/* ==========================================================
   Source: student-registration.php | style block 1
   ========================================================== */

/* ===== CSS VARIABLES ===== */
        :root {
            --bg-body: #f4f6fa;
            --bg-main: #ffffff;
            --bg-card: #ffffff;
            --bg-card-hover: #f8fafc;
            --bg-input: #f1f5f9;
            --text-primary: #1e293b;
            --text-secondary: #475569;
            --text-muted: #64748b;
            --border-color: #edf2f7;
            --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.04);
            --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.06);
            --icon-wrap-bg: #eff6ff;
            --icon-wrap-color: #3b82f6;
            --toggle-bg: #e9edf4;
            --toggle-color: #1e293b;
            --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
            --scrollbar-track: #e9edf4;
            --scrollbar-thumb: #b0c4de;
            --scrollbar-thumb-hover: #8aa9d1;
            --gradient-brand: linear-gradient(135deg, #3b82f6, #8b5cf6);
            --gradient-header: linear-gradient(135deg, #1e3a6f, #2a4a8a);
            --avatar-bg: linear-gradient(135deg, #3b82f6, #8b5cf6);
            --header-btn-bg: #ffffff;
            --header-btn-border: #e9edf4;
            --header-btn-hover: #f1f5f9;
            --notif-bg: #ffffff;
            --notif-border: #edf2f7;
            --notif-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
            --notif-hover: #f8fafc;
            --notif-text: #1e293b;
            --notif-time: #94a3b8;
            --notif-unread-bg: #eff6ff;
            --notif-unread-border: #bfdbfe;
            --input-border: #e2e8f0;
            --input-focus: #3b82f6;
            --form-label: #1e293b;
            --form-helper: #64748b;
            --success-bg: #dcfce7;
            --success-color: #16a34a;
            --toggle-icon-color: #f59e0b;
            --theme-btn-bg: #ffffff;
            --theme-btn-border: #e9edf4;
            --theme-btn-hover: #f1f5f9;
            --theme-btn-color: #f59e0b;
            --error-color: #dc2626;
            --error-bg: #fee2e2;
            --file-preview-bg: #f8fafc;
            --file-preview-border: #e2e8f0;
            --file-preview-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
        }

        /* ===== DARK THEME ===== */
        [data-theme="dark"] {
            --bg-body: #0f172a;
            --bg-main: #1e293b;
            --bg-card: #1e293b;
            --bg-card-hover: #2d3a4f;
            --bg-input: #2d3a4f;
            --text-primary: #e2e8f0;
            --text-secondary: #94a3b8;
            --text-muted: #64748b;
            --border-color: #2d3a4f;
            --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.2);
            --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.3);
            --icon-wrap-bg: #1e2d47;
            --icon-wrap-color: #60a5fa;
            --toggle-bg: #2d3a4f;
            --toggle-color: #e2e8f0;
            --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
            --scrollbar-track: #1e293b;
            --scrollbar-thumb: #3d4a5f;
            --scrollbar-thumb-hover: #4a5a6f;
            --gradient-brand: linear-gradient(135deg, #3b82f6, #8b5cf6);
            --gradient-header: linear-gradient(135deg, #0f172a, #1e293b);
            --avatar-bg: linear-gradient(135deg, #3b82f6, #8b5cf6);
            --header-btn-bg: #1e293b;
            --header-btn-border: #2d3a4f;
            --header-btn-hover: #2d3a4f;
            --notif-bg: #1e293b;
            --notif-border: #2d3a4f;
            --notif-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
            --notif-hover: #2d3a4f;
            --notif-text: #e2e8f0;
            --notif-time: #94a3b8;
            --notif-unread-bg: #1a2a4a;
            --notif-unread-border: #3b82f6;
            --input-border: #3d4a5f;
            --input-focus: #3b82f6;
            --form-label: #e2e8f0;
            --form-helper: #94a3b8;
            --success-bg: #1a3a2a;
            --success-color: #4ade80;
            --toggle-icon-color: #fbbf24;
            --theme-btn-bg: #1e293b;
            --theme-btn-border: #2d3a4f;
            --theme-btn-hover: #2d3a4f;
            --theme-btn-color: #fbbf24;
            --error-color: #f87171;
            --error-bg: #3a1a1a;
            --file-preview-bg: #1e293b;
            --file-preview-border: #2d3a4f;
            --file-preview-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
        }

        /* ===== RESET & BASE ===== */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', sans-serif;
            background: var(--bg-body);
            color: var(--text-primary);
            display: flex;
            flex-direction: column;
            min-height: 100vh;
            transition: background 0.3s ease, color 0.3s ease;
            margin: 0;
            margin-top: 50px;
            padding: 0;
        }

        ::-webkit-scrollbar {
            width: 5px;
            height: 5px;
        }
        ::-webkit-scrollbar-track {
            background: var(--scrollbar-track);
            border-radius: 10px;
        }
        ::-webkit-scrollbar-thumb {
            background: var(--scrollbar-thumb);
            border-radius: 10px;
        }
        ::-webkit-scrollbar-thumb:hover {
            background: var(--scrollbar-thumb-hover);
        }

        /* ===== MAIN CONTENT ===== */
        .main {
            flex: 1;
            max-width: 1100px;
            width: 100%;
            padding: 28px 32px 40px;
            background: var(--bg-body);
            transition: background 0.3s ease;
            margin: 0 auto;
        }

        /* ===== PAGE HEADER (centered) ===== */
        .page-header {
            text-align: center;
            margin-bottom: 28px;
        }
        .page-header h1 {
            font-size: 28px;
            font-weight: 700;
            color: var(--text-primary);
            letter-spacing: -0.5px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 12px;
        }
        .page-header h1 i {
            color: #3b82f6;
            background: var(--icon-wrap-bg);
            padding: 10px;
            border-radius: 50%;
            font-size: 24px;
        }
        .page-header .sub-heading {
            font-size: 15px;
            color: var(--text-muted);
            margin-top: 6px;
        }

        /* ===== FORM CARD (ENHANCED) ===== */
        .form-card {
            background: var(--bg-card);
            border-radius: 20px;
            border: 1px solid var(--border-color);
            box-shadow: 0 8px 40px rgba(0, 0, 0, 0.06);
            padding: 36px 40px;
            transition: background 0.3s ease, border-color 0.3s ease;
            max-width: 960px;
            margin: 0 auto;
            margin-top: 50px;
            position: relative;
            overflow: hidden;
        }
        /* ===== BOLD GRADIENT TOP BORDER ===== */
        .form-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 6px;
            background: var(--gradient-brand);
            border-radius: 20px 20px 0 0;
            z-index: 1;
        }
        /* Subtle inner shadow for depth */
        .form-card::after {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            border-radius: 20px;
            box-shadow: inset 0 0 0 1px rgba(255,255,255,0.05);
            pointer-events: none;
        }

        .form-card .form-section {
            margin-bottom: 40px;
        }
        .form-card .form-section:last-child {
            margin-bottom: 0;
        }

        .form-card .form-section .section-title {
            font-size: 17px;
            font-weight: 600;
            color: var(--text-primary);
            margin-bottom: 6px;
            display: flex;
            align-items: center;
            gap: 12px;
        }
        .form-card .form-section .section-title i {
            color: #3b82f6;
            font-size: 20px;
            width: 28px;
            text-align: center;
        }
        .form-card .form-section .section-desc {
            font-size: 13px;
            color: var(--text-muted);
            margin-bottom: 18px;
            padding-left: 40px;
        }
        .form-card .form-divider {
            height: 1px;
            background: var(--border-color);
            margin: 28px 0;
        }

        /* ---- Form Grid ---- */
        .form-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 18px 24px;
        }
        .form-grid .full-width {
            grid-column: 1 / -1;
        }

        .form-group {
            display: flex;
            flex-direction: column;
            gap: 5px;
        }
        .form-group label {
            font-size: 13px;
            font-weight: 500;
            color: var(--form-label);
            display: flex;
            align-items: center;
            gap: 4px;
        }
        .form-group label .required {
            color: #dc2626;
            font-weight: 700;
        }
        .form-group .helper {
            font-size: 12px;
            color: var(--form-helper);
            margin-top: 2px;
        }
        .form-group input,
        .form-group select,
        .form-group textarea {
            padding: 10px 14px;
            border-radius: 10px;
            border: 1px solid var(--input-border);
            background: var(--bg-input);
            color: var(--text-primary);
            font-size: 14px;
            font-family: 'Inter', sans-serif;
            transition: all 0.3s ease;
            width: 100%;
            outline: none;
        }
        .form-group input:focus,
        .form-group select:focus,
        .form-group textarea:focus {
            border-color: var(--input-focus);
            box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.12);
        }
        .form-group input::placeholder,
        .form-group textarea::placeholder {
            color: var(--text-muted);
        }
        .form-group textarea {
            resize: vertical;
            min-height: 80px;
        }
        .form-group select {
            appearance: none;
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
            background-repeat: no-repeat;
            background-position: right 12px center;
            padding-right: 34px;
            cursor: pointer;
        }
        .form-group select option {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        /* ---- Password ---- */
        .password-wrapper {
            position: relative;
        }
        .password-wrapper input {
            padding-right: 44px;
        }
        .password-wrapper .toggle-password {
            position: absolute;
            right: 12px;
            top: 50%;
            transform: translateY(-50%);
            background: none;
            border: none;
            color: var(--text-muted);
            cursor: pointer;
            font-size: 16px;
            padding: 4px;
            transition: color 0.2s;
        }
        .password-wrapper .toggle-password:hover {
            color: var(--text-primary);
        }
        .password-match-info {
            font-size: 12px;
            margin-top: 4px;
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .password-match-info .match-icon {
            font-size: 14px;
        }
        .password-match-info.match {
            color: var(--success-color);
        }
        .password-match-info.no-match {
            color: var(--error-color);
        }
        .password-match-info .helper-text {
            color: var(--text-muted);
        }

        /* ---- File Upload ---- */
        .file-upload-wrapper {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .file-drop-zone {
            border: 2px dashed var(--input-border);
            border-radius: 12px;
            padding: 24px 20px;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s ease;
            background: var(--bg-input);
            position: relative;
        }
        .file-drop-zone:hover {
            border-color: var(--input-focus);
            background: var(--bg-card-hover);
        }
        .file-drop-zone.dragover {
            border-color: var(--input-focus);
            background: var(--icon-wrap-bg);
            transform: scale(1.01);
        }
        .file-drop-zone .drop-icon {
            font-size: 36px;
            color: var(--text-muted);
            margin-bottom: 8px;
            display: block;
        }
        .file-drop-zone .drop-text {
            font-size: 14px;
            color: var(--text-secondary);
            font-weight: 500;
        }
        .file-drop-zone .drop-sub {
            font-size: 12px;
            color: var(--text-muted);
            margin-top: 4px;
        }
        .file-drop-zone input[type="file"] {
            position: absolute;
            inset: 0;
            opacity: 0;
            cursor: pointer;
        }
        .file-preview-container {
            display: none;
            flex-wrap: wrap;
            gap: 12px;
            margin-top: 4px;
        }
        .file-preview-container.has-files {
            display: flex;
        }
        .file-preview-item {
            display: flex;
            align-items: center;
            gap: 12px;
            background: var(--file-preview-bg);
            border: 1px solid var(--file-preview-border);
            border-radius: 10px;
            padding: 10px 14px;
            box-shadow: var(--file-preview-shadow);
            transition: all 0.2s ease;
            position: relative;
            min-width: 160px;
            flex: 0 1 auto;
        }
        .file-preview-item:hover {
            box-shadow: var(--shadow-card-hover);
        }
        .file-preview-item .file-thumb {
            width: 44px;
            height: 44px;
            border-radius: 8px;
            background: var(--icon-wrap-bg);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 22px;
            color: var(--icon-wrap-color);
            flex-shrink: 0;
            overflow: hidden;
        }
        .file-preview-item .file-thumb img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }
        .file-preview-item .file-info {
            flex: 1;
            min-width: 0;
        }
        .file-preview-item .file-info .file-name {
            font-size: 13px;
            font-weight: 500;
            color: var(--text-primary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            max-width: 120px;
        }
        .file-preview-item .file-info .file-size {
            font-size: 11px;
            color: var(--text-muted);
        }
        .file-preview-item .file-remove {
            background: none;
            border: none;
            color: var(--text-muted);
            cursor: pointer;
            padding: 4px 6px;
            border-radius: 6px;
            transition: all 0.2s ease;
            font-size: 14px;
            flex-shrink: 0;
        }
        .file-preview-item .file-remove:hover {
            color: #dc2626;
            background: var(--error-bg);
        }

        /* ---- Form Actions ---- */
        .form-actions {
            display: flex;
            align-items: center;
            gap: 14px;
            padding-top: 24px;
            border-top: 1px solid var(--border-color);
            margin-top: 8px;
            flex-wrap: wrap;
        }
        .form-actions .btn-submit {
            padding: 12px 36px;
            border-radius: 10px;
            border: none;
            background: var(--gradient-brand);
            color: #fff;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            font-family: 'Inter', sans-serif;
            display: inline-flex;
            align-items: center;
            gap: 10px;
        }
        .form-actions .btn-submit:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(59, 130, 246, 0.3);
        }
        .form-actions .btn-submit:active {
            transform: translateY(0);
        }
        .form-actions .btn-secondary {
            padding: 12px 28px;
            border-radius: 10px;
            border: 1px solid var(--border-color);
            background: transparent;
            color: var(--text-secondary);
            font-size: 14px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.2s ease;
            font-family: 'Inter', sans-serif;
        }
        .form-actions .btn-secondary:hover {
            background: var(--bg-input);
            color: var(--text-primary);
        }

        /* ---- Messages ---- */
        .success-message {
            display: none;
            padding: 16px 20px;
            border-radius: 12px;
            background: var(--success-bg);
            color: var(--success-color);
            border: 1px solid var(--success-color);
            margin-bottom: 20px;
            align-items: center;
            gap: 12px;
            font-weight: 500;
            max-width: 960px;
            margin-left: auto;
            margin-right: auto;
        }
        .success-message.show {
            display: flex;
        }
        .success-message i {
            font-size: 20px;
        }
        .error-message {
            padding: 16px 20px;
            border-radius: 12px;
            background: var(--error-bg);
            color: var(--error-color);
            border: 1px solid var(--error-color);
            margin-bottom: 20px;
            display: flex;
            align-items: center;
            gap: 12px;
            font-weight: 500;
            max-width: 960px;
            margin-left: auto;
            margin-right: auto;
        }
        .error-message i {
            font-size: 20px;
        }

        /* ---- Responsive ---- */
        @media (max-width: 992px) {
            .main {
                padding: 20px 20px 30px;
            }
            .form-card {
                padding: 24px 20px;
            }
            .form-grid {
                grid-template-columns: 1fr;
            }
            .form-grid .full-width {
                grid-column: 1;
            }
        }

        @media (max-width: 600px) {
            .main {
                padding: 16px 12px 24px;
            }
            .page-header h1 {
                font-size: 22px;
            }
            .page-header h1 i {
                font-size: 18px;
                padding: 8px;
            }
            .form-card {
                padding: 18px 14px;
            }
            .form-card .form-section .section-desc {
                padding-left: 0;
            }
            .form-actions {
                flex-direction: column;
                align-items: stretch;
            }
            .form-actions .btn-submit,
            .form-actions .btn-secondary {
                justify-content: center;
                width: 100%;
            }
            .file-preview-item {
                flex: 1 1 100%;
                min-width: 0;
            }
            .file-preview-item .file-info .file-name {
                max-width: 100px;
            }
        }

        /* ===== TRANSITIONS ===== */
        * {
            transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease, opacity 0.3s ease;
        }

        [data-theme="dark"] .form-group select {
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2394a3b8' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
        }

        #studentId {
            background: var(--bg-input);
            opacity: 0.7;
            cursor: not-allowed;
        }
        #studentId:focus {
            border-color: var(--input-border);
            box-shadow: none;
        }