); }
.ruts-km-grid.cols-2 { grid-template-columns: repeat(auto-fill, minmax(450px, 1fr)); }

.ruts-km-card {
    background: #FFFFFF;
    border: 1px solid var(--ruts-border);
    border-radius: var(--ruts-radius);
    overflow: hidden;
    box-shadow: var(--ruts-shadow);
    transition: var(--ruts-transition);
    display: flex;
    flex-direction: column;
}

.ruts-km-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--ruts-shadow-hover);
    border-color: var(--ruts-gold);
}

.ruts-km-thumb-wrapper {
    position: relative;
    width: 100%;
    padding-top: 56.25%;
    background: #000000;
    overflow: hidden;
}

.ruts-km-thumb-wrapper img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}

.ruts-km-card:hover .ruts-km-thumb-wrapper img {
    transform: scale(1.05);
}

.ruts-km-cat-badge {
    position: absolute;
    top: 12px;
    left: 12px;
    background: rgba(13, 60, 117, 0.9);
    color: var(--ruts-gold);
    font-size: 12px;
    font-weight: 700;
    padding: 4px 10px;
    border-radius: 6px;
    backdrop-filter: blur(4px);
    z-index: 2;
}

.ruts-km-duration {
    position: absolute;
    bottom: 12px;
    right: 12px;
    background: rgba(0, 0, 0, 0.8);
    color: #FFFFFF;
    font-size: 11px;
    font-weight: 600;
    padding: 3px 8px;
    border-radius: 4px;
    z-index: 2;
}

.ruts-km-play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 56px;
    height: 56px;
    background: rgba(13, 60, 117, 0.85);
    border: 2px solid var(--ruts-gold);
    color: var(--ruts-gold);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    cursor: pointer;
    transition: var(--ruts-transition);
    z-index: 3;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.ruts-km-card:hover .ruts-km-play-btn {
    background: var(--ruts-gold);
    color: var(--ruts-navy);
    transform: translate(-50%, -50%) scale(1.15);
}

.ruts-km-card-body {
    padding: 20px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.ruts-km-card-title {
    font-size: 17px;
    font-weight: 700;
    margin: 0 0 10px 0;
    line-height: 1.4;
}

.ruts-km-card-title a {
    color: var(--ruts-text-dark);
    text-decoration: none;
    transition: color 0.2s ease;
}

.ruts-km-card-title a:hover {
    color: var(--ruts-navy);
}

.ruts-km-meta-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: var(--ruts-text-muted);
    margin-bottom: 12px;
    padding-bottom: 10px;
    border-bottom: 1px dashed var(--ruts-border);
}

.ruts-km-author {
    font-weight: 600;
    color: var(--ruts-navy);
}

.ruts-km-excerpt {
    font-size: 14px;
    color: var(--ruts-text-muted);
    line-height: 1.5;
    margin-bottom: 16px;
    flex-grow: 1;
}

.ruts-km-card-actions {
    display: flex;
    gap: 8px;
    margin-top: auto;
}

.ruts-km-btn-watch {
    flex: 2;
    background: var(--ruts-navy);
    color: #FFFFFF;
    border: none;
    padding: 9px 12px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 13px;
    cursor: pointer;
    transition: var(--ruts-transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.ruts-km-btn-watch:hover {
    background: var(--ruts-navy-dark);
    box-shadow: 0 4px 10px rgba(13, 60, 117, 0.3);
}

.ruts-km-btn-download {
    flex: 1;
    background: #FFF3C4;
    color: #856404;
    border: 1px solid #FFEBAA;
    padding: 9px 12px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 13px;
    text-decoration: none;
    transition: var(--ruts-transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.ruts-km-btn-download:hover {
    background: var(--ruts-gold);
    color: var(--ruts-navy);
}

/* 4. Frontend Submission Form Styling */
.ruts-km-form-card {
    background: #FFFFFF;
    border: 1px solid var(--ruts-border);
    border-radius: var(--ruts-radius);
    padding: 30px;
    box-shadow: var(--ruts-shadow);
    max-width: 900px;
    margin: 30px auto;
}

/* Auth Required Locked Card */
.auth-required-card {
    text-align: center;
    padding: 50px 30px;
    border: 2px dashed #CBD5E1;
}

.ruts-auth-lock-icon {
    font-size: 54px;
    color: var(--ruts-navy);
    margin-bottom: 15px;
}

.auth-required-card h3 {
    color: var(--ruts-navy);
    font-size: 22px;
    margin: 0 0 10px 0;
}

.auth-required-card p {
    color: var(--ruts-text-muted);
    font-size: 15px;
    margin-bottom: 25px;
}

.ruts-btn-login {
    background: var(--ruts-navy);
    color: #FFFFFF;
    border: none;
    padding: 12px 30px;
    border-radius: 30px;
    font-size: 16px;
    font-weight: 700;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 15px rgba(13, 60, 117, 0.25);
    transition: var(--ruts-transition);
}

.ruts-btn-login:hover {
    background: var(--ruts-navy-dark);
    color: var(--ruts-gold);
    transform: translateY(-2px);
}

.ruts-km-form-header {
    border-bottom: 2px solid var(--ruts-yellow-warm);
    padding-bottom: 15px;
    margin-bottom: 25px;
}

.ruts-km-form-header h3 {
    color: var(--ruts-navy);
    font-size: 22px;
    margin: 0 0 6px 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.ruts-km-form-header p {
    color: var(--ruts-text-muted);
    font-size: 14px;
    margin: 0;
}

.ruts-km-alert {
    padding: 14px 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-size: 14.5px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.ruts-km-alert.success {
    background: #D1E7DD;
    color: #0F5132;
    border: 1px solid #BADBCC;
}

.ruts-km-alert.error {
    background: #F8D7DA;
    color: #842029;
    border: 1px solid #F5C2C7;
}

.ruts-form-row {
    display: flex;
    gap: 20px;
    margin-bottom: 18px;
}

.ruts-form-group {
    display: flex;
    flex-direction: column;
    margin-bottom: 18px;
    flex-grow: 1;
}

.ruts-form-group.col-6 { width: 50%; }
.ruts-form-group.col-4 { width: 33.33%; }
.ruts-form-group.col-8 { width: 66.66%; }

.ruts-form-group label {
    font-weight: 600;
    font-size: 14px;
    color: var(--ruts-navy);
    margin-bottom: 6px;
}

.ruts-form-group label .required {
    color: #DC2626;
}

.ruts-form-input,
.ruts-form-select,
.ruts-form-textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--ruts-border);
    border-radius: 8px;
    font-size: 14.5px;
    transition: var(--ruts-transition);
    outline: none;
    background: #FFFFFF;
}

.ruts-form-input:focus,
.ruts-form-select:focus,
.ruts-form-textarea:focus {
    border-color: var(--ruts-navy);
    box-shadow: 0 0 0 3px rgba(13, 60, 117, 0.12);
}

.ruts-form-file {
    padding: 8px;
    border: 1.5px dashed var(--ruts-border);
    border-radius: 8px;
    background: #F8FAFC;
}

.ruts-form-hint {
    font-size: 12px;
    color: var(--ruts-text-muted);
    margin-top: 4px;
}

.ruts-btn-submit {
    background: var(--ruts-navy);
    color: #FFFFFF;
    border: none;
    padding: 12px 28px;
    border-radius: 30px;
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    transition: var(--ruts-transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    box-shadow: 0 4px 15px rgba(13, 60, 117, 0.2);
    width: 100%;
    margin-top: 10px;
}

.ruts-btn-submit:hover {
    background: var(--ruts-navy-dark);
    box-shadow: 0 6px 20px rgba(13, 60, 117, 0.35);
    transform: translateY(-2px);
}

/* Responsive Form */
@media (max-width: 768px) {
    .ruts-form-row { flex-direction: column; gap: 0; }
    .ruts-form-group.col-6,
    .ruts-form-group.col-4,
    .ruts-form-group.col-8 { width: 100%; }
}