/* ============================================================
 * 共享表单组件样式（components/forms.css）
 * 从各页面内联样式中提取的公共表单元素，统一视觉与交互。
 * 依赖 base.css，被登录/管理/题库等页面复用。
 * ============================================================ */

/* ---------- 表单组 ---------- */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label,
.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #333;
    font-size: 0.9rem;
}

/* ---------- 输入框 ---------- */
.form-control,
.form-group input[type="text"],
.form-group input[type="password"],
.form-group input[type="email"],
.form-group input[type="number"],
.form-group input[type="url"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s, box-shadow 0.3s, background 0.2s;
    box-sizing: border-box;
    background: #fff;
    color: #2d3748;
}

.form-control:focus,
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--accent-color, #0ea5e9);
    box-shadow: 0 0 0 3px var(--accent-shadow, rgba(14, 165, 233, 0.1));
    outline: none;
    background: #fff;
}

/* 校验失败状态（validators.js 动态添加 .is-invalid） */
.form-control.is-invalid,
.form-group input.is-invalid {
    border-color: #dc3545;
    background: #fef5f5;
}

.form-control.is-valid,
.form-group input.is-valid {
    border-color: #28a745;
}

/* ---------- 校验错误文本 ---------- */
.invalid-feedback {
    color: #dc3545;
    font-size: 0.85rem;
    margin-top: 0.4rem;
    display: block;
    padding: 0.4rem 0.6rem;
    background: rgba(220, 53, 69, 0.08);
    border-radius: 6px;
    border-left: 3px solid #dc3545;
    animation: formFadeIn 0.25s ease;
}

/* ---------- 按钮 ---------- */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, opacity 0.2s;
    text-align: center;
    text-decoration: none;
}

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

.btn:active {
    transform: translateY(0);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-sm {
    padding: 0.4rem 0.9rem;
    font-size: 0.85rem;
}

.btn-primary {
    background: var(--accent-color, #0ea5e9);
    color: #fff;
}

.btn-primary:hover {
    box-shadow: 0 4px 12px var(--accent-shadow, rgba(14, 165, 233, 0.3));
}

.btn-success {
    background: #28a745;
    color: #fff;
}

.btn-success:hover {
    box-shadow: 0 4px 12px rgba(40, 167, 69, 0.3);
}

.btn-danger {
    background: #dc3545;
    color: #fff;
}

.btn-danger:hover {
    box-shadow: 0 4px 12px rgba(220, 53, 69, 0.3);
}

.btn-secondary {
    background: #6c757d;
    color: #fff;
}

/* ---------- 提示框 ---------- */
.alert {
    padding: 0.75rem 1rem;
    border-radius: 8px;
    margin-bottom: 1.25rem;
    font-size: 0.9rem;
}

.alert-danger {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-warning {
    background: #fff3cd;
    color: #856404;
    border: 1px solid #ffeeba;
}

.alert-info {
    background: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* ---------- 模态框 ---------- */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(2px);
}

.modal-content {
    background: #fff;
    margin: 5vh auto;
    padding: 0;
    border-radius: 16px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
    animation: modalSlideIn 0.3s ease;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid #e2e8f0;
}

.modal-header h3 {
    margin: 0;
    font-size: 1.25rem;
    color: #2d3748;
}

.modal-header .close {
    font-size: 1.75rem;
    font-weight: 300;
    cursor: pointer;
    color: #718096;
    line-height: 1;
}

.modal-header .close:hover {
    color: #2d3748;
}

.modal-body {
    padding: 1.5rem;
}

/* ---------- 动画 ---------- */
@keyframes formFadeIn {
    from { opacity: 0; transform: translateY(-4px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes modalSlideIn {
    from { opacity: 0; transform: translateY(-30px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
    .form-control,
    .form-group input,
    .form-group select,
    .form-group textarea {
        padding: 0.7rem 0.875rem;
        font-size: 0.95rem;
    }

    .btn {
        width: 100%;
        margin-bottom: 0.5rem;
        padding: 0.85rem 1rem;
    }

    .btn-sm {
        width: auto;
        margin-bottom: 0;
    }

    .modal-content {
        margin: 2vh auto;
        width: 95%;
    }
}